[Trac #499] Camera Image Very Noisy

[Zarro Boogs per Child]

#499: Camera Image Very Noisy
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 Reporter:  mfoster   |        Owner:  mfoster 
     Type:  defect    |       Status:  assigned
 Priority:  high      |    Milestone:  BTest-2 
Component:  hardware  |   Resolution:          
 Keywords:  relnote   |  
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Comment (by AlbertCahalan):

 I think this could be filtered out in software. A few ideas:

 a. For each channel (RGB is OK, but raw Bayer is better), convert to
 linear data. (gamma==1) Take an FFT. Zero out the frequencies that
 represent the lines. Do an inverse FFT. De-mosaic if not already done.
 Convert from linear to sRGB.

 b. Take three images. Choose the median for each value.

 c. Replace each pixel with the median of itself, the pixel above, and the
 pixel below. By far, it's best to do this with same-color pixels prior to
 de-mosaicing. (in that case, for green you might use the surrounding 4)

 d. For pixels that are not the median of their neighbors, interpolate.

 Remember: always operate on linear (gamma==1) data. Never do this stuff on
 sRGB data.

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Ticket URL: <http://dev.laptop.org/ticket/499#comment:11>
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