Removing false colors

[Kim Brandstetter]

I encountered this problem when my video recording device got warmer(see attachment).

Sometimes it is green.

How could I fill all areas that have that same colored violet or green with a gradient between two right colors(the way logoaway solutions do it) or some other method that recreates the original image?

[foxyshadis]

Heh, I was given a webcam recently that did the exact same thing. You can find the areas by masking off areas where the chroma is 0 or 255 (magenta is all max U & V, green is all zero U & V).

You can mask off those areas with this mask:
mt_lut("x 16 < 255 x 235 > 255 0 ?",chroma="process") # MaskTools2
mt_logic(UtoY,VtoY,"max",chroma="128")
Then apply whatever you want to fix the chroma channels.

Do you have a sample you can upload so we can test out some techniques?

[Gavino]

mt_lut("x 16 < 255 x 235 > 255 0 ?",chroma="process") # MaskTools2
There should be two ?'s at the end of the expression (since two conditional tests).
Also, upper limit for chroma should probably be 240, not 235.
mt_lut("x 16 < 255 x 240 > 255 0 ? ?",chroma="process")

[Kim Brandstetter]

Do you have a sample you can upload so we can test out some techniques?
Sure: https://www.mediafire.com/?d32x0a2o321asf0

[Kim Brandstetter]

Heh, I was given a webcam recently that did the exact same thing. You can find the areas by masking off areas where the chroma is 0 or 255 (magenta is all max U & V, green is all zero U & V).

You can mask off those areas with this mask:
mt_lut("x 16 < 255 x 235 > 255 0 ?",chroma="process") # MaskTools2
mt_logic(UtoY,VtoY,"max",chroma="128")
Then apply whatever you want to fix the chroma channels.

Do you have a sample you can upload so we can test out some techniques?

Having masked it, how do I create the gradient? Or can it be retranslated, so correct colors were captured but wrongly stored.

[Kim Brandstetter]

Any news regarding this? I still have this problem and your solution does not work :(