[Bug 797262] MP4(H.264+MP3) file can't be seeked anymore since 1.5.x

[GStreamer (GNOME Bugzilla)]

https://bugzilla.gnome.org/show_bug.cgi?id=797262

--- Comment #28 from Seungha Yang <pudding8757 at gmail.com> ---
(In reply to Sebastian Dröge (slomo) from comment #27)
> Comment on attachment 374125 [details] [review]
> qtdemux: Ignore corrupted CTTS box
> 
> Why >2x? Even >1x the stream duration would seem wrong, at most it could in
> theory be the stream duration or not?

Actually, I could not find any reference (from spec.) that defines the allowed
sample_offset bounds exactly in this case. So, 2x is a just "magic number" to
avoid some possible edge cases, such as one video sample only case, etc.

Note that ffmpeg is avoiding this issue as follows.
"If the sample_offset is sufficiently large and this entry is not the last...
then ignore this!". I don't know where "-(1<<28)" came from... 
if (FFNABS(duration) < -(1<<28) && i+2<entries) {
  av_log(c->fc, AV_LOG_WARNING, "CTTS invalid\n");
  av_freep(&sc->ctts_data);
  sc->ctts_count = 0;
  return 0;
}

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.