From 811f2f91da101db02ee8b1f0e4f6276e5aecda5e Mon Sep 17 00:00:00 2001 From: Zhao Zhili Date: Wed, 6 Jul 2022 15:05:19 +0800 Subject: [PATCH] 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 --- libavformat/mov.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/libavformat/mov.c b/libavformat/mov.c index 29828ea7e6..14550e6456 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -3062,6 +3062,21 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom) st->nb_frames= total_sample_count; if (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; return 0; }