| Message ID | 1471943019-14136-17-git-send-email-erkki.seppala.ext@nokia.com |
|---|---|
| State | Superseded |
| Headers | show |
Le septidi 7 fructidor, an CCXXIV, erkki.seppala.ext@nokia.com a écrit : > From: Erkki Seppälä <erkki.seppala.ext@nokia.com> > > Added support for passing complex channel layout configuration as side > packet data (AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, > AV_PKT_DATA_AUDIO_CHANNEL_PREDEFINED_LAYOUT, > AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT_OBJECT_STRUCTURED) to ISO media files > as specified by ISO/IEC 14496-12. > > This information isn't integrated into the existing channel layout > system though, I think it needs to be. > which is much more restricted compared to what the > standard permits. Certainly, but the bitfield channel layout system is enough for most cases and well tested. Any new system must work with it, not around it. > However, the side packet data is structured so that > it does not require too much ISO base media file format knowledge in > client code. > > This information ends up to an (optional) chnl box in the written file > in an isom track. > > Signed-off-by: Erkki Seppälä <erkki.seppala.ext@nokia.com> > Signed-off-by: OZOPlayer <OZOPL@nokia.com> > --- > libavcodec/avcodec.h | 51 ++++++++++++++++++++++++++++++++- > libavformat/movenc.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++- > 2 files changed, 130 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h > index 36c85e9..6c64e6a 100644 > --- a/libavcodec/avcodec.h > +++ b/libavcodec/avcodec.h > @@ -1365,6 +1365,35 @@ typedef struct AVTrackReferences { > /** followed by: int tracks[nb_tracks]; -- tracks this track refers to */ > } AVTrackReferences; > > +/** Describes the speaker position of a single audio channel of a single track */ Please follow the surrounding style for Doxygen comments: /** and */ on a separate line, * at the beginning of each line. > +typedef struct AVAudioTrackChannelPosition { > + int speaker_position; /** an OutputChannelPosition from ISO/IEC 23001-8 */ I think most our API users and even developers have better use for 158 Swiss Francs than feeding the ISO. Please make the API self-sufficient; I suggest an enum. > + > + /** The following are used if speaker_position == 126 */ > + int azimuth; > + int elevation; Please document the units and references. Also, since it is repeated and packed, using a small type would make sense here if possible. > +} AVAudioTrackChannelPosition; > + > +/** Describes the channel layout (ie. speaker position) of a single audio track */ > +typedef struct AVAudioTrackChannelLayout { > + int nb_positions; > + /** followed by: AVAudioTrackChannelPosition positions[nb_positions]; */ AVAudioTrackChannelPosition positions[0]; That way, computing the address is taken care of by the compiler without tricky pointer arithmetic, including alignment requirements. (We already use 0-sized final arrays once in vaapi_encode.h; since VA API is for Linux and BSD, it does not probe the crappy proprietary compilers support it. In that case, using 1 instead of 0 is fine.) > +} AVAudioTrackChannelLayout; > + > +/** Describes the channel layout based on predefined layout of a single track > + by providing the layout and the list of channels are are omitted */ Could you make that clearer? > +typedef struct AVAudioTrackChannelPredefinedLayout { > + int layout; /** ChannelConfiguration from ISO/IEC 23001-8 */ > + int nb_omitted_channels; > + /** followed by: char omitted_channels[nb_omitted_channels]; - non-zero indicates the channel is omitted */ Is there a reasonable upper bound to nb_omitted_channels? Also, I think the naming is inconsistent: if nb_omitted_channels = 3 and omitted_channels[] = { 1, 0, 1 }, there are only two omitted channels, not three. > +} AVAudioTrackChannelPredefinedLayout; > + > +/** Describes the