[FFmpeg-trac] #10787(undetermined:new): PNG output has cICP and gAMA chunks

[FFmpeg]

#10787: PNG output has cICP and gAMA chunks
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             Reporter:  Simon         |                     Type:  defect
               Status:  new           |                 Priority:  normal
            Component:  undetermined  |                  Version:  6.1
             Keywords:  PNG, CICP     |               Blocked By:
             Blocking:                |  Reproduced by developer:  0
Analyzed by developer:  0             |
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 Summary of the bug:
 How to reproduce:
 {{{
 % ffmpeg -y -f rawvideo -color_primaries bt709 -color_trc bt709
 -colorspace bt709 -pix_fmt yuv422p16be -s 3840x2160 -i testcard.16 -vf
 scale=in_range=limited:out_range=limited -f image2 TestCard.png
 ffmpeg version 6.1.1
   built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)

 }}}

 Produces a PNG file with a correct cICP chunk and a gAMA chunk with a
 value of 0.510.
 However, the PNG working draft states:
 When the cICP chunk is present, decoders that recognize it SHALL ignore
 the following chunks:

     iCCP
     gAMA
     cHRM
     sRGB

 So the gAMA chunk is not required and could cause issues.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10787>
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