mpv/filters/f_decoder_wrapper.c

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/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <float.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <math.h>
#include <assert.h>
#include <libavutil/buffer.h>
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
#include <libavutil/common.h>
#include <libavutil/rational.h>
#include "options/options.h"
#include "common/msg.h"
#include "options/m_config.h"
#include "osdep/timer.h"
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
#include "osdep/threads.h"
#include "demux/demux.h"
#include "demux/packet.h"
#include "common/codecs.h"
#include "common/global.h"
#include "common/recorder.h"
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
#include "misc/dispatch.h"
#include "audio/aframe.h"
#include "video/out/vo.h"
#include "video/csputils.h"
#include "demux/stheader.h"
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
#include "f_async_queue.h"
#include "f_decoder_wrapper.h"
#include "f_demux_in.h"
#include "filter_internal.h"
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct dec_queue_opts {
bool use_queue;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
int64_t max_bytes;
int64_t max_samples;
double max_duration;
};
#define OPT_BASE_STRUCT struct dec_queue_opts
static const struct m_option dec_queue_opts_list[] = {
{"enable", OPT_BOOL(use_queue)},
{"max-secs", OPT_DOUBLE(max_duration), M_RANGE(0, DBL_MAX)},
{"max-bytes", OPT_BYTE_SIZE(max_bytes), M_RANGE(0, M_MAX_MEM_BYTES)},
{"max-samples", OPT_INT64(max_samples), M_RANGE(0, DBL_MAX)},
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
{0}
};
static const struct m_sub_options vdec_queue_conf = {
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
.opts = dec_queue_opts_list,
.size = sizeof(struct dec_queue_opts),
.defaults = &(const struct dec_queue_opts){
.max_bytes = 512 * 1024 * 1024,
.max_samples = 50,
.max_duration = 2,
},
};
static const struct m_sub_options adec_queue_conf = {
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
.opts = dec_queue_opts_list,
.size = sizeof(struct dec_queue_opts),
.defaults = &(const struct dec_queue_opts){
.max_bytes = 1 * 1024 * 1024,
.max_samples = 48000,
.max_duration = 1,
},
};
#undef OPT_BASE_STRUCT
#define OPT_BASE_STRUCT struct dec_wrapper_opts
struct dec_wrapper_opts {
double movie_aspect;
int aspect_method;
double fps_override;
bool correct_pts;
int video_rotate;
char *audio_decoders;
char *video_decoders;
char *audio_spdif;
struct dec_queue_opts *vdec_queue_opts;
struct dec_queue_opts *adec_queue_opts;
int64_t video_reverse_size;
int64_t audio_reverse_size;
};
options: Make validation and help possible for all option types Today, validation is only possible for string type options. But there's no particular reason why it needs to be restricted in this way, and there are potential uses, to allow other options to be validated without forcing the option to have to reimplement parsing from scratch. The first part, simply making the validation function an explicit field instead of overloading priv is simple enough. But if we only do that, then the validation function still needs to deal with the raw pre-parsed string. Instead, we want to allow the value to be parsed before it is validated. That in turn leads to us having validator functions that should be type aware. Unfortunately, that means we need to keep the explicit macro like OPT_STRING_VALIDATE() as a way to enforce the correct typing of the function. Otherwise, we'd have to have the validator take a void * and hope the implementation can cast it correctly. For help, we don't have this problem, as help doesn't look at the value. Then, we turn validators that are really help generators into explicit help functions and where a validator is help + validation, we split them into two parts. I have, however, left functions that need to query information for both help and validation as single functions to avoid code duplication. In this change, I have not added an other OPT_FOO_VALIDATE() macros as they are not needed, but I will add some in a separate change to illustrate the pattern.
2021-02-21 00:41:44 +00:00
static int decoder_list_help(struct mp_log *log, const m_option_t *opt,
struct bstr name);
const struct m_sub_options dec_wrapper_conf = {
.opts = (const struct m_option[]){
{"correct-pts", OPT_BOOL(correct_pts)},
{"container-fps-override", OPT_DOUBLE(fps_override), M_RANGE(0, DBL_MAX)},
options: Make validation and help possible for all option types Today, validation is only possible for string type options. But there's no particular reason why it needs to be restricted in this way, and there are potential uses, to allow other options to be validated without forcing the option to have to reimplement parsing from scratch. The first part, simply making the validation function an explicit field instead of overloading priv is simple enough. But if we only do that, then the validation function still needs to deal with the raw pre-parsed string. Instead, we want to allow the value to be parsed before it is validated. That in turn leads to us having validator functions that should be type aware. Unfortunately, that means we need to keep the explicit macro like OPT_STRING_VALIDATE() as a way to enforce the correct typing of the function. Otherwise, we'd have to have the validator take a void * and hope the implementation can cast it correctly. For help, we don't have this problem, as help doesn't look at the value. Then, we turn validators that are really help generators into explicit help functions and where a validator is help + validation, we split them into two parts. I have, however, left functions that need to query information for both help and validation as single functions to avoid code duplication. In this change, I have not added an other OPT_FOO_VALIDATE() macros as they are not needed, but I will add some in a separate change to illustrate the pattern.
2021-02-21 00:41:44 +00:00
{"ad", OPT_STRING(audio_decoders),
.help = decoder_list_help},
{"vd", OPT_STRING(video_decoders),
.help = decoder_list_help},
{"audio-spdif", OPT_STRING(audio_spdif),
.help = decoder_list_help},
{"video-rotate", OPT_CHOICE(video_rotate, {"no", -1}),
.flags = UPDATE_IMGPAR, M_RANGE(0, 359)},
{"video-aspect-override", OPT_ASPECT(movie_aspect),
.flags = UPDATE_IMGPAR, M_RANGE(-1, 10)},
{"video-aspect-method", OPT_CHOICE(aspect_method,
{"bitstream", 1}, {"container", 2}),
.flags = UPDATE_IMGPAR},
{"vd-queue", OPT_SUBSTRUCT(vdec_queue_opts, vdec_queue_conf)},
{"ad-queue", OPT_SUBSTRUCT(adec_queue_opts, adec_queue_conf)},
{"video-reversal-buffer", OPT_BYTE_SIZE(video_reverse_size),
M_RANGE(0, M_MAX_MEM_BYTES)},
{"audio-reversal-buffer", OPT_BYTE_SIZE(audio_reverse_size),
M_RANGE(0, M_MAX_MEM_BYTES)},
{"fps", OPT_REPLACED("container-fps-override")},
{0}
},
.size = sizeof(struct dec_wrapper_opts),
.defaults = &(const struct dec_wrapper_opts){
.correct_pts = true,
.movie_aspect = -1.,
.aspect_method = 2,
.video_reverse_size = 1 * 1024 * 1024 * 1024,
.audio_reverse_size = 64 * 1024 * 1024,
},
};
struct priv {
struct mp_log *log;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct sh_stream *header;
// --- The following fields are to be accessed by dec_dispatch (or if that
// field is NULL, by the mp_decoder_wrapper user thread).