channel layout to be object-sturctued with given > + number of objects */ Please make that clearer. > +typedef struct AVAudioTrackChannelLayoutObjectStructured { > + int object_count; > +} AVAudioTrackChannelLayoutObjectStructured; > + > enum AVPacketSideDataType { > AV_PKT_DATA_PALETTE, > > @@ -1556,7 +1585,27 @@ enum AVPacketSideDataType { > * Configured the timed metadata parameters, such as the uri and > * meta data configuration. The key is of type AVTimedMetadata. > */ > - AV_PKT_DATA_TIMED_METADATA_INFO > + AV_PKT_DATA_TIMED_METADATA_INFO, > + > + /** > + * Channel layout, describing the position of spakers for the > + * channels of a track, following the structure > + * AVAudioTrackChannelLayout. > + */ > + AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, I think it would be a good idea if the name of the side data matches the name of the structure as much as possible: Track -> _TRACK_. Ditto for the others. Would it make sense to have a single side data type and an integer field at the beginning announcing the type of the rest: typedef struct AVComplexChannelLayout { enum AVComplexChannelLayoutType type; union { uint64_t bitmask; AVAudioTrackChannelLayout complete; AVAudioTrackChannelPredefinedLayout predefined; AVAudioTrackChannelLayoutObjectStructured object; } layout; }; > + > + /** > + * Predefined channel layout, describing the position of spakers > + * for the channels of a track, following the structure > + * AVAudioTrackChannelPredefinedLayout. > + */ > + AV_PKT_DATA_AUDIO_CHANNEL_PREDEFINED_LAYOUT, > + > + /** > + * The channel layout is object structured with the number of objects in > + * AVAudioTrackChannelLayoutObjectStructured > + */ > + AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT_OBJECT_STRUCTURED Missing final comma (ditto in the patch adding AV_PKT_DATA_TIMED_METADATA_INFO; blame to Neil for not adding it to AV_PKT_DATA_MASTERING_DISPLAY_METADATA). > }; > > #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED > diff --git a/libavformat/movenc.c b/libavformat/movenc.c > index ff4bf85..9606918 100644 > --- a/libavformat/movenc.c > +++ b/libavformat/movenc.c I can not comment on that file. Regards,
On 08/23/2016 08:49 PM, Nicolas George wrote: >> + int speaker_position; /** an OutputChannelPosition from ISO/IEC 23001-8 */ > > I think most our API users and even developers have better use for 158 Swiss > Francs than feeding the ISO. Please make the API self-sufficient; I suggest > an enum. I'll introduce an enumeration AVSpeakerPosition. However, the spec is available publicly at http://standards.iso.org/ittf/PubliclyAvailableStandards/c062088_ISO_IEC_23001-8_2013.zip . (And the table of output channel positions starts at page 24.) > Le septidi 7 fructidor, an CCXXIV, erkki.seppala.ext@nokia.com a écrit : >> From: Erkki Seppälä <erkki.seppala.ext@nokia.com> >> >> Added support for passing complex channel layout configuration as side >> packet data (AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, >> AV_PKT_DATA_AUDIO_CHANNEL_PREDEFINED_LAYOUT, >> AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT_OBJECT_STRUCTURED) to ISO media files >> as specified by ISO/IEC 14496-12. >> >> This information isn't integrated into the existing channel layout >> system though, > > I think it needs to be. Unfortunately properly integrating this information into FFmpeg sounds larger than the scope of my project. I imagine this still would be very helpful base work should such information be actually supported by various parts of FFmpeg. A special bit in the AV_CH_LAYOUT_* could be used for indicating that a special layout exists, but that information by itself is nowhere enough to work with this data with ie. in the functions available in channel_layout.c. And if codec or client code is able to deal with the advanced channel layout configurations, they also have access