[FFmpeg-trac] #10929(undetermined:new): ffmpeg does not take video fps into account when creating mkv file with microdvd subtitles

[FFmpeg]

#10929: ffmpeg does not take video fps into account when creating mkv file with
microdvd subtitles
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             Reporter:  Kicer         |                     Type:  defect
               Status:  new           |                 Priority:  normal
            Component:  undetermined  |                  Version:  6.1
             Keywords:                |               Blocked By:
             Blocking:                |  Reproduced by developer:  0
Analyzed by developer:  0             |
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 Summary of the bug:
 I've tried to create mkv file with subtitles embedded.
 I ran ffmpeg with video and subtitles files as inputs and I got mkv video
 file with invalid subtitles timestamps.

 My video has 60fps and when I run it with a video player and I load
 subtitles file manually then subtitles are ok. Problem appears after merge
 into mkv.

 How to reproduce:
 {{{
 % ffmpeg 60fmp_video.mp4 -i microdvd_subtitles.txt output.mkv
 ffmpeg version n6.1.1 Copyright (c) 2000-2023 the FFmpeg developers
   built with gcc 13.2.1 (GCC) 20230801
 built on arch linux
 }}}

 What I have found is the bug: https://trac.ffmpeg.org/ticket/3287 which
 seems to be exactly the same issue, however it should be fixed.

 Additionaly I have tried to convert my subtitles file into srt file with
 all options that came to my mind which could suggest to ffmpeg that input
 file is for 60fps video, but output subtitles file always ends up with
 incorrect timings (around ~2.5x larger time values, which suggests that
 ~24fps were used as a reference for microdvd file).
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10929>
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