[FFmpeg-trac] #259(undetermined:open): framerate detection does not work properly. (mkv with default duration != actual average duration)

[FFmpeg]

#259: framerate detection does not work properly. (mkv with default duration !=
actual average duration)
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             Reporter:  mbosner      |                    Owner:
                 Type:  defect       |                   Status:  open
             Priority:  normal       |                Component:
              Version:  unspecified  |  undetermined
             Keywords:  vc1          |               Resolution:
  pulldown mkv fps                   |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  1            |
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Comment (by michael):

 Replying to [comment:10 gjdfgh]:
 > This happens all the time. The most fun issue I've hit was when the
 framerate stored in the file was based on a frame duration... rounded to
 milliseconds. mkvinfo said "Default duration: 42.000ms (23.810
 frames/fields per second for a video track)". Even thouhg the file was
 actually 23.976, and there were frames with 41 ms duration. (Keep in mind
 that Matroska rounds timestamps to milliseconds.)
 >
 > But IMO libavformat shouldn't try to guess this. This belongs into a
 layer somewhere above the decoder. And it would need to be adaptive: what
 do you do about VFR files?

 so what do you suggest ?
 just closing this ticket ? (ATM lavf doesnt really guess it trusts the
 default duration)
 and timestamps should be "correct" so a layer above should be fine as long
 as it doesnt trust the fps

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Ticket URL: <https://trac.ffmpeg.org/ticket/259#comment:11>
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