avformat/mov: discard data streams with all zero sample_delta

Streams with all zero sample_delta in 'stts' have all zero dts.
They have higher chance be chose by mov_find_next_sample(), which
leads to seek again and again.

For example, GoPro created a 'GoPro SOS' stream:
  Stream #0:4[0x5](eng): Data: none (fdsc / 0x63736466), 13 kb/s (default)
    Metadata:
      creation_time   : 2022-06-21T08:49:19.000000Z
      handler_name    : GoPro SOS

With 'ffprobe -show_frames http://example.com/gopro.mp4', ffprobe
blocks until all samples in 'GoPro SOS' stream are consumed first.

Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>
This commit is contained in:
Zhao Zhili 2022-07-06 15:05:19 +08:00
parent f611255480
commit 811f2f91da
1 changed files with 15 additions and 0 deletions

View File

@ -3062,6 +3062,21 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom)
st->nb_frames= total_sample_count; st->nb_frames= total_sample_count;
if (duration) if (duration)
st->duration= FFMIN(st->duration, duration); st->duration= FFMIN(st->duration, duration);
// All samples have zero duration. They have higher chance be chose by
// mov_find_next_sample, which leads to seek again and again.
//
// It's AVERROR_INVALIDDATA actually, but such files exist in the wild.
// So only mark data stream as discarded for safety.
if (!duration && sc->stts_count &&
st->codecpar->codec_type == AVMEDIA_TYPE_DATA) {
av_log(c->fc, AV_LOG_WARNING,
"All samples in data stream index:id [%d:%d] have zero "
"duration, stream set to be discarded by default. Override "
"using AVStream->discard or -discard for ffmpeg command.\n",
st->index, st->id);
st->discard = AVDISCARD_ALL;
}
sc->track_end = duration; sc->track_end = duration;
return 0; return 0;
} }