# Converting CMYK to RGB using \*magick **URL:** \ **Category:** Rails\ **Created:** [April 11, 2008, 1:17am UTC](https://www.ruby-forum.com/t/converting-cmyk-to-rgb-using-magick/134458 "2008-04-11T01:17:25Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![jfaulkenberry](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/c2a13f/32.png) [@jfaulkenberry](https://www.ruby-forum.com/u/jfaulkenberry)\ **Post date:** [April 11, 2008, 1:17am UTC](https://www.ruby-forum.com/t/converting-cmyk-to-rgb-using-magick/134458/1 "2008-04-11T01:17:25Z")
Hi, Does anyone have any experience converting CMYK images to RGB/web using rmagick/mini\_magick/imagemagick? I’m finding that the resulting RGB images look completely different, they seem to have a green tinge… fyi, I’m converting using -colorspace RGB, and I’m using imagemagick directly because the other 2 options seem really slow (by a factor of 20 or so). I have looked into color profiles, but after trying a few via command line I noticed that I can’t use the same profiles for all of the files. Is there any good documentation out there about color profiles? or is it a bit hit and miss. I’m a bit of a beginner at this image processing stuff so I might need a bit of explanation 😉 ---
**Author:** ![jfaulkenberry](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/c2a13f/32.png) [@jfaulkenberry](https://www.ruby-forum.com/u/jfaulkenberry)\ **Post date:** [April 11, 2008, 6:15am UTC](https://www.ruby-forum.com/t/converting-cmyk-to-rgb-using-magick/134458/2 "2008-04-11T06:15:08Z")
Jonathan F. wrote: > Hi, Does anyone have any experience converting CMYK images to RGB/web > using rmagick/mini\_magick/imagemagick? > > I’m finding that the resulting RGB images look completely different, > they seem to have a green tinge… > > fyi, I’m converting using -colorspace RGB, and I’m using imagemagick > directly because the other 2 options seem really slow (by a factor of > 20 or so). > > I have looked into color profiles, but after trying a few via command > line I noticed that I can’t use the same profiles for all of the > files. Is there any good documentation out there about color profiles? > or is it a bit hit and miss. > > I’m a bit of a beginner at this image processing stuff so I might need > a bit of explanation 😉 I recommend asking on a rmagick / imagemagick mailing list. This stuff is not straightforward. Stephan ---
**Author:** ![jfaulkenberry](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/c2a13f/32.png) [@jfaulkenberry](https://www.ruby-forum.com/u/jfaulkenberry)\ **Post date:** [April 11, 2008, 6:24am UTC](https://www.ruby-forum.com/t/converting-cmyk-to-rgb-using-magick/134458/3 "2008-04-11T06:24:25Z")
Yeah you make a good point 😉 I was kinda just putting feelers out everywhere looking for anyone who had been through what I’m going through and could give me some pointers! Having said that, I have partially solved my problem! I wasn’t having any luck with profiles because I didn’t have a package installed called lcms or “Little cms”. Imagemagick uses this to convert things via color profiles 🙂 fyi, if anyone is having trouble with this (on a mac) then you should install imagemagick via the following command: sudo port install imagemagick +lcms I haven’t tried it on ubuntu yet but it’s bound to be similar Thanks, Jonzo. On Fri, Apr 11, 2008 at 4:15 PM, Stephan W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > 20 or so). > > This stuff is not straightforward. > > ## Stephan > > Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/). > > > – Jonathan