Paweł Jackowski
Thanh:
I am not sure what can be done with this, since it's hard to define the right behaviour of pdftex in this situation. My vote is to leave things as they are, and document relevant issues in the manual.
Taco:
I do not see how pdftex could distinguish between a user who is knowledgeable and purposely trying to achieve a special effect and a user who is naively doing something redundant. In the case of CMYK image files, the probability of dealing with an expert user is pretty high, so the current action seems fine to me.
I'm convinced in all the points. Manual updated.
Well, there is a point for "do what the naive user expects" rather than "do the least invasive thing". Of course, there should be an option for the expert to switch the behavior to the minimal thing if he needs it. The point is that the expert will be more likely to know that something "special" is called for, even if this "something special" consists in _not_ doing something. It appears to me like the files in question might certainly constitute something that might crop up in a naive user's workflow. Having them get false color is not going to be a selling point, even though there is a technical reason behind it and there _might_ be cases where the user indeed prefers the system not interfering. But those, I think, would be the special cases. That being said, I am clearly out of my depth here with regard to the technical issues involved and possible solutions, so I have to accept the expert's decisions on them. -- David Kastrup