Png Rgb Transformation Related To Alpha In Getimagedata?

I have a PNG image with some pixels having an alpha of 254. These pixels have this color : RGBA{183, 221, 129, 254} (not a javascript notation). I can check in Gimp that the R, G

Solution 1:

It's almost certainly caused by gamma correction. In short, most web browsers ignore the colour-space included in the image and use the default one (as its impossible to get everything to use the colour space without a large performance penalty, especially plugins such as Flash).

Provided you don't care about really old browsers (Opera 6 and Safari 1 most notably), you can just save the image without any gamma information.