ffmpeg | branch: master | Dale Curtis <dalecur...@chromium.org> | Thu Apr 23 16:18:18 2020 -0700| [460132c9980f8a1f501a1f69477bca49e1641233] | committer: Anton Khirnov
lavf/mp3dec: don't adjust start time; packets are not adjusted. 7546ac2fee4 made it so that the start_time for mp3 files is adjusted for skip_samples. However, this appears incorrect because subsequent packet timestamps are not adjusted and skip_samples are applied by deleting data from a packet without changing the timestamp. E.g., we are told the start_time is ~25ms and we get a packet with a timestamp of 0 that has had the skip_samples discarded from it. As such rendering engines may incorrectly discard everything prior to the 25ms thinking that is where playback should officially start. Since the samples were deleted without adjusting timestamps though, the true start_time is still 0. Other formats like MP4 with edit lists will adjust both the start time and the timestamps of subsequent packets to avoid this issue. Signed-off-by: Dale Curtis <dalecur...@chromium.org> Signed-off-by: Anton Khirnov <an...@khirnov.net> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=460132c9980f8a1f501a1f69477bca49e1641233 --- libavformat/mp3dec.c | 4 ---- tests/ref/fate/gapless-mp3 | 2 +- 2 files changed, 1 insertion(+), 5 deletions(-) diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index b044679c02..efbf836bcc 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -260,10 +260,6 @@ static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st, st->first_discard_sample = -mp3->end_pad + 528 + 1 + mp3->frames * (int64_t)spf; st->last_discard_sample = mp3->frames * (int64_t)spf; } - if (!st->start_time) - st->start_time = av_rescale_q(st->start_skip_samples, - (AVRational){1, c->sample_rate}, - st->time_base); av_log(s, AV_LOG_DEBUG, "pad %d %d\n", mp3->start_pad, mp3-> end_pad); } diff --git a/tests/ref/fate/gapless-mp3 b/tests/ref/fate/gapless-mp3 index ab4f1a0456..e784391153 100644 --- a/tests/ref/fate/gapless-mp3 +++ b/tests/ref/fate/gapless-mp3 @@ -1,4 +1,4 @@ -44b42cc3a898b45507d856d0813f4f26 *tests/data/fate/gapless-mp3.out-1 +ec876434ed65e338e07234e54d136caf *tests/data/fate/gapless-mp3.out-1 c96c3ae7bd3300fd2f4debac222de5b7 ec876434ed65e338e07234e54d136caf *tests/data/fate/gapless-mp3.out-2 c96c3ae7bd3300fd2f4debac222de5b7 _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
