Sandy McGuffog

As mentioned above, pcdtojpeg is open source. The link to the code is also above. If you believe that your approach will yield better results, then make the relevant changes and show everyone.

pcdMagic is a different product to pcdtojpeg. The giveaway is they have different names.

pcdtojpeg is completely open source. You download it right here: https://sourceforge.net/projects/pcdtojpeg/files/pcdtojpeg/

pcdtojpeg is completely open source. You donlaod it right here: https://sourceforge.net/projects/pcdtojpeg/files/pcdtojpeg/

Well, pcdtojpeg is open source. What I'd suggest is that rather than discussing your views on the theory of color science, that you modify the code, see how it works and post the results here. If it works better, I'm sure that everyone would adopt your version very quickly.

I'm sorry, but I think you confuse negative values in ICC profiles with negative values in RGB images. A negative component in the Apple Display ICC does not mean that it can display negative RGB values.

Great, I'm glad you got it sorted.

Well, what negative RGB values indicate is exactly negative stimulation of the cones, so any color with them will not exist in a real image. Photo CD images represent scans of actual media, so those colors won't exists in any real scan.