to this side data. I also believe is is easier to study more deeper integration once a non-intrusive possibility to work with advanced ISOBMFF channel layouts exists. Here is how the mapping on speaker position level might be done: /** Speaker positions according to ISO/IEC 23001-8 */ enum AVSpeakerPosition { ! AV_SPEAKER_POSITION_L = 0, /// Left front ! AV_SPEAKER_POSITION_R = 1, /// Right front AV_SPEAKER_POSITION_C = 2, /// Centre front AV_SPEAKER_POSITION_LFE = 3, /// Low frequency enhancement AV_SPEAKER_POSITION_LS = 4, /// Left surround AV_SPEAKER_POSITION_RS = 5, /// Right surround ! AV_SPEAKER_POSITION_LC = 6, /// Left front centre ! AV_SPEAKER_POSITION_RC = 7, /// Right front centre AV_SPEAKER_POSITION_LSR = 8, /// Rear surround left AV_SPEAKER_POSITION_RSR = 9, /// Rear surround right AV_SPEAKER_POSITION_CS = 10, /// Rear centre AV_SPEAKER_POSITION_LSD = 11, /// Left surround direct AV_SPEAKER_POSITION_RSD = 12, /// Right surround direct AV_SPEAKER_POSITION_LSS = 13, /// Left side surround AV_SPEAKER_POSITION_RSS = 14, /// Right side surround ! AV_SPEAKER_POSITION_LW = 15, /// Left wide front ! AV_SPEAKER_POSITION_RW = 16, /// Right wide front AV_SPEAKER_POSITION_LV = 17, /// Left front vertical height AV_SPEAKER_POSITION_RV = 18, /// Right front vertical height AV_SPEAKER_POSITION_CV = 19, /// Centre front vertical height AV_SPEAKER_POSITION_LVR = 20, /// Left surround vertical height rear AV_SPEAKER_POSITION_RVR = 21, /// Right surround vertical height rear AV_SPEAKER_POSITION_CVR = 22, /// Centre vertical height rear AV_SPEAKER_POSITION_LVSS = 23, /// Left vertical height side surround AV_SPEAKER_POSITION_RVSS = 24, /// Right vertical height side surround AV_SPEAKER_POSITION_TS = 25, /// Top centre surround AV_SPEAKER_POSITION_LFE2 = 26, /// E2 Low frequency enhancement 2 AV_SPEAKER_POSITION_LB = 27, /// Left front vertical bottom AV_SPEAKER_POSITION_RB = 28, /// Right front vertical bottom AV_SPEAKER_POSITION_CB = 29, /// Centre front vertical bottom AV_SPEAKER_POSITION_LVS = 30, /// Left vertical height surround AV_SPEAKER_POSITION_RVS = 31, /// Right vertical height surround /// 32-45 Reserved AV_SPEAKER_POSITION_LFE3 = 36, /// E3 Low frequency enhancement 3 AV_SPEAKER_POSITION_LEOS = 37, /// Left edge of screen AV_SPEAKER_POSITION_REOS = 38, /// Right edge of screen AV_SPEAKER_POSITION_HWBCAL = 39, /// half-way between centre of screen and left edge of screen AV_SPEAKER_POSITION_HWBCAR = 40, /// half-way between centre of screen and right edge of screen AV_SPEAKER_POSITION_LBS = 41, /// Left back surround AV_SPEAKER_POSITION_RBS = 42, /// Right back surround /// 43–125 Reserved AV_SPEAKER_POSITION_EXPL = 126, /// Explicit position (see text) /// 127 Unknown / undefined }; I suppose if this is preferred, then one for 23001-8 channel layouts would be preferred as well.. It does seem confusing though that similar #defines are available in channel_layout.h and I am a bit uncertain of a 1:1 mapping between the two. I've marked in above with ! the ones that I found a match from the defines: AV_CH_FRONT_LEFT AV_SPEAKER_POSITION_L AV_CH_FRONT_RIGHT AV_SPEAKER_POSITION_R AV_CH_FRONT_CENTER AV_SPEAKER_POSITION_LC AV_CH_LOW_FREQUENCY AV_SPEAKER_POSITION_LFE AV_CH_BACK_LEFT AV_SPEAKER_POSITION_LBS AV_CH_BACK_RIGHT AV_SPEAKER_POSITION_RBS AV_CH_FRONT_LEFT_OF_CENTER AV_SPEAKER_POSITION_LC AV_CH_FRONT_RIGHT_OF_CENTER AV_SPEAKER_POSITION_RC AV_CH_BACK_CENTER AV_CH_SIDE_LEFT AV_SPEAKER_POSITION_LSS AV_CH_SIDE_RIGHT AV_SPEAKER_POSITION_RSS AV_CH_TOP_CENTER AV_SPEAKER_POSITION_TS AV_CH_TOP_FRONT_LEFT AV_CH_TOP_FRONT_CENTER AV_CH_TOP_FRONT_RIGHT AV_CH_TOP_BACK_LEFT AV_CH_TOP_BACK_CENTER AV_CH_TOP_BACK_RIGHT AV_CH_STEREO_LEFT AV_CH_STEREO_RIGHT AV_CH_WIDE_LEFT AV_SPEAKER_POSITION_LW AV_CH_WIDE_RIGHT AV_SPEAKER_POSITION_RW AV_CH_SURROUND_DIRECT_LEFT AV_SPEAKER_POSITION_LSD AV_CH_SURROUND_DIRECT_RIGHT