Please someone, RGB to CMYK conversion help needed

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mortuk

Please someone, RGB to CMYK conversion help needed

Post by mortuk » 2007-07-16T07:46:39-07:00

Hey all

Firstly total n00b to Image Magick.

I have made a system for a client which enables their dealers to make bespoke adverts with their dealership info on them. It also has a logo. The problem I am having is when it generates it all into a PDF, the logo comes out in RGB instead of CMYK.

Even if I use a CMYK logo, it will still come up as RGB in the PDF. Pretty sure this is because PHP alters the image.

What command do I need to run to convert the image to CMYK so it will print out correctly in the PDF?

Cheers

mortuk

Re: Please someone, RGB to CMYK conversion help needed

Post by mortuk » 2007-07-16T09:15:54-07:00

Anyone?

Figured out something like this

convert upload/img_ad.jpg -profile CMYK_PROFILE upload/img_ad2.jpg

but dont have a valid icc or icm file that will work, I am a web dev and know nothing of colour profiles etc :P

please anyone?
Last edited by mortuk on 2007-07-17T01:38:48-07:00, edited 1 time in total.

mortuk

Re: Please someone, RGB to CMYK conversion help needed

Post by mortuk » 2007-07-17T01:13:19-07:00

come on someone this cant b hard, i just hhave no idea due to the colour proifiles, anyone help me out?

mortuk

Re: Please someone, RGB to CMYK conversion help needed

Post by mortuk » 2007-07-20T02:26:41-07:00

bump ^

pretty urgently need an answer, please can ANYONE help? I know its possible i just dont know what I am doing wrong

brian_jackson

Re: Please someone, RGB to CMYK conversion help needed

Post by brian_jackson » 