I have a large number of multi-layer PSD files which contain alpha gradients. The color behind these gradients are black. This is a simplified form of what I am using:
Code: Select all
convert -background transparent source.psd -flatten output.png
When I run this conversion, the color behind the alpha gradient becomes a strange, noisy gradient (not black), and the alpha, although it stays smooth, gets dimmer. In other words, the RBG values are not at all being preserved. Alpha is being dimmed, but not distorted as theses values are. My guess would be some sort of rounding error based on trying to extrapolate the color from the alpha as though it is trying to "unpre-multiply" the values.
Source example over grey
Converted over grey:
I used AfterEffects to do a render of RGB strait, where the alpha is ignored, and the problem is even more apparent:
Source:
Converted:
Any help is appreciated!