7

I print marketing regularly at my job, and everything is sent to us as PDFs. The problem is, the color profile is always set to RGB, and the resulting prints look terrible and don't match the colors of prints sent to us. If I convert the PDF to CMYK, it prints perfectly. The problem is, I can't use Photoshop at work (they won't pay for a license for somene in my position).

Can anyone recommend a free or open-source application that will allow me to convert RGB to CMYK in a PDF?

3
  • You errr.. can't use Photoshop even if you had a subscription. Almost all PDFs are rasterized when you open them with Photoshop. Have you looked at any of these?
    – Scott
    Sep 8, 2014 at 1:41
  • I don't care about preserving text or anything. I already know I can import the PDFs into Photoshop, change the color profile, and print it, and the colors look fine. I've tried some other PDF editors, but none of them seem to support converting the color profile of the actual document.
    – CXL
    Sep 8, 2014 at 2:53
  • Because Photoshop is rasterizing the PDF making it an image, thus allowing you to change the color profile of the image not the actual PDF. Look for something which will rasterize a PDF to an image.
    – Scott
    Sep 8, 2014 at 2:56

2 Answers 2

5

Use ghostscript, its the most obvious OSS tool for the job. Here's a sample for windows usage from stackoverflow [1]:

gswin32.exe ^
    -o c:/path/to/output-cmyk.pdf ^
    -sDEVICE=pdfwrite ^
    -dUseCIEColor ^
    -sProcessColorModel=DeviceCMYK ^
    -sColorConversionStrategy=CMYK ^
    -sColorConversionStrategyForImages=CMYK ^
     input-rgb.pdf

Tested and worked fine for 3 of my test PDF's. There are other ways to do color conversion to be more specifically what you want but this is probably enough for you, as for software selection.

Ghostscript is a quite complex application capable of very many things provided that you do the proper research. So it can do other things like add watermarks, translate pages etc. You probably need -sOutputICCProle = my device prole.icc[2].

References:

  1. Script (or some other means) to convert RGB to CMYK in PDF?, 2012. Stackoverflow.

  2. Ghostscript 9.07 Color Management

2
  • Please note -o is duplicated in the command example above. Should be only one. Aug 23, 2020 at 22:52
  • @alexandroid fixed thanks
    – joojaa
    Aug 24, 2020 at 5:12
4

The already mentioned ghostscript is the free standard tool for this problem. If the use of the command line looks too daunting, you could use a free web service like: http://www.pdf2cmyk.com. You won't have any control whats really happening with your images, but the results are good as far as I tested. You can choose different output profiles (SWOP and ISO).

0

Not the answer you're looking for? Browse other questions tagged or ask your own question.