[FFmpeg-trac] #10106(avfilter:new): Missing frames in shuffleframes filter

[FFmpeg]

#10106: Missing frames in shuffleframes filter
-------------------------------------+-------------------------------------
             Reporter:  nicol        |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avfilter     |                  Version:  git-
             Keywords:               |  master
  shuffleframes                      |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug: When I reorder the telecine source with the
 separatefields and shuffleframes filters, and then restore it with the
 weave filter, some frames are missing. After checking, some of the end
 frames are not output without reordering with shuffleframes.
 How to reproduce:
 {{{
 Make a telecine movie from 0 to 242. 242 is missing half of the field.
 ffmpeg -f lavfi -i
 color=d=10.1:r=24000/1001,drawtext=fontfile=C\\://WINDOWS/Fonts/msgothic.ttc:text='%{n}':fontcolor=yellow:x=(w-tw)/2:y=(h-th)/2:fontsize=96,telecine
 telecine.mp4

 Detelecine with shuffleframes filter only goes up to 239, and the complete
 frames, 240 and 241, are missing.
 ffmpeg -v 9 -loglevel 99 -i telecine.mp4 -vf
 "setparams=tff,separatefields,shuffleframes=0 1 2 3 4 3 6 5 8 9,weave"
 shuffleframes_weave.mp4 -y

 The same without replacing with shuffleframes as well.
 ffmpeg -i telecine.mp4 -vf "setparams=tff,separatefields,shuffleframes=0 1
 2 3 4 5 6 7 8 9,weave" shuffleframes_weave2.mp4

 If you remove the weave filter, you only get up to 239.
 ffmpeg -i telecine.mp4 -vf "setparams=tff,separatefields,shuffleframes=0 1
 2 3 4 5 6 7 8 9" shuffleframes.mp4

 I have no problem until the separatefields filter.
 ffmpeg -i telecine.mp4 -vf "setparams=tff,separatefields"
 separatefields.mp4

 ffmpeg version N-109420-g262e7439c6-20221214 Copyright (c) 2000-2022 the
 FFmpeg developers
 built on ...
 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10106>
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