[FFmpeg-trac] #11564(undetermined:new): Chaining 4 video fade filters does not work

[FFmpeg]

#11564: Chaining 4 video fade filters does not work
-------------------------------------+-------------------------------------
             Reporter:  Claudiu      |                     Type:  defect
  Lazar                              |
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:  git-
  undetermined                       |  master
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug: When I try to chain 4 video fade filters the overlay
 isn't shown at all, it works if I removed the last 2 fades.

 How to reproduce:
 {{{
 ffmpeg -report -v 9 -loglevel 99 -y \
   -f lavfi -r 30 -i color=c=blue:s=1920x1080:d=10:rate=30,format=rgba \
   -f lavfi -r 30 -i color=c=yellow:s=300x200:d=10:rate=30,format=rgba \
   -filter_complex \
     '[1]format=rgba,
         fade=t=in:st=0:d=2:alpha=1,
         fade=t=out:st=2:d=2:alpha=1,
         fade=t=in:st=4:d=2:alpha=1,
         fade=t=out:st=6:d=2:alpha=1 [ovl];
      [0][ovl]overlay=shortest=1:format=auto[v]' \
   -map '[v]' -c:v libx264 -pix_fmt yuv420p double.mp4

 ffmpeg version N-119376-g8ea11dcd84
 built on 29-april-2025
 }}}
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/11564>
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