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mpv/video/decode/dec_video.h
wm4 0af5335383 Rewrite ordered chapters and timeline stuff
This uses a different method to piece segments together. The old
approach basically changes to a new file (with a new start offset) any
time a segment ends. This meant waiting for audio/video end on segment
end, and then changing to the new segment all at once. It had a very
weird impact on the playback core, and some things (like truly gapless
segment transitions, or frame backstepping) just didn't work.

The new approach adds the demux_timeline pseudo-demuxer, which presents
an uniform packet stream from the many segments. This is pretty similar
to how ordered chapters are implemented everywhere else. It also reminds
of the FFmpeg concat pseudo-demuxer.

The "pure" version of this approach doesn't work though. Segments can
actually have different codec configurations (different extradata), and
subtitles are most likely broken too. (Subtitles have multiple corner
cases which break the pure stream-concatenation approach completely.)

To counter this, we do two things:
- Reinit the decoder with each segment. We go as far as allowing
  concatenating files with completely different codecs for the sake
  of EDL (which also uses the timeline infrastructure). A "lighter"
  approach would try to make use of decoder mechanism to update e.g.
  the extradata, but that seems fragile.
- Clip decoded data to segment boundaries. This is equivalent to
  normal playback core mechanisms like hr-seek, but now the playback
  core doesn't need to care about these things.

These two mechanisms are equivalent to what happened in the old
implementation, except they don't happen in the playback core anymore.
In other words, the playback core is completely relieved from timeline
implementation details. (Which honestly is exactly what I'm trying to
do here. I don't think ordered chapter behavior deserves improvement,
even if it's bad - but I want to get it out from the playback core.)

There is code duplication between audio and video decoder common code.
This is awful and could be shareable - but this will happen later.

Note that the audio path has some code to clip audio frames for the
purpose of codec preroll/gapless handling, but it's not shared as
sharing it would cause more pain than it would help.
2016-02-15 21:04:07 +01:00

97 lines
2.8 KiB
C

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MPLAYER_DEC_VIDEO_H
#define MPLAYER_DEC_VIDEO_H
#include <stdbool.h>
#include "demux/stheader.h"
#include "video/hwdec.h"
#include "video/mp_image.h"
struct mp_decoder_list;
struct vo;
struct dec_video {
struct mp_log *log;
struct mpv_global *global;
struct MPOpts *opts;
const struct vd_functions *vd_driver;
struct mp_hwdec_info *hwdec_info; // video output hwdec handles
struct sh_stream *header;
struct mp_codec_params *codec;
char *decoder_desc;
float fps; // FPS from demuxer or from user override
int dropped_frames;
// Internal (shared with vd_lavc.c).
void *priv; // for free use by vd_driver
// Strictly internal (dec_video.c).
// 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 non-sense timestamps.
int has_broken_packet_pts; // <0: uninitialized, 0: no problems, 1: broken
// Final PTS of previously decoded image
double decoded_pts;
struct mp_image_params last_format, fixed_format;
float initial_decoder_aspect;
double start_pts;
double start, end;
struct demux_packet *new_segment;
struct demux_packet *packet;
bool framedrop_enabled;
struct mp_image *cover_art_mpi;
struct mp_image *current_mpi;
int current_state;
};
struct mp_decoder_list *video_decoder_list(void);
bool video_init_best_codec(struct dec_video *d_video);
void video_uninit(struct dec_video *d_video);
void video_work(struct dec_video *d_video);
int video_get_frame(struct dec_video *d_video, struct mp_image **out_mpi);
void video_set_framedrop(struct dec_video *d_video, bool enabled);
void video_set_start(struct dec_video *d_video, double start_pts);
int video_vd_control(struct dec_video *d_video, int cmd, void *arg);
void video_reset(struct dec_video *d_video);
void video_reset_aspect(struct dec_video *d_video);
#endif /* MPLAYER_DEC_VIDEO_H */