// Use thread_lock() for access outside of the decoder thread.
bool request_terminate_dec_thread;
struct mp_filter *dec_root_filter; // thread root filter; no thread => NULL
struct mp_filter *decf; // wrapper filter which drives the decoder
struct m_config_cache *opt_cache;
struct dec_wrapper_opts *opts;
struct dec_queue_opts *queue_opts;
struct mp_stream_info stream_info;
struct mp_codec_params *codec;
struct mp_decoder *decoder;
// Demuxer output.
struct mp_pin *demux;
// Last PTS from decoder (set with each vd_driver->decode() call)
double codec_pts;
int num_codec_pts_problems;
// Last packet DTS from decoder (passed through from source packets)
double codec_dts;
int num_codec_dts_problems;
// PTS or DTS of packet first read
double first_packet_pdts;
// There was at least one packet with nonsense timestamps.
// Intentionally not reset on seeks; its whole purpose is to enable faster
// future seeks.
int has_broken_packet_pts; // <0: uninitialized, 0: no problems, 1: broken
int has_broken_decoded_pts;
int packets_without_output; // number packets sent without frame received
// Final PTS of previously decoded frame
double pts;
struct mp_image_params dec_format, last_format, fixed_format;
double fps;
double start_pts;
double start, end;
struct demux_packet *new_segment;
struct mp_frame packet;
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
bool packet_fed, preroll_discard;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
size_t reverse_queue_byte_size;
struct mp_frame *reverse_queue;
int num_reverse_queue;
bool reverse_queue_complete;
struct mp_frame decoded_coverart;
int coverart_returned; // 0: no, 1: coverart frame itself, 2: EOF returned
int play_dir;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
// --- The following fields can be accessed only from the mp_decoder_wrapper
// user thread.
struct mp_decoder_wrapper public;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
// --- Specific access depending on threading stuff.
struct mp_async_queue *queue; // decoded frame output queue
struct mp_dispatch_queue *dec_dispatch; // non-NULL if decoding thread used
bool dec_thread_lock; // debugging (esp. for no-thread case)
2023-10-21 02:55:41 +00:00
mp_thread dec_thread;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
bool dec_thread_valid;
2023-10-21 02:55:41 +00:00
mp_mutex cache_lock;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
// --- Protected by cache_lock.
char *cur_hwdec;
char *decoder_desc;
bool try_spdif;
bool attached_picture;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
bool pts_reset;
int attempt_framedrops; // try dropping this many frames
int dropped_frames; // total frames _probably_ dropped
};
options: Make validation and help possible for all option types Today, validation is only possible for string type options. But there's no particular reason why it needs to be restricted in this way, and there are potential uses, to allow other options to be validated without forcing the option to have to reimplement parsing from scratch. The first part, simply making the validation function an explicit field instead of overloading priv is simple enough. But if we only do that, then the validation function still needs to deal with the raw pre-parsed string. Instead, we want to allow the value to be parsed before it is validated. That in turn leads to us having validator functions that should be type aware. Unfortunately, that means we need to keep the explicit macro like OPT_STRING_VALIDATE() as a way to enforce the correct typing of the function. Otherwise, we'd have to have the validator take a void * and hope the implementation can cast it correctly. For help, we don't have this problem, as help doesn't look at the value. Then, we turn validators that are really help generators into explicit help functions and where a validator is help + validation, we split them into two parts. I have, however, left functions that need to query information for both help and validation as single functions to avoid code duplication. In this change, I have not added an other OPT_FOO_VALIDATE() macros as they are not needed, but I will add some in a separate change to illustrate the pattern.
2021-02-21 00:41:44 +00:00
static int decoder_list_help(struct mp_log *log, const m_option_t *opt,
struct bstr name)
{
if (strcmp(opt->name, "ad") == 0) {
struct mp_decoder_list *list = audio_decoder_list();
mp_print_decoders(log, MSGL_INFO, "Audio decoders:", list);
talloc_free(list);
return M_OPT_EXIT;
}
if (strcmp(opt->name, "vd") == 0) {
struct mp_decoder_list *list = video_decoder_list();
mp_print_decoders(log, MSGL_INFO, "Video decoders:", list);
talloc_free(list);
return M_OPT_EXIT;
}
if (strcmp(opt->name, "audio-spdif") == 0) {
mp_info(log, "Choices: ac3,dts-hd,dts (and possibly more)\n");
return M_OPT_EXIT;
}
return 1;
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
// Update cached values for main thread which require access to the decoder
// thread state. Must run on/locked with decoder thread.
static void update_cached_values(struct priv *p)
{
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->cur_hwdec = NULL;
if (p->decoder && p->decoder->control)
p->decoder->control(p->decoder->f, VDCTRL_GET_HWDEC, &p->cur_hwdec);
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
// Lock the decoder thread. This may synchronously wait until the decoder thread
// is done with its current work item (such as waiting for a frame), and thus
// may block for a while. (I.e. avoid during normal playback.)
// If no decoder thread is running, this is a no-op, except for some debug stuff.
static void thread_lock(struct priv *p)
{
if (p->dec_dispatch)
mp_dispatch_lock(p->dec_dispatch);
assert(!p->dec_thread_lock);
p->dec_thread_lock = true;
}
// Undo thread_lock().
static void thread_unlock(struct priv *p)
{
assert(p->dec_thread_lock);
p->dec_thread_lock = false;
if (p->dec_dispatch)
mp_dispatch_unlock(p->dec_dispatch);
}
// This resets only the decoder. Unlike a full reset(), this doesn't imply a
// seek reset. This distinction exists only when using timeline stuff (EDL and
// ordered chapters). timeline stuff needs to reset the decoder state, but keep
// some of the user-relevant state.
