Gamma Factored Computation Option

[BeauRX]

I would like an option like PS (Blend RGB colors using gamma). 

I ran across the video Computer Color is Broken (https://www.youtube.com/watch?v=LKnqECcg6Gw) which demonstrated the effect of not factoring gamma into operations. It also showed the PS option (Blend RGB colors using gamma) to address this issue. I don’t have PS to test the option myself, maybe someone else can contribute.

I do not know the inner workings of APh, but a simple test (attached) with the Gaussian filter exhibits the same dark band issue for adjacent colors (top half). Adding a Procedural Texture filter before the Gaussian to square the color-values and one after the blur taking the square-root of the color-values appears to eliminate the dark band and yields a more pleasing transition (bottom half). Thx

GammaBlurTest.afphoto

[kirk23]

APhoto does it correct way in  rgb/32  mode   but  it should be fixed for any bit  depth  for sure.   

[Old Bruce]

Thanks for pointing that out about 32bit mode. I rarely use it so would never have found it on my own.

[BeauRX]

I believe the 32bit space is linear hence does not need the additional steps for computations.