[FFmpeg-trac] #3345(swscale:open): Bias in planar YUV to YUV bit depth conversion

[FFmpeg]

#3345: Bias in planar YUV to YUV bit depth conversion
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             Reporter:  abc123      |                    Owner:  (none)
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  swscale
              Version:  git-master  |               Resolution:
             Keywords:  bounty      |               Blocked By:
             Blocking:              |  Reproduced by developer:  0
Analyzed by developer:  0           |
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Comment (by pdr0):

 Replying to [comment:14 pdr0]:
 > Replying to [comment:13 Balling]:
 > > Are results worse with dither?

 >
 > Yes, results are worse with dither.


 To clarify, I mean "worse" in the sense that it adds another variable. On
 that solid color, some values increase using swscale to the correct value
 because of the dithering "noise" added - it's actually "better" in that
 sense because of 100% wrong, it's some % right. Or if you look at zscale,
 instead of being 100% right, it adds some % wrong when you add dither. The
 underlying problem for this ticket should be a math issue somewhere
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/3345#comment:15>
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