static void reset_decoder(struct priv *p)
{
p->first_packet_pdts = MP_NOPTS_VALUE;
p->start_pts = MP_NOPTS_VALUE;
p->codec_pts = MP_NOPTS_VALUE;
p->codec_dts = MP_NOPTS_VALUE;
p->num_codec_pts_problems = 0;
p->num_codec_dts_problems = 0;
p->has_broken_decoded_pts = 0;
p->packets_without_output = 0;
mp_frame_unref(&p->packet);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
p->packet_fed = false;
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
p->preroll_discard = false;
talloc_free(p->new_segment);
p->new_segment = NULL;
p->start = p->end = MP_NOPTS_VALUE;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
if (p->decoder)
mp_filter_reset(p->decoder->f);
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
static void decf_reset(struct mp_filter *f)
{
struct priv *p = f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
assert(p->decf == f);
p->pts = MP_NOPTS_VALUE;
p->last_format = p->fixed_format = (struct mp_image_params){0};
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
p->pts_reset = false;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->attempt_framedrops = 0;
p->dropped_frames = 0;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
p->coverart_returned = 0;
for (int n = 0; n < p->num_reverse_queue; n++)
mp_frame_unref(&p->reverse_queue[n]);
p->num_reverse_queue = 0;
p->reverse_queue_byte_size = 0;
p->reverse_queue_complete = false;
reset_decoder(p);
}
int mp_decoder_wrapper_control(struct mp_decoder_wrapper *d,
enum dec_ctrl cmd, void *arg)
{
struct priv *p = d->f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
int res = CONTROL_UNKNOWN;
if (cmd == VDCTRL_GET_HWDEC) {
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
*(char **)arg = p->cur_hwdec;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
} else {
thread_lock(p);
if (p->decoder && p->decoder->control)
res = p->decoder->control(p->decoder->f, cmd, arg);
update_cached_values(p);
thread_unlock(p);
}
return res;
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
static void decf_destroy(struct mp_filter *f)
{
struct priv *p = f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
assert(p->decf == f);
if (p->decoder) {
MP_DBG(f, "Uninit decoder.\n");
talloc_free(p->decoder->f);
p->decoder = NULL;
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
decf_reset(f);
mp_frame_unref(&p->decoded_coverart);
}
struct mp_decoder_list *video_decoder_list(void)
{
struct mp_decoder_list *list = talloc_zero(NULL, struct mp_decoder_list);
vd_lavc.add_decoders(list);
return list;
}
struct mp_decoder_list *audio_decoder_list(void)
{
struct mp_decoder_list *list = talloc_zero(NULL, struct mp_decoder_list);
ad_lavc.add_decoders(list);
return list;
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
static bool reinit_decoder(struct priv *p)
{
if (p->decoder)
talloc_free(p->decoder->f);
p->decoder = NULL;
reset_decoder(p);
p->has_broken_packet_pts = -10; // needs 10 packets to reach decision
talloc_free(p->decoder_desc);
p->decoder_desc = NULL;
const struct mp_decoder_fns *driver = NULL;
struct mp_decoder_list *list = NULL;
char *user_list = NULL;
char *fallback = NULL;
if (p->codec->type == STREAM_VIDEO) {
driver = &vd_lavc;
user_list = p->opts->video_decoders;
fallback = "h264";
} else if (p->codec->type == STREAM_AUDIO) {
driver = &ad_lavc;
user_list = p->opts->audio_decoders;
fallback = "aac";
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
bool try_spdif = p->try_spdif;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
if (try_spdif && p->codec->codec) {
struct mp_decoder_list *spdif =
select_spdif_codec(p->codec->codec, p->opts->audio_spdif);
if (spdif->num_entries) {
driver = &ad_spdif;
list = spdif;
} else {
talloc_free(spdif);
}
}
}
2023-11-18 22:30:42 +00:00
if (!driver)
return false;
if (!list) {
struct mp_decoder_list *full = talloc_zero(NULL, struct mp_decoder_list);
2023-11-18 22:30:42 +00:00
driver->add_decoders(full);
const char *codec = p->codec->codec;
if (codec && strcmp(codec, "null") == 0)
codec = fallback;
list = mp_select_decoders(p->log, full, codec, user_list);
talloc_free(full);
}
mp_print_decoders(p->log, MSGL_V, "Codec list:", list);
for (int n = 0; n < list->num_entries; n++) {
struct mp_decoder_entry *sel = &list->entries[n];
MP_VERBOSE(p, "Opening decoder %s\n", sel->decoder);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->decoder = driver->create(p->decf, p->codec, sel->decoder);
if (p->decoder) {
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
const char *d = sel->desc && sel->desc[0] ? sel->desc : sel->decoder;
p->decoder_desc = talloc_strdup(p, d);
MP_VERBOSE(p, "Selected codec: %s\n", p->decoder_desc);
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
break;
}
MP_WARN(p, "Decoder init failed for %s\n", sel->decoder);
}
if (!p->decoder) {
MP_ERR(p, "Failed to initialize a decoder for codec '%s'.\n",
p->codec->codec ? p->codec->codec : "<?>");
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
update_cached_values(p);
talloc_free(list);
return !!p->decoder;
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
bool mp_decoder_wrapper_reinit(struct mp_decoder_wrapper *d)
{
struct priv *p = d->f->priv;
thread_lock(p);
bool res = reinit_decoder(p);
thread_unlock(p);
return res;
}
void mp_decoder_wrapper_get_desc(struct mp_decoder_wrapper *d,
char *buf, size_t buf_size)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
snprintf(buf, buf_size, "%s", p->decoder_desc ? p->decoder_desc : "");
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
}
void mp_decoder_wrapper_set_frame_drops(struct mp_decoder_wrapper *d, int num)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
p->attempt_framedrops = num;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
}
int mp_decoder_wrapper_get_frames_dropped(struct mp_decoder_wrapper *d)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
int res = p->dropped_frames;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
return res;
}
double mp_decoder_wrapper_get_container_fps(struct mp_decoder_wrapper *d)
{
struct priv *p = d->f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
thread_lock(p);
double res = p->fps;
thread_unlock(p);
return res;
}
void mp_decoder_wrapper_set_spdif_flag(struct mp_decoder_wrapper *d, bool spdif)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
p->try_spdif = spdif;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
}
void mp_decoder_wrapper_set_coverart_flag(struct mp_decoder_wrapper *d, bool c)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
p->attached_picture = c;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
}
bool mp_decoder_wrapper_get_pts_reset(struct mp_decoder_wrapper *d)
{
struct priv *p = d->f->priv;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
bool res = p->pts_reset;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
return res;
}
void mp_decoder_wrapper_set_play_dir(struct mp_decoder_wrapper *d, int dir)
{
struct priv *p = d->f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
thread_lock(p);
p->play_dir = dir;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
thread_unlock(p);
}
static void fix_image_params(struct priv *p,
struct mp_image_params *params)
{
struct mp_image_params m = *params;
struct mp_codec_params *c = p->codec;
struct dec_wrapper_opts *opts = p->opts;
MP_VERBOSE(p, "Decoder format: %s\n", mp_image_params_to_str(params));
p->dec_format = *params;
// While mp_image_params normally always have to have d_w/d_h set, the
// decoder signals unknown bitstream aspect ratio with both set to 0.
bool use_container = true;
if (opts->aspect_method == 1 && m.p_w > 0 && m.p_h > 0) {
MP_VERBOSE(p, "Using bitstream aspect ratio.\n");
use_container = false;
}
if (use_container && c->par_w > 0 && c->par_h) {
MP_VERBOSE(p, "Using container aspect ratio.\n");
m.p_w = c->par_w;
m.p_h = c->par_h;
}
if (opts->movie_aspect >= 0) {
MP_VERBOSE(p, "Forcing user-set aspect ratio.\n");
if (opts->movie_aspect == 0) {
m.p_w = m.p_h = 1;
} else {
AVRational a = av_d2q(opts->movie_aspect, INT_MAX);
mp_image_params_set_dsize(&m, a.num, a.den);
}
}
// Assume square pixels if no aspect ratio is set at all.
