Anton Khirnov: > Quoting Andreas Rheinhardt (2021-02-22 05:05:29) >> Andreas Rheinhardt: >>> Needs a CountedElement in order to distinguish the case of the element >>> not being present and the element being present with a value of zero. >>> >>> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> >>> --- >>> libavformat/matroska.h | 1 + >>> libavformat/matroskadec.c | 7 ++++++- >>> 2 files changed, 7 insertions(+), 1 deletion(-) >>> >>> diff --git a/libavformat/matroska.h b/libavformat/matroska.h >>> index 191c4f6149..8ab87eff20 100644 >>> --- a/libavformat/matroska.h >>> +++ b/libavformat/matroska.h >>> @@ -100,6 +100,7 @@ >>> #define MATROSKA_ID_TRACKFLAGDEFAULT 0x88 >>> #define MATROSKA_ID_TRACKFLAGFORCED 0x55AA >>> #define MATROSKA_ID_TRACKFLAGLACING 0x9C >>> +#define MATROSKA_ID_TRACKFLAGORIGINAL 0x55AE >>> #define MATROSKA_ID_TRACKMINCACHE 0x6DE7 >>> #define MATROSKA_ID_TRACKMAXCACHE 0x6DF8 >>> #define MATROSKA_ID_TRACKDEFAULTDURATION 0x23E383 >>> diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c >>> index fa266fcaec..f15bf8f9d2 100644 >>> --- a/libavformat/matroskadec.c >>> +++ b/libavformat/matroskadec.c >>> @@ -251,6 +251,7 @@ typedef struct MatroskaTrack { >>> uint64_t flag_default; >>> uint64_t flag_forced; >>> uint64_t flag_comment; >>> + CountedElement flag_original; >>> uint64_t seek_preroll; >>> MatroskaTrackVideo video; >>> MatroskaTrackAudio audio; >>> @@ -410,7 +411,7 @@ typedef struct MatroskaDemuxContext { >>> // incomplete type (6.7.2 in C90, 6.9.2 in C99). >>> // Removing the sizes breaks MSVC. >>> static EbmlSyntax ebml_syntax[3], matroska_segment[9], >>> matroska_track_video_color[15], matroska_track_video[19], >>> - matroska_track[28], matroska_track_encoding[6], >>> matroska_track_encodings[2], >>> + matroska_track[29], matroska_track_encoding[6], >>> matroska_track_encodings[2], >>> matroska_track_combine_planes[2], >>> matroska_track_operation[2], matroska_tracks[2], >>> matroska_attachments[2], matroska_chapter_entry[9], >>> matroska_chapter[6], matroska_chapters[2], >>> matroska_index_entry[3], matroska_index[2], >>> matroska_tag[3], matroska_tags[2], matroska_seekhead[2], >>> @@ -575,6 +576,7 @@ static EbmlSyntax matroska_track[] = { >>> { MATROSKA_ID_TRACKFLAGCOMMENTARY, EBML_UINT, 0, 0, >>> offsetof(MatroskaTrack, flag_comment), { .u = 0 } }, >>> { MATROSKA_ID_TRACKFLAGDEFAULT, EBML_UINT, 0, 0, >>> offsetof(MatroskaTrack, flag_default), { .u = 1 } }, >>> { MATROSKA_ID_TRACKFLAGFORCED, EBML_UINT, 0, 0, >>> offsetof(MatroskaTrack, flag_forced), { .u = 0 } }, >>> + { MATROSKA_ID_TRACKFLAGORIGINAL, EBML_UINT, 1, 0, >>> offsetof(MatroskaTrack, flag_original), {.u = 0 } }, >>> { MATROSKA_ID_TRACKVIDEO, EBML_NEST, 0, 0, >>> offsetof(MatroskaTrack, video), { .n = matroska_track_video } }, >>> { MATROSKA_ID_TRACKAUDIO, EBML_NEST, 0, 0, >>> offsetof(MatroskaTrack, audio), { .n = matroska_track_audio } }, >>> { MATROSKA_ID_TRACKOPERATION, EBML_NEST, 0, 0, >>> offsetof(MatroskaTrack, operation), { .n = matroska_track_operation } }, >>> @@ -2746,6 +2748,9 @@ static int matroska_parse_tracks(AVFormatContext *s) >>> st->disposition |= AV_DISPOSITION_FORCED; >>> if (track->flag_comment) >>> st->disposition |= AV_DISPOSITION_COMMENT; >>> + if (track->flag_original.count > 0) >>> + st->disposition |= track->flag_original.el.u ? >>> AV_DISPOSITION_ORIGINAL >>> + : >>> AV_DISPOSITION_DUB; >>> >>> if (!st->codecpar->extradata) { >>> if (extradata) { >>> >> Ridley Combs reviewed this set via IRC and approved it with one >> exception: It makes no sense to use AV_DISPOSITION_DUB for something >> else than an audio track, so if FlagOriginal is set to zero (meaning the >> track is not in the content's original language), it should not be >> exported at all. And the muxer should ignore AV_DISPOSITION_DUB for >> non-audio-tracks. How do others think about this? > > AV_DISPOSITION_DUB is not documented, so you can interpret it pretty > widely. One interpretation that I can think of is: > - there are two audio tracks - let's say japanese original and english > dub > - there are also two english subtitle tracks: > * one that translates everything, meant to be used with the original > audio; > * the other one translating just the text in the video (and possibly > things that were meant to be subtitled in the original, like > speech in Klingon), meant to be used with the english dub > > Then it can make sense to tag the second subtitle track with > AV_DISPOSITION_DUB to indicate it is supposed to be used with the dubbed > audio track. > That is also pretty much what I thought; furthermore, I'd really hate if something was lost during a remuxing. I will therefore apply this as-is tomorrow unless more comes up. (I will leave the matroska-wtv-remux fate test out of this for reasons explained here: https://ffmpeg.org/pipermail/ffmpeg-devel/2021-February/276986.html)
- Andreas _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".