"Couldn't determine next keyframe time" on firefox

[legokichi]

related: #3 (comment)

MOZ_LOG_FILE="log.txt" MOZ_LOG="MediaDemuxer:5" /Applications/Firefox.app/Contents/MacOS/firefox-bin

として起動した Firefox 53.0.2 (64 bit) で seekable にした動画を最後まで再生すると

[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11e63f480)::SetNextKeyFrameTime: Couldn't determine next keyframe time  (0 queued)

が発生し、以後再生しようとしても

[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11f008400)::GetBuffered: Duration: 9.371000 StartTime: 0.000000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11f008400)::GetBuffered: limit range to duration, end: 9.466000 duration: 9.371000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11f008400)::GetBuffered: add range 0.000000-9.371000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11e63f480)::Reset: Seek to start point: 0.000000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11f008400)::SeekInternal: Seek Target: 0.000000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11f008400)::SeekInternal: SeekPreroll: 0.080000 StartTime: 0.000000 Adjusted Target: 0.000000
[MediaPlayback #1]: D/MediaDemuxer WebMDemuxer(11e63f480)::SetNextKeyFrameTime: Couldn't determine next keyframe time  (0 queued)

が繰り返されて再生できない。

[legokichi]

http://searchfox.org/mozilla-central/source/dom/media/webm/WebMDemuxer.cpp#1210

  if (frameTime.IsValid()) {
    mNextKeyframeTime.emplace(frameTime);
    WEBM_DEBUG("Next Keyframe %f (%u queued %.02fs)",
               mNextKeyframeTime.value().ToSeconds(),
               uint32_t(mSamples.GetSize()),
               (mSamples.Last()->mTimecode - mSamples.First()->mTimecode).ToSeconds());
  } else {
    WEBM_DEBUG("Couldn't determine next keyframe time  (%u queued)",
               uint32_t(mSamples.GetSize()));
  }

why not valid?

[legokichi]

$ mkvalidator ./test/firefox55nightly.webm
ERR200: Missing element 'Seek' in SeekHead at 55
WRN00C: Unknown element in TrackEntry [56][AA] at 239 (size 4 total 7)
WRN00C: Unknown element in TrackEntry [56][BB] at 246 (size 4 total 7)
WRN861: The SegmentInfo is not referenced in the main SeekHead
WRN861: The TrackInfo is not referenced in the main SeekHead
ERR0B1: SimpleBlock at 57842 track #2 is not a keyframe
ERR0B1: SimpleBlock at 58033 track #2 is not a keyframe
ERR0B1: SimpleBlock at 58145 track #2 is not a keyframe
...
ERR0B1: SimpleBlock at 2750677 track #2 is not a keyframe
ERR0B1: SimpleBlock at 2762102 track #2 is not a keyframe
ERR0B1: SimpleBlock at 2762239 track #2 is not a keyframe

Is this related?

https://github.com/Matroska-Org/foundation-source/blob/91a1cff9725c879486f927e61d17bd4243f677b4/mkvalidator/mkvalidator.c#L780

[legokichi]

Webm video recorded with MediaRecorder cannot be played more than once -
https://bugzilla.mozilla.org/show_bug.cgi?id=1272371

[legokichi]

rec.start.(100); から rec.start.(); にすると確かに original の webm は繰り返し再生できるようになった。
しかし duration だけ、cues だけ、 duration と cues両方追加したものは Couldn't determine next keyframe time が発生して繰り返し再生できなかった。

[legokichi]

timesliceありなしでバイナリの比較が必要

[legokichi]

https://github.com/legokichi/ts-ebml/releases/tag/v2.0.0