if (m.p_w <= 0 || m.p_h <= 0)
m.p_w = m.p_h = 1;
m.stereo3d = p->codec->stereo_mode;
2023-09-01 20:26:05 +00:00
if (!mp_rect_equals(&p->codec->crop, &(struct mp_rect){0})) {
struct mp_rect crop = p->codec->crop;
// Offset to respect existing decoder crop.
crop.x0 += m.crop.x0;
crop.x1 += m.crop.x0;
crop.y0 += m.crop.y0;
crop.y1 += m.crop.y0;
// Crop has to be inside existing image bounds.
if (mp_image_crop_valid(&(struct mp_image_params) {
.w = mp_rect_w(m.crop), .h = mp_rect_h(m.crop), .crop = crop }))
{
m.crop = crop;
} else {
MP_WARN(p, "Invalid container crop %dx%d+%d+%d for %dx%d image\n",
mp_rect_w(crop), mp_rect_h(crop), crop.x0, crop.y0,
mp_rect_w(m.crop), mp_rect_h(m.crop));
}
}
if (opts->video_rotate < 0) {
m.rotate = 0;
} else {
// ffmpeg commit 535a835e51 says that frame rotate takes priority
if (!m.rotate)
m.rotate = p->codec->rotate;
m.rotate = (m.rotate + opts->video_rotate) % 360;
}
mp_colorspace_merge(&m.color, &c->color);
// Guess missing colorspace fields from metadata. This guarantees all
// fields are at least set to legal values afterwards.
mp_image_params_guess_csp(&m);
p->last_format = *params;
p->fixed_format = m;
}
void mp_decoder_wrapper_reset_params(struct mp_decoder_wrapper *d)
{
struct priv *p = d->f->priv;
p->last_format = (struct mp_image_params){0};
}
void mp_decoder_wrapper_get_video_dec_params(struct mp_decoder_wrapper *d,
struct mp_image_params *m)
{
struct priv *p = d->f->priv;
*m = p->dec_format;
}
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
// This code exists only because multimedia is so god damn crazy. In a sane
// world, the video decoder would always output a video frame with a valid PTS;
// this deals with cases where it doesn't.
static void crazy_video_pts_stuff(struct priv *p, struct mp_image *mpi)
{
// Note: the PTS is reordered, but the DTS is not. Both must be monotonic.
if (mpi->pts != MP_NOPTS_VALUE) {
if (mpi->pts < p->codec_pts)
p->num_codec_pts_problems++;
p->codec_pts = mpi->pts;
}
if (mpi->dts != MP_NOPTS_VALUE) {
if (mpi->dts <= p->codec_dts)
p->num_codec_dts_problems++;
p->codec_dts = mpi->dts;
}
if (p->has_broken_packet_pts < 0)
p->has_broken_packet_pts++;
if (p->num_codec_pts_problems)
p->has_broken_packet_pts = 1;
// If PTS is unset, or non-monotonic, fall back to DTS.
if ((p->num_codec_pts_problems > p->num_codec_dts_problems ||
mpi->pts == MP_NOPTS_VALUE) && mpi->dts != MP_NOPTS_VALUE)
mpi->pts = mpi->dts;
// Compensate for incorrectly using mpeg-style DTS for avi timestamps.
if (p->decoder && p->decoder->control && p->codec->avi_dts &&
mpi->pts != MP_NOPTS_VALUE && p->fps > 0)
{
int delay = -1;
p->decoder->control(p->decoder->f, VDCTRL_GET_BFRAMES, &delay);
mpi->pts -= MPMAX(delay, 0) / p->fps;
}
}
// Return true if the current frame is outside segment range.
static bool process_decoded_frame(struct priv *p, struct mp_frame *frame)
{
if (frame->type == MP_FRAME_EOF) {
// if we were just draining current segment, don't propagate EOF
if (p->new_segment)
mp_frame_unref(frame);
return true;
}
bool segment_ended = false;
if (frame->type == MP_FRAME_VIDEO) {
struct mp_image *mpi = frame->data;
crazy_video_pts_stuff(p, mpi);
struct demux_packet *ccpkt = new_demux_packet_from_buf(mpi->a53_cc);
if (ccpkt) {
av_buffer_unref(&mpi->a53_cc);
ccpkt->pts = mpi->pts;
ccpkt->dts = mpi->dts;
demuxer_feed_caption(p->header, ccpkt);
}
// Stop hr-seek logic.
if (mpi->pts == MP_NOPTS_VALUE || mpi->pts >= p->start_pts)
p->start_pts = MP_NOPTS_VALUE;
if (mpi->pts != MP_NOPTS_VALUE) {
segment_ended = p->end != MP_NOPTS_VALUE && mpi->pts >= p->end;
if ((p->start != MP_NOPTS_VALUE && mpi->pts < p->start) ||
segment_ended)
{
mp_frame_unref(frame);
goto done;
}
}
} else if (frame->type == MP_FRAME_AUDIO) {
struct mp_aframe *aframe = frame->data;
mp_aframe_clip_timestamps(aframe, p->start, p->end);
double pts = mp_aframe_get_pts(aframe);
if (pts != MP_NOPTS_VALUE && p->start != MP_NOPTS_VALUE)
segment_ended = pts >= p->end;
if (mp_aframe_get_size(aframe) == 0) {
mp_frame_unref(frame);
goto done;
}
} else {
MP_ERR(p, "unknown frame type from decoder\n");
}
done:
return segment_ended;
}
static void correct_video_pts(struct priv *p, struct mp_image *mpi)
{
mpi->pts *= p->play_dir;
if (!p->opts->correct_pts || mpi->pts == MP_NOPTS_VALUE) {
double fps = p->fps > 0 ? p->fps : 25;
if (p->opts->correct_pts) {
if (p->has_broken_decoded_pts <= 1) {
MP_WARN(p, "No video PTS! Making something up. Using "
"%f FPS.\n", fps);
if (p->has_broken_decoded_pts == 1)
MP_WARN(p, "Ignoring further missing PTS warnings.\n");
p->has_broken_decoded_pts++;
}
}
double frame_time = 1.0f / fps;
double base = p->first_packet_pdts;
mpi->pts = p->pts;
if (mpi->pts == MP_NOPTS_VALUE) {
mpi->pts = base == MP_NOPTS_VALUE ? 0 : base;
} else {
mpi->pts += frame_time;
}
}
p->pts = mpi->pts;
}
static void correct_audio_pts(struct priv *p, struct mp_aframe *aframe)
{
double dir = p->play_dir;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
double frame_pts = mp_aframe_get_pts(aframe);
double frame_len = mp_aframe_duration(aframe);
if (frame_pts != MP_NOPTS_VALUE) {
if (dir < 0)
frame_pts = -(frame_pts + frame_len);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
if (p->pts != MP_NOPTS_VALUE)
MP_STATS(p, "value %f audio-pts-err", p->pts - frame_pts);
double diff = fabs(p->pts - frame_pts);
// Attempt to detect jumps in PTS. Even for the lowest sample rates and
// with worst container rounded timestamp, this should be a margin more
// than enough.