AV_SPEAKER_POSITION_RSD AV_CH_LOW_FREQUENCY_2 AV_SPEAKER_POSITION_LFE2 If this approach were taken, then the missing speakers positions (channels?) would need to be added, conversion maps for 23001-8 would need to be implemented (and probably refusing if there are non-mappable positions). Then layout bitmaps would be mapped into 23001-8 ones or if the layout cannot be found, a custom one generated.. Personally I don't mind how separate&simple this system still is :). >> which is much more restricted compared to what the >> standard permits. > > Certainly, but the bitfield channel layout system is enough for most cases > and well tested. Any new system must work with it, not around it. But as you may agree, such a modification would not be small. Certainly not one I would try as my first feature to FFmpeg. > Please follow the surrounding style for Doxygen comments: /** and */ on a > separate line, * at the beginning of each line. Oops. I'll fix those. >> + /** The following are used if speaker_position == 126 */ >> + int azimuth; >> + int elevation; > > Please document the units and references. Done. > Also, since it is repeated and packed, using a small type would make sense > here if possible. I'll use the same types as in the headers: int16_t and int8_t. >> +} AVAudioTrackChannelPosition; >> + >> +/** Describes the channel layout (ie. speaker position) of a single audio track */ >> +typedef struct AVAudioTrackChannelLayout { >> + int nb_positions; > >> + /** followed by: AVAudioTrackChannelPosition positions[nb_positions]; */ > > AVAudioTrackChannelPosition positions[0]; > > That way, computing the address is taken care of by the compiler without > tricky pointer arithmetic, including alignment requirements. Actually this is the way I had it in the first place, but compiler warnings convinced me not to do it. If I'll use positions[1] the allocations will end up slightly too large unless without slightly convoluted code. Is there a preferred way? It doesn't seem like foo[1] is used anywhere. > (We already use 0-sized final arrays once in vaapi_encode.h; since VA API is > for Linux and BSD, it does not probe the crappy proprietary compilers > support it. In that case, using 1 instead of 0 is fine.) In particular I don't want to do it conditionally :). > >> +} AVAudioTrackChannelLayout; >> + > >> +/** Describes the channel layout based on predefined layout of a single track >> + by providing the layout and the list of channels are are omitted */ > > Could you make that clearer? > >> +typedef struct AVAudioTrackChannelPredefinedLayout { >> + int layout; /** ChannelConfiguration from ISO/IEC 23001-8 */ > >> + int nb_omitted_channels; >> + /** followed by: char omitted_channels[nb_omitted_channels]; - non-zero indicates the channel is omitted */ > > Is there a reasonable upper bound to nb_omitted_channels? Yes, ISOBMFF supports only 64 channels for this mask. But perhaps even a higher number is usable for some special case scenarios, not involving ISOBMFF? > Also, I think the naming is inconsistent: if nb_omitted_channels = 3 and > omitted_channels[] = { 1, 0, 1 }, there are only two omitted channels, not > three. I agree that it seems a bit inconsistent.. Would an integer array enumerating the omitted channels be better? Of course this whole problem goes away if the structure is fixed-size (ie. uint8_t omitted_channels_bitmask[64 / 8] or the uint64_t you suggested). >> enum AVPacketSideDataType { >> AV_PKT_DATA_PALETTE, >> >> @@ -1556,7 +1585,27 @@ enum AVPacketSideDataType { >> * Configured the timed metadata parameters, such as the uri and >> * meta data configuration. The key is of type AVTimedMetadata. >> */ >> - AV_PKT_DATA_TIMED_METADATA_INFO >> + AV_PKT_DATA_TIMED_METADATA_INFO, >> + >> + /** >> + * Channel layout, describing the position of spakers for the >> + * channels of a track, following the