mpv/audio/decode/ad.h

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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/>.
*/
#ifndef MPLAYER_AD_H
#define MPLAYER_AD_H
#include "common/codecs.h"
#include "demux/stheader.h"
#include "demux/demux.h"
#include "audio/format.h"
#include "audio/audio.h"
#include "dec_audio.h"
core: redo how codecs are mapped, remove codecs.conf Use codec names instead of FourCCs to identify codecs. Rewrite how codecs are selected and initialized. Now each decoder exports a list of decoders (and the codec it supports) via add_decoders(). The order matters, and the first decoder for a given decoder is preferred over the other decoders. E.g. all ad_mpg123 decoders are preferred over ad_lavc, because it comes first in the mpcodecs_ad_drivers array. Likewise, decoders within ad_lavc that are enumerated first by libavcodec (using av_codec_next()) are preferred. (This is actually critical to select h264 software decoding by default instead of vdpau. libavcodec and ffmpeg/avconv use the same method to select decoders by default, so we hope this is sane.) The codec names follow libavcodec's codec names as defined by AVCodecDescriptor.name (see libavcodec/codec_desc.c). Some decoders have names different from the canonical codec name. The AVCodecDescriptor API is relatively new, so we need a compatibility layer for older libavcodec versions for codec names that are referenced internally, and which are different from the decoder name. (Add a configure check for that, because checking versions is getting way too messy.) demux/codec_tags.c is generated from the former codecs.conf (minus "special" decoders like vdpau, and excluding the mappings that are the same as the mappings libavformat's exported RIFF tables). It contains all the mappings from FourCCs to codec name. This is needed for demux_mkv, demux_mpg, demux_avi and demux_asf. demux_lavf will set the codec as determined by libavformat, while the other demuxers have to do this on their own, using the mp_set_audio/video_codec_from_tag() functions. Note that the sh_audio/video->format members don't uniquely identify the codec anymore, and sh->codec takes over this role. Replace the --ac/--vc/--afm/--vfm with new --vd/--ad options, which provide cover the functionality of the removed switched. Note: there's no CODECS_FLAG_FLIP flag anymore. This means some obscure container/video combinations (e.g. the sample Film_200_zygo_pro.mov) are played flipped. ffplay/avplay doesn't handle this properly either, so we don't care and blame ffmeg/libav instead.
2013-02-09 14:15:19 +00:00
struct mp_decoder_list;
dec_audio, ad_lavc: change license to LGPL All relevant authors of the current code have agreed. As always, there are the usual historical artifacts that could be mentioned. For example, there used to be a large number of decoders by various authors who were not asked, but whose code was all 100% removed. (Mostly due to FFmpeg providing all codecs.) One point of contention is that Nick Kurshev might have refactored the old audio decoder code in 2001. Basically, there are hints that it might have been done by him, such as Arpi's commit message stating that the code was imported from MPlayerXP (Nick's fork), or all the files having his name in the "maintainer" field. On the other hand, the murky history of ad.h weakens this - it could be that Arpi started this work, and Nick took it (and possibly finished it). In any case, Nick could not be reached, so there is no agreement for LGPL relicensing from him. We're changing the license anyway, and assume that his change in itself is not copyrightable. He only moved code, and in addition used the equivalent video decoder framework (done by Arpi, who agreed) as template. For example, ad_functions_s was basically vd_functions_s, which the signature of the decode callback changed to the same as audio_decode(). ad_functions_s also had a comment that said it interfaces with "video decoder drivers" (I'm fixing this comment in this commit). I verified that no additional code was added that is copyright-relevant, still in today's code, and not copied from the existing code at the time (either from the previous audio decoder code or the video framework code). What apparently matters here is that none of the old code was not written by Nick, and the authors of the old code have given his agreement, and (probably) that Nick didn't add actual new code (none that would have survived), that was not trivially based on the old one (i.e. no new copyrightable "work"). A copyright expert told me that this kind of change can be considered not relevant for copyright, so here we go. Rewriting this would end with the same code anyway, and the naming conventions can't be copyrighted.
2017-06-14 14:20:56 +00:00
/* interface of audio decoder drivers */
struct ad_functions {
core: redo how codecs are mapped, remove codecs.conf Use codec names instead of FourCCs to identify codecs. Rewrite how codecs are selected and initialized. Now each decoder exports a list of decoders (and the codec it supports) via add_decoders(). The order matters, and the first decoder for a given decoder is preferred over the other decoders. E.g. all ad_mpg123 decoders are preferred over ad_lavc, because it comes first in the mpcodecs_ad_drivers array. Likewise, decoders within ad_lavc that are enumerated first by libavcodec (using av_codec_next()) are preferred. (This is actually critical to select h264 software decoding by default instead of vdpau. libavcodec and ffmpeg/avconv use the same method to select decoders by default, so we hope this is sane.) The codec names follow libavcodec's codec names as defined by AVCodecDescriptor.name (see libavcodec/codec_desc.c). Some decoders have names different from the canonical codec name. The AVCodecDescriptor API is relatively new, so we need a compatibility layer for older libavcodec versions for codec names that are referenced internally, and which are different from the decoder name. (Add a configure check for that, because checking versions is getting way too messy.) demux/codec_tags.c is generated from the former codecs.conf (minus "special" decoders like vdpau, and excluding the mappings that are the same as the mappings libavformat's exported RIFF tables). It contains all the mappings from FourCCs to codec name. This is needed for demux_mkv, demux_mpg, demux_avi and demux_asf. demux_lavf will set the codec as determined by libavformat, while the other demuxers have to do this on their own, using the mp_set_audio/video_codec_from_tag() functions. Note that the sh_audio/video->format members don't uniquely identify the codec anymore, and sh->codec takes over this role. Replace the --ac/--vc/--afm/--vfm with new --vd/--ad options, which provide cover the functionality of the removed switched. Note: there's no CODECS_FLAG_FLIP flag anymore. This means some obscure container/video combinations (e.g. the sample Film_200_zygo_pro.mov) are played flipped. ffplay/avplay doesn't handle this properly either, so we don't care and blame ffmeg/libav instead.
2013-02-09 14:15:19 +00:00
const char *name;
void (*add_decoders)(struct mp_decoder_list *list);
int (*init)(struct dec_audio *da, const char *decoder);
void (*uninit)(struct dec_audio *da);
int (*control)(struct dec_audio *da, int cmd, void *arg);
// Return whether or not the packet has been consumed.
bool (*send_packet)(struct dec_audio *da, struct demux_packet *pkt);
// Return whether decoding is still going on (false if EOF was reached).
// Never returns false & *out set, but can return true with !*out.
bool (*receive_frame)(struct dec_audio *da, struct mp_audio **out);
};
enum ad_ctrl {
ADCTRL_RESET = 1, // flush and reset state, e.g. after seeking
};
#endif /* MPLAYER_AD_H */