if (p->pts != MP_NOPTS_VALUE && diff > 0.1) {
MP_WARN(p, "Invalid audio PTS: %f -> %f\n", p->pts, frame_pts);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
if (diff >= 5) {
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
p->pts_reset = true;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
}
// Keep the interpolated timestamp if it doesn't deviate more
// than 1 ms from the real one. (MKV rounded timestamps.)
if (p->pts == MP_NOPTS_VALUE || diff > 0.001)
p->pts = frame_pts;
}
if (p->pts == MP_NOPTS_VALUE && p->header->missing_timestamps)
p->pts = 0;
mp_aframe_set_pts(aframe, p->pts);
if (p->pts != MP_NOPTS_VALUE)
p->pts += frame_len;
}
static void process_output_frame(struct priv *p, struct mp_frame frame)
{
if (frame.type == MP_FRAME_VIDEO) {
struct mp_image *mpi = frame.data;
correct_video_pts(p, mpi);
if (!mp_image_params_equal(&p->last_format, &mpi->params))
fix_image_params(p, &mpi->params);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
mpi->params = p->fixed_format;
mpi->nominal_fps = p->fps;
} else if (frame.type == MP_FRAME_AUDIO) {
struct mp_aframe *aframe = frame.data;
if (p->play_dir < 0 && !mp_aframe_reverse(aframe))
MP_ERR(p, "Couldn't reverse audio frame.\n");
correct_audio_pts(p, aframe);
}
}
void mp_decoder_wrapper_set_start_pts(struct mp_decoder_wrapper *d, double pts)
{
struct priv *p = d->f->priv;
p->start_pts = pts;
}
static bool is_new_segment(struct priv *p, struct mp_frame frame)
{
if (frame.type != MP_FRAME_PACKET)
return false;
struct demux_packet *pkt = frame.data;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
return (pkt->segmented && (pkt->start != p->start || pkt->end != p->end ||
pkt->codec != p->codec)) ||
(p->play_dir < 0 && pkt->back_restart && p->packet_fed);
}
static void feed_packet(struct priv *p)
{
if (!p->decoder || !mp_pin_in_needs_data(p->decoder->f->pins[0]))
return;
if (p->decoded_coverart.type)
return;
if (!p->packet.type && !p->new_segment) {
p->packet = mp_pin_out_read(p->demux);
if (!p->packet.type)
return;
if (p->packet.type != MP_FRAME_EOF && p->packet.type != MP_FRAME_PACKET) {
MP_ERR(p, "invalid frame type from demuxer\n");
mp_frame_unref(&p->packet);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_internal_mark_failed(p->decf);
return;
}
}
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
if (!p->packet.type)
return;
// Flush current data if the packet is a new segment.
if (is_new_segment(p, p->packet)) {
assert(!p->new_segment);
p->new_segment = p->packet.data;
p->packet = MP_EOF_FRAME;
}
assert(p->packet.type == MP_FRAME_PACKET || p->packet.type == MP_FRAME_EOF);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
struct demux_packet *packet =
p->packet.type == MP_FRAME_PACKET ? p->packet.data : NULL;
// For video framedropping, including parts of the hr-seek logic.
if (p->decoder->control) {
double start_pts = p->start_pts;
if (p->start != MP_NOPTS_VALUE && (start_pts == MP_NOPTS_VALUE ||
p->start > start_pts))
start_pts = p->start;
int framedrop_type = 0;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
if (p->attempt_framedrops)
framedrop_type = 1;
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
if (start_pts != MP_NOPTS_VALUE && packet && p->play_dir > 0 &&
packet->pts < start_pts - .005 && !p->has_broken_packet_pts)
framedrop_type = 2;
p->decoder->control(p->decoder->f, VDCTRL_SET_FRAMEDROP, &framedrop_type);
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
if (!p->dec_dispatch && p->public.recorder_sink)
mp_recorder_feed_packet(p->public.recorder_sink, packet);
double pkt_pts = packet ? packet->pts : MP_NOPTS_VALUE;
double pkt_dts = packet ? packet->dts : MP_NOPTS_VALUE;
if (pkt_pts == MP_NOPTS_VALUE)
p->has_broken_packet_pts = 1;
if (packet && packet->dts == MP_NOPTS_VALUE && !p->codec->avi_dts)
packet->dts = packet->pts;
double pkt_pdts = pkt_pts == MP_NOPTS_VALUE ? pkt_dts : pkt_pts;
if (p->first_packet_pdts == MP_NOPTS_VALUE)
p->first_packet_pdts = pkt_pdts;
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
if (packet && packet->back_preroll) {
p->preroll_discard = true;
packet->pts = packet->dts = MP_NOPTS_VALUE;
}
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
mp_pin_in_write(p->decoder->f->pins[0], p->packet);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
p->packet_fed = true;
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
p->packet = MP_NO_FRAME;
p->packets_without_output += 1;
}
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
static void enqueue_backward_frame(struct priv *p, struct mp_frame frame)
{
bool eof = frame.type == MP_FRAME_EOF;
if (!eof) {
struct dec_wrapper_opts *opts = p->opts;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
uint64_t queue_size = 0;
switch (p->header->type) {
case STREAM_VIDEO: queue_size = opts->video_reverse_size; break;
case STREAM_AUDIO: queue_size = opts->audio_reverse_size; break;
}
if (p->reverse_queue_byte_size >= queue_size) {
MP_ERR(p, "Reversal queue overflow, discarding frame.\n");
mp_frame_unref(&frame);
return;
}
p->reverse_queue_byte_size += mp_frame_approx_size(frame);
}
// Note: EOF (really BOF) is propagated, but not reversed.
