[FFmpeg-trac] #9390(undetermined:new): Wrong FPS used for timecode computation mangles timecodes

[FFmpeg]

#9390: Wrong FPS used for timecode computation mangles timecodes
-------------------------------------+-------------------------------------
             Reporter:  Marcelo      |                     Type:  defect
  Magnasco                           |
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  timecode     |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 ffprobe reports the wrong timecode for footage generated by my GoPro 9
 Black cameras. The error is due to ffprobe/ffmpeg mangling the frame rate
 from 29.97 or 59.94 to 29/1 or 59/1.

 For example, footage with start timecode 10:59:47:14, 29.97fps, is
 reported by ffprobe as having start timecode 11:22:32:16, which is equal
 to (10:59:47:14)*30/29.

 How to reproduce:
 {{{
 % ffprobe GP001.MP4
 where GP001.MP4 is a 29.97fps clip from a GoPro, includes in its output a
 black-backgrounded line
 [mov,mp4,m4a,3gp,3g2,mj2 @ 0x7ffb6b80ac00] Using non-standard frame rate
 29/1

 The incorrect framerate 29 is used to convert the timecode from frames-
 since-midnight to HH:MM:SS:FF format.

 ffmpeg version 4.2.1-tessus
 built with Apple LLVM version 10.0.1 (clang-1001.0.46.4)

 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9390>
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