[FFmpeg-trac] #9751(swscale:new): Incorrect YUV->RGB24 conversion results on IBM Power9

[FFmpeg]

#9751: Incorrect YUV->RGB24 conversion results on IBM Power9
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             Reporter:  gciaparrone  |                    Owner:  (none)
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  swscale
              Version:  git-master   |               Resolution:
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Comment (by gciaparrone):

 Replying to [comment:2 Balling]:
 > When you convert ffmpeg -i black.png -pix_fmt yuv420p black.yuv you get
 limited range data with Y set to 16 and Cb, Cb achromatic (128 for 8 bit,
 12 bit per pixel yuv420p). Please attach that yuv file for IBM Power9.
 >
 > When you convert back you are IMHO supposed to set input range and
 because it is somehow gbr use accurate_rnd.
 >
 > ffmpeg -s:v 64x64 -pix_fmt yuv420p -i black.yuv -frames:v 1 -vf
 scale=in_range=tv:flags=accurate_rnd,format=rgb24 reblack1.png
 >
 > Please test.

 Hi, even with the settings you provided I got the wrong pixels on IBM
 Power9. Please see the picture attached next. Anyway, shouldn't running
 the exact same command on two different CPUs produce approximately the
 same result?
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Ticket URL: <https://trac.ffmpeg.org/ticket/9751#comment:3>
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