MP_TARRAY_INSERT_AT(p, p->reverse_queue, p->num_reverse_queue,
eof ? 0 : p->num_reverse_queue, frame);
p->reverse_queue_complete = eof;
}
static void read_frame(struct priv *p)
{
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct mp_pin *pin = p->decf->ppins[0];
struct mp_frame frame = {0};
if (!p->decoder || !mp_pin_in_needs_data(pin))
return;
if (p->decoded_coverart.type) {
if (p->coverart_returned == 0) {
frame = mp_frame_ref(p->decoded_coverart);
p->coverart_returned = 1;
goto output_frame;
} else if (p->coverart_returned == 1) {
frame = MP_EOF_FRAME;
p->coverart_returned = 2;
goto output_frame;
}
return;
}
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
if (p->reverse_queue_complete && p->num_reverse_queue) {
frame = p->reverse_queue[p->num_reverse_queue - 1];
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
p->num_reverse_queue -= 1;
goto output_frame;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
}
p->reverse_queue_complete = false;
frame = mp_pin_out_read(p->decoder->f->pins[1]);
if (!frame.type)
return;
2023-10-21 02:55:41 +00:00
mp_mutex_lock(&p->cache_lock);
if (p->attached_picture && frame.type == MP_FRAME_VIDEO)
p->decoded_coverart = frame;
if (p->attempt_framedrops) {
int dropped = MPMAX(0, p->packets_without_output - 1);
p->attempt_framedrops = MPMAX(0, p->attempt_framedrops - dropped);
p->dropped_frames += dropped;
}
2023-10-21 02:55:41 +00:00
mp_mutex_unlock(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
if (p->decoded_coverart.type) {
mp_filter_internal_mark_progress(p->decf);
return;
}
p->packets_without_output = 0;
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
if (p->preroll_discard && frame.type != MP_FRAME_EOF) {
double ts = mp_frame_get_pts(frame);
if (ts == MP_NOPTS_VALUE) {
mp_frame_unref(&frame);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_internal_mark_progress(p->decf);
f_decoder_wrapper: hack for discarding preroll in backward playback mode Some audio codecs will discard or cut the first frames when starting decoding. While some of that works through well-defined mechanisms (like initial padding), it's in general very codec/decoder specific, and not really predictable. In addition, libavcodec isn't very good with reporting "dropped" frames (and our internal interface reflects this). It seems our only chance to handle this is through timestamps. In theory, it would be best to discard frames that have timestamps before the "resume" position. But since video has reordered timestamps, we'd need to put some effort into finding this position. The first video packet doesn't necessarily contain this timestamp. (In theory, we could just do this in the demuxer with some trivial additional work, and set it on the packet's kf_seek_pts field. Although this field is supposed to contain just this value, the field is considered demuxer-internal, and I didn't want to make matters worse by reusing it for the interface to the decoder. With some more effort and buffering, we could calculate this value within the decoder, but fuck that.) The approach chosen in this commit is setting the timestamp to NOPTS. This will break in some obscure situations, but backward playback is a pretty obscure feature to begin with, so I considered this a reasonable implementation choice. Before passing a preroll packet to the decoder, its timestamps are set to NOPTS. Frames that are returned from the decoder and have the NOPTS timestamp are considered preroll and are discarded. This happens only during "preroll" mode (preroll_discard==true), so it doesn't affect normal forward playback. It's disabled on the first packet with a timestamp, so it can tolerate some crap even in backward playback mode. We don't check the dts fields out of laziness (decoded audio frames don't even have this field). I considered using an approach using the EDL clipping infrastructure (as mentioned in the last two paragraphs in the commit message of commit " demux_lavf: implement bad hack for backward playback of wav"). This didn't work, and I blamed timestamp rounding within mpv for it. But the problem was actually due to Matroska-rounded timestamps. Since the audio frame size isn't exactly aligned to 1ms, there will be an overlap (or gap) in the timestamps. This overlap is much smaller than 1ms, since it's just the sub-millisecond remainder part of the audio frame size. This makes the timestamps discontinuous and unreliable for the purpose we wanted to use it. We can't just smooth the timestamps in the demuxer either.
2019-05-31 14:07:13 +00:00
return;
}
p->preroll_discard = false;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
}
bool segment_ended = process_decoded_frame(p, &frame);
if (p->play_dir < 0 && frame.type) {
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
enqueue_backward_frame(p, frame);
frame = MP_NO_FRAME;
}
// If there's a new segment, start it as soon as we're drained/finished.
if (segment_ended && p->new_segment) {
struct demux_packet *new_segment = p->new_segment;
p->new_segment = NULL;
reset_decoder(p);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
if (new_segment->segmented) {
if (p->codec != new_segment->codec) {
p->codec = new_segment->codec;
if (!mp_decoder_wrapper_reinit(&p->public))
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_internal_mark_failed(p->decf);
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
}
p->start = new_segment->start;
p->end = new_segment->end;
}
p->reverse_queue_byte_size = 0;
Implement backwards playback See manpage additions. This is a huge hack. You can bet there are shit tons of bugs. It's literally forcing square pegs into round holes. Hopefully, the manpage wall of text makes it clear enough that the whole shit can easily crash and burn. (Although it shouldn't literally crash. That would be a bug. It possibly _could_ start a fire by entering some sort of endless loop, not a literal one, just something where it tries to do work without making progress.) (Some obvious bugs I simply ignored for this initial version, but there's a number of potential bugs I can't even imagine. Normal playback should remain completely unaffected, though.) How this works is also described in the manpage. Basically, we demux in reverse, then we decode in reverse, then we render in reverse. The decoding part is the simplest: just reorder the decoder output. This weirdly integrates with the timeline/ordered chapter code, which also has special requirements on feeding the packets to the decoder in a non-straightforward way (it doesn't conflict, although a bugmessmass breaks correct slicing of segments, so EDL/ordered chapter playback is broken in backward direction). Backward demuxing is pretty involved. In theory, it could be much easier: simply iterating the usual demuxer output backward. But this just doesn't fit into our code, so there's a cthulhu nightmare of shit. To be specific, each stream (audio, video) is reversed separately. At least this means we can do backward playback within cached content (for example, you could play backwards in a live stream; on that note, it disables prefetching, which would lead to losing new live video, but this could be avoided). The fuckmess also meant that I didn't bother trying to support subtitles. Subtitles are a problem because they're "sparse" streams. They need to be "passively" demuxed: you don't try to read a subtitle packet, you demux audio and video, and then look whether there was a subtitle packet. This means to get subtitles for a time range, you need to know that you demuxed video and audio over this range, which becomes pretty messy when you demux audio and video backwards separately. Backward display is the most weird (and potentially buggy) part. To avoid that we need to touch a LOT of timing code, we negate all timestamps. The basic idea is that due to the navigation, all comparisons and subtractions of timestamps keep working, and you don't need to touch every single of them to "reverse" them. E.g.: bool before = pts_a < pts_b; would need to be: bool before = forward ? pts_a < pts_b : pts_a > pts_b; or: bool before = pts_a * dir < pts_b * dir; or if you, as it's implemented now, just do this after decoding: pts_a *= dir; pts_b *= dir; and then in the normal timing/renderer code: bool before = pts_a < pts_b; Consequently, we don't need many changes in the latter code. But some assumptions inhererently true for forward playback may have been broken anyway. What is mainly needed is fixing places where values are passed between positive and negative "domains". For example, seeking and timestamp user display always uses positive timestamps. The main mess is that it's not obvious which domain a given variable should or does use. Well, in my tests with a single file, it suddenly started to work when I did this. I'm honestly surprised that it did, and that I didn't have to change a single line in the timing code past decoder (just something minor to make external/cached text subtitles display). I committed it immediately while avoiding thinking about it. But there really likely are subtle problems of all sorts. As far as I'm aware, gstreamer also supports backward playback. When I looked at this years ago, I couldn't find a way to actually try this, and I didn't revisit it now. Back then I also read talk slides from the person who implemented it, and I'm not sure if and which ideas I might have taken from it. It's possible that the timestamp reversal is inspired by it, but I didn't check. (I think it claimed that it could avoid large changes by changing a sign?) VapourSynth has some sort of reverse function, which provides a backward view on a video. The function itself is trivial to implement, as VapourSynth aims to provide random access to video by frame numbers (so you just request decreasing frame numbers). From what I remember, it wasn't exactly fluid, but it worked. It's implemented by creating an index, and seeking to the target on demand, and a bunch of caching. mpv could use it, but it would either require using VapourSynth as demuxer and decoder for everything, or replacing the current file every time something is supposed to be played backwards. FFmpeg's libavfilter has reversal filters for audio and video. These require buffering the entire media data of the file, and don't really fit into mpv's architecture. It could be used by playing a libavfilter graph that also demuxes, but that's like VapourSynth but worse.