structure > >> + * AVAudioTrackChannelLayout. >> + */ >> + AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, > > I think it would be a good idea if the name of the side data matches the > name of the structure as much as possible: Track -> _TRACK_. Ditto for the > others. > > Would it make sense to have a single side data type and an integer field at > the beginning announcing the type of the rest: > > typedef struct AVComplexChannelLayout { > enum AVComplexChannelLayoutType type; > union { > uint64_t bitmask; > AVAudioTrackChannelLayout complete; > AVAudioTrackChannelPredefinedLayout predefined; > AVAudioTrackChannelLayoutObjectStructured object; > } layout; > }; It does seem nice. The actual structs/enums might look like this: typedef struct AVAudioTrackChannelLayout { int nb_positions; /** Contains nb_positions entries*/ AVAudioTrackChannelPosition positions[1]; } AVAudioTrackChannelLayout; typedef struct AVAudioTrackChannelPredefinedLayout { int layout; /** ChannelConfiguration from ISO/IEC 23001-8 */ uint64_t omitted_channels; } AVAudioTrackChannelPredefinedLayout; typedef enum AVComplexAudioTrackChannelLayoutType { AV_COMPLEX_CHANNEL_LAYOUT_PREDEFINED, AV_COMPLEX_CHANNEL_LAYOUT_CUSTOM } AVComplexAudioTrackChannelLayoutType; typedef struct AVComplexAudioChannelLayout { enum AVComplexAudioTrackChannelLayoutType type; union { AVAudioTrackChannelPredefinedLayout predefined; AVAudioTrackChannelLayout complete; }; } AVComplexAudioChannelLayout; enum AVPacketSideDataType { ... /** * Channel layout, describing the position of speakers for the * channels of a track, following the structure * AVComplexAudioChannelLayout. */ AV_PKT_DATA_COMPLEX_AUDIO_CHANNEL_LAYOUT, /** * The channel layout is object structured with the number of objects in an int (may accompany AV_PKT_DATA_COMPLEX_AUDIO_CHANNEL_LAYOUT) */ AV_PKT_DATA_COMPLEX_AUDIO_TRACK_CHANNEL_LAYOUT_OBJECT_STRUCTURED, } AVPacketSideDataType; I'm not super happy about the long names (though tempted to s/AVAudio/AVComplexAudio/), but what is the alternative :). Thanks for reviewing and feedback!
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h index 36c85e9..6c64e6a 100644 --- a/libavcodec/avcodec.h +++ b/libavcodec/avcodec.h @@ -1365,6 +1365,35 @@ typedef struct AVTrackReferences { /** followed by: int tracks[nb_tracks]; -- tracks this track refers to */ } AVTrackReferences; +/** Describes the speaker position of a single audio channel of a single track */ +typedef struct AVAudioTrackChannelPosition { + int speaker_position; /** an OutputChannelPosition from ISO/IEC 23001-8 */ + + /** The following are used if speaker_position == 126 */ + int azimuth; + int elevation; +} AVAudioTrackChannelPosition; + +/** Describes the channel layout (ie. speaker position) of a single audio track */ +typedef struct AVAudioTrackChannelLayout { + int nb_positions; + /** followed by: AVAudioTrackChannelPosition positions[nb_positions]; */ +} AVAudioTrackChannelLayout; + +/** Describes the channel layout based on predefined layout of a single track + by providing the layout and the list of channels are are omitted */ +typedef struct AVAudioTrackChannelPredefinedLayout { + int layout; /** ChannelConfiguration from ISO/IEC 23001-8 */ + int nb_omitted_channels; + /** followed by: char omitted_channels[nb_omitted_channels]; - non-zero indicates the channel is omitted */ +} AVAudioTrackChannelPredefinedLayout; + +/** Describes the channel layout to be object-sturctued with given + number of objects */ +typedef struct AVAudioTrackChannelLayoutObjectStructured { + int object_count; +} AVAudioTrackChannelLayoutObjectStructured; + enum AVPacketSideDataType { AV_PKT_DATA_PALETTE, @@ -1556,7 +1585,27 @@ enum AVPacketSideDataType { * Configured the timed metadata parameters, such as the uri and * meta data configuration. The key is of type AVTimedMetadata. */ - AV_PKT_DATA_TIMED_METADATA_INFO + AV_PKT_DATA_TIMED_METADATA_INFO, + + /** + * Channel layout, describing the position of spakers for the + * channels of a track, following the structure + * AVAudioTrackChannelLayout. + */ + AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, + + /** + * Predefined channel layout, describing the position of spakers + * for the channels of a track, following the structure + * AVAudioTrackChannelPredefinedLayout. + */ + AV_PKT_DATA_AUDIO_CHANNEL_PREDEFINED_LAYOUT, + + /** + * The channel layout is object structured with the number of objects in + * AVAudioTrackChannelLayoutObjectStructured + */ + AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT_OBJECT_STRUCTURED }; #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED diff --git a/libavformat/movenc.c b/libavformat/movenc.c index ff4bf85..9606918 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -557,6 +557,83 @@ static unsigned compute_avg_bitrate(MOVTrack *track) return size * 8 * track->timescale / track->track_duration; } +static int mov_write_chnl_tag(AVIOContext *pb, MOVTrack *track) +{ + AVAudioTrackChannelLayout *layout = + (void*) av_stream_get_side_data(track->st, AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT, + NULL); + + AVAudioTrackChannelPredefinedLayout *predefLayout = + (void*) av_stream_get_side_data(track->st, AV_PKT_DATA_AUDIO_CHANNEL_PREDEFINED_LAYOUT, + NULL); + + AVAudioTrackChannelLayoutObjectStructured *objectStructured = + (void*) av_stream_get_side_data(track->st, AV_PKT_DATA_AUDIO_CHANNEL_LAYOUT_OBJECT_STRUCTURED, + NULL); + + if (!layout && !predefLayout && !objectStructured) { + return 0; + } else { + int64_t pos = avio_tell(pb); + + int channel_structured = !!layout || !!predefLayout; + + // ChannelConfiguration from ISO/IEC 23001-8 + int defined_layout = predefLayout ? predefLayout->layout : 0; + int channel_count = track->par->channels; + + int object_structured = !!objectStructured; + int object_count = objectStructured ? objectStructured->object_count : 0; + + int stream_structure = (channel_structured << 0) | (object_structured << 1); + + avio_wb32(pb, 0); // size + ffio_wfourcc(pb, "chnl"); + avio_wb32(pb, 0); // Version + + avio_w8(pb, stream_structure); + + if (channel_structured) { + avio_w8(pb, defined_layout); + if (defined_layout == 0) { + AVAudioTrackChannelPosition* positions; + int i; + av_assert0(layout); + av_assert0(layout->nb_positions >= channel_count); + + positions = (void*) (layout + 1); + + for (i = 0; i < channel_count; ++i) { + AVAudioTrackChannelPosition *pos = &positions[i]; + avio_w8(pb, pos->speaker_position); + if (pos->speaker_position == 126) { + avio_wb16(pb, pos->azimuth); + avio_w8(pb, pos->elevation); + } + } + } else { + int omitted_channels_map[64 / 8] = { 0 }; + char* omitted_channels; + int i; + av_assert0(predefLayout); + + omitted_channels = (void*) (predefLayout + 1); + + for (i = 0; i < FFMIN(64, predefLayout->nb_omitted_channels); ++i) { + omitted_channels_map[i / 8] |= + ((!!omitted_channels[i]) << (i % 8)); + } + for (i = 0; i < 64 / 8; ++i) + avio_w8(pb, omitted_channels_map[i]); + } + } + if (object_structured) + avio_w8(pb, object_count); + + return update_size(pb, pos); + } +} + static int mov_write_esds_tag(AVIOContext *pb, MOVTrack *track) // Basic { AVCPBProperties *props; @@ -996,8 +1073,10 @@ static int mov_write_audio_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContex (mov_pcm_le_gt16(track->par->codec_id) && version==1) || (mov_pcm_be_gt16(track->par->codec_id) && version==1))) mov_write_wave_tag(s, pb, track); - else if (track->tag == MKTAG('m','p','4','a')) + else if (track->tag == MKTAG('m','p','4','a')) { + mov_write_chnl_tag(pb, track); mov_write_esds_tag(pb, track); + } else if (track->par->codec_id == AV_CODEC_ID_AMR_NB) mov_write_amr_tag(pb, track); else if (track->par->codec_id == AV_CODEC_ID_AC3)