Creating direct/spot color images

[aleray]

Hi,

I have a bunch of grayscale images I want to convert into 1 spot color images (in eps format I guess). This images will be used in DTP software Scribus in order to create a pdf document that is not in CYMK but using spot colors too (from the Pantone library). So it is not only a question of how the image looks but rather of ink separation.

I've been searching for some way to do this with IM without success. Is there any way (alternatively using some other free/libre software)?

Thanks in advance,

Alex

[fmw42]

I am no expert on this, but I am unaware of IM being able to deal directly with Pantone colors, which I thought were CMYK anyway.

Do you have a conversion from Pantone colors to either RGB or CMYK or know where that might be available?

IM can convert from grayscale to any RGB, CMYK, HSL or HSB color using a number of techniques. See colors defined at: http://www.imagemagick.org/script/color.php

From http://en.wikipedia.org/wiki/Pantone:

"However, most of the Pantone system's 1,114 spot colors cannot be simulated with CMYK but with 13 base pigments (15 including white and black) mixed in specified amounts."

see also http://www.linux.com/archive/articles/49236

[aleray]

Hi and thanks for your reply.

The Pantone system is not based on the CMYK color seperation indeed. Color libraries in software such as Adobe In Design (Scribus doesn't include it by default because of Pantone claiming copyright, although it is widely aknowledged that color can not be copyrighted) have some sense of how to simulate those spot colors on screen using rvb/cmyk values.

Yesterday I read about deviceN, which is a specification for postscript 3 making possible to represent those spot colors (in eps for instance). I guess this would be the way to go...

http://partners.adobe.com/public/develo ... _Color.pdf

Someone just gave me a python script to make trully bichromic images (black + another color), from 2 grayscale images. It seems to make the deal (by using a fully white image as the "black" input). Here is the code:

http://pastie.org/2037293

Given the above information, do you think it would be possible to do so with imagemagick?

Thanks

[fmw42]

Unfortunately, I am not a coder (just scripter) and don't follow either reference. One of the IM developers would need to review these and answer your questions. I suppose they could be implemented, but I am not sure of the developers time availability nor priority at the moment.