2019-05-18 00:10:51 +00:00
p->reverse_queue_complete = p->num_reverse_queue > 0;
p->packet = MAKE_FRAME(MP_FRAME_PACKET, new_segment);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_internal_mark_progress(p->decf);
}
if (!frame.type) {
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_internal_mark_progress(p->decf); // make it retry
return;
}
output_frame:
process_output_frame(p, frame);
mp_pin_in_write(pin, frame);
}
static void update_queue_config(struct priv *p)
{
if (!p->queue)
return;
struct mp_async_queue_config cfg = {
.max_bytes = p->queue_opts->max_bytes,
.sample_unit = AQUEUE_UNIT_SAMPLES,
.max_samples = p->queue_opts->max_samples,
.max_duration = p->queue_opts->max_duration,
};
mp_async_queue_set_config(p->queue, cfg);
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
static void decf_process(struct mp_filter *f)
{
struct priv *p = f->priv;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
assert(p->decf == f);
if (m_config_cache_update(p->opt_cache))
update_queue_config(p);
feed_packet(p);
read_frame(p);
}
2023-10-21 02:55:41 +00:00
static MP_THREAD_VOID dec_thread(void *ptr)
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
{
struct priv *p = ptr;
char *t_name = "dec/?";
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
switch (p->header->type) {
case STREAM_VIDEO: t_name = "dec/video"; break;
case STREAM_AUDIO: t_name = "dec/audio"; break;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
2023-10-21 02:55:41 +00:00
mp_thread_set_name(t_name);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
while (!p->request_terminate_dec_thread) {
mp_filter_graph_run(p->dec_root_filter);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
update_cached_values(p);
mp_dispatch_queue_process(p->dec_dispatch, INFINITY);
}
2023-10-21 02:55:41 +00:00
MP_THREAD_RETURN();
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
static void public_f_reset(struct mp_filter *f)
{
struct priv *p = f->priv;
assert(p->public.f == f);
if (p->queue) {
mp_async_queue_reset(p->queue);
thread_lock(p);
if (p->dec_root_filter)
mp_filter_reset(p->dec_root_filter);
mp_dispatch_interrupt(p->dec_dispatch);
thread_unlock(p);
mp_async_queue_resume(p->queue);
}
}
static void public_f_destroy(struct mp_filter *f)
{
struct priv *p = f->priv;
assert(p->public.f == f);
if (p->dec_thread_valid) {
assert(p->dec_dispatch);
thread_lock(p);
p->request_terminate_dec_thread = 1;
mp_dispatch_interrupt(p->dec_dispatch);
thread_unlock(p);
2023-10-21 02:55:41 +00:00
mp_thread_join(p->dec_thread);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->dec_thread_valid = false;
}
mp_filter_free_children(f);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
talloc_free(p->dec_root_filter);
talloc_free(p->queue);
2023-10-21 02:55:41 +00:00
mp_mutex_destroy(&p->cache_lock);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
static const struct mp_filter_info decf_filter = {
.name = "decode",
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
.process = decf_process,
.reset = decf_reset,
.destroy = decf_destroy,
};
static const struct mp_filter_info decode_wrapper_filter = {
.name = "decode_wrapper",
.priv_size = sizeof(struct priv),
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
.reset = public_f_reset,
.destroy = public_f_destroy,
};
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
static void wakeup_dec_thread(void *ptr)
{
struct priv *p = ptr;
mp_dispatch_interrupt(p->dec_dispatch);
}
static void onlock_dec_thread(void *ptr)
{
struct priv *p = ptr;
mp_filter_graph_interrupt(p->dec_root_filter);
}
struct mp_decoder_wrapper *mp_decoder_wrapper_create(struct mp_filter *parent,
struct sh_stream *src)
{
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct mp_filter *public_f = mp_filter_create(parent, &decode_wrapper_filter);
if (!public_f)
return NULL;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct priv *p = public_f->priv;
p->public.f = public_f;
2023-10-21 02:55:41 +00:00
mp_mutex_init(&p->cache_lock);
p->opt_cache = m_config_cache_alloc(p, public_f->global, &dec_wrapper_conf);
p->opts = p->opt_cache->opts;
p->header = src;
p->codec = p->header->codec;
p->play_dir = 1;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_add_pin(public_f, MP_PIN_OUT, "out");
if (p->header->type == STREAM_VIDEO) {
p->log = mp_log_new(p, parent->global->log, "!vd");
p->fps = src->codec->fps;
MP_VERBOSE(p, "Container reported FPS: %f\n", p->fps);
if (p->opts->fps_override) {
p->fps = p->opts->fps_override;
MP_INFO(p, "Container FPS forced to %5.3f.\n", p->fps);
MP_INFO(p, "Use --no-correct-pts to force FPS based timing.\n");
}
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->queue_opts = p->opts->vdec_queue_opts;
} else if (p->header->type == STREAM_AUDIO) {
p->log = mp_log_new(p, parent->global->log, "!ad");
p->queue_opts = p->opts->adec_queue_opts;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
} else {
goto error;
}
if (p->queue_opts && p->queue_opts->use_queue) {
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->queue = mp_async_queue_create();
p->dec_dispatch = mp_dispatch_create(p);
p->dec_root_filter = mp_filter_create_root(public_f->global);
mp_filter_graph_set_wakeup_cb(p->dec_root_filter, wakeup_dec_thread, p);
mp_dispatch_set_onlock_fn(p->dec_dispatch, onlock_dec_thread, p);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
struct mp_stream_info *sinfo = mp_filter_find_stream_info(parent);
if (sinfo) {
p->dec_root_filter->stream_info = &p->stream_info;
p->stream_info = (struct mp_stream_info){
.dr_vo = sinfo->dr_vo,
.hwdec_devs = sinfo->hwdec_devs,
};
}
update_queue_config(p);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
}
p->decf = mp_filter_create(p->dec_root_filter ? p->dec_root_filter : public_f,
&decf_filter);
2023-11-18 22:30:42 +00:00
if (!p->decf)
goto error;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->decf->priv = p;
p->decf->log = public_f->log = p->log;
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
mp_filter_add_pin(p->decf, MP_PIN_OUT, "out");
struct mp_filter *demux = mp_demux_in_create(p->decf, p->header);
if (!demux)
goto error;
p->demux = demux->pins[0];
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
decf_reset(p->decf);
if (p->queue) {
struct mp_filter *f_in =
mp_async_queue_create_filter(public_f, MP_PIN_OUT, p->queue);
struct mp_filter *f_out =
mp_async_queue_create_filter(p->decf, MP_PIN_IN, p->queue);
mp_pin_connect(public_f->ppins[0], f_in->pins[0]);
mp_pin_connect(f_out->pins[0], p->decf->pins[0]);
p->dec_thread_valid = true;
2023-10-21 02:55:41 +00:00
if (mp_thread_create(&p->dec_thread, dec_thread, p)) {
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
p->dec_thread_valid = false;
goto error;
}
} else {
mp_pin_connect(public_f->ppins[0], p->decf->pins[0]);
}
public_f_reset(public_f);
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
return &p->public;
error:
player: add optional separate video decoding thread See manpage additions. This has been a topic in MPlayer/mplayer2/mpv since forever. But since libavcodec multi-threaded decoding was added, I've always considered this pointless. libavcodec requires you to "preload" it with packets, and then you can pretty much avoid blocking on it, if decoding is fast enough. But in some cases, a decoupled decoder thread _might_ help. Users have for example come up with cases where decoding video in a separate process and piping it as raw video to mpv helped. (Or my memory is false, and it was about vapoursynth filtering, who knows.) So let's just see whether this helps with anything. Note that this would have been _much_ easier if libavcodec had an asynchronous (or rather, non-blocking) API. It could probably have easily gained that with a small change to its multi-threading code and a small extension to its API, but I guess not. Unfortunately, this uglifies f_decoder_wrapper quite a lot. Part of this is due to annoying corner cases like legacy frame dropping and hardware decoder state. These could probably be prettified later on. There is also a change in playloop.c: this is because there is a need to coordinate playback resets between demuxer thread, decoder thread, and playback logic. I think this SEEK_BLOCK idea worked out reasonably well. There are still a number of problems. For example, if the demuxer cache is full, the decoder thread will simply block hard until the output queue is full, which interferes with seeking. Could also be improved later. Hardware decoding will probably die in a fire, because it will run out of surfaces quickly. We could reduce the queue to size 1... maybe later. We could update the queue options at runtime easily, but currently I'm not going to bother. I could only have put the lavc wrapper itself on a separate thread. But there is some annoying interaction with EDL and backward playback shit, and also you would have had to loop demuxer packets through the playloop, so this sounded less annoying. The food my mother made for us today was delicious. Because audio uses the same code, also for audio (even if completely pointless). Fixes: #6926
2020-02-29 20:40:52 +00:00
talloc_free(public_f);
return NULL;
}
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
void lavc_process(struct mp_filter *f, struct lavc_state *state,
int (*send)(struct mp_filter *f, struct demux_packet *pkt),
int (*receive)(struct mp_filter *f, struct mp_frame *res))
{
if (!mp_pin_in_needs_data(f->ppins[1]))
return;
struct mp_frame frame = {0};
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
int ret_recv = receive(f, &frame);
if (frame.type) {
state->eof_returned = false;
mp_pin_in_write(f->ppins[1], frame);
} else if (ret_recv == AVERROR_EOF) {
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
if (!state->eof_returned)
mp_pin_in_write(f->ppins[1], MP_EOF_FRAME);
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
state->eof_returned = true;
state->packets_sent = false;
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
} else if (ret_recv == AVERROR(EAGAIN)) {
// Need to feed a packet.
frame = mp_pin_out_read(f->ppins[0]);
struct demux_packet *pkt = NULL;
if (frame.type == MP_FRAME_PACKET) {
pkt = frame.data;
} else if (frame.type != MP_FRAME_EOF) {
if (frame.type) {
MP_ERR(f, "unexpected frame type\n");
mp_frame_unref(&frame);
mp_filter_internal_mark_failed(f);
}
return;
} else if (!state->packets_sent) {
// EOF only; just return it, without requiring send/receive to
// pass it through properly.
mp_pin_in_write(f->ppins[1], MP_EOF_FRAME);
return;
}
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
int ret_send = send(f, pkt);
if (ret_send == AVERROR(EAGAIN)) {
// Should never happen, but can happen with broken decoders.
MP_WARN(f, "could not consume packet\n");
mp_pin_out_unread(f->ppins[0], frame);
mp_filter_wakeup(f);
return;
}
state->packets_sent = true;
talloc_free(pkt);
mp_filter_internal_mark_progress(f);
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
} else {
// Decoding error, or hwdec fallback recovery. Just try again.
ad_lavc, vd_lavc: return full error codes to shared decoder loop ad_lavc and vd_lavc use the lavc_process() helper to translate the FFmpeg push/pull API to the internal filter API (which completely mismatch, even though I'm responsible for both, just fucking kill me). This interface was "slightly" too tight. It returned only a bool indicating "progress", which was not enough to handle some cases (see following commit). While we're at it, move all state into a struct. This is only a single bool, but we get the chance to add more if needed. This fixes mpv falling asleep if decoding returns an error during draining. If decoding fails when we already sent EOF, the state machine stopped making progress. This left mpv just sitting around and doing nothing. A test case can be created with: echo $RANDOM >> image.png This makes libavformat read a proper packet plus a packet of garbage. libavcodec will decode a frame, and then return an error code. The lavc_process() wrapper could not deal with this, because there was no way to differentiate between "retry" and "send new packet". Normally, it would send a new packet, so decoding would make progress anyway. If there was "progress", we couldn't just retry, because it'd retry forever. This is made worse by the fact that it tries to decode at least two frames before starting display, meaning it will "sit around and do nothing" before the picture is displayed. Change it so that on error return, "receiving" a frame is retried. This will make it return the EOF, so everything works properly. This is a high-risk change, because all these funny bullshit exceptions for hardware decoding are in the way, and I didn't retest them. For example, if hardware decoding is enabled, it keeps a list of packets, that are fed into the decoder again if hardware decoding fails, and a software fallback is performed. Another case of horrifying accidental complexity. Fixes: #6618
2019-10-24 16:40:46 +00:00
mp_filter_internal_mark_progress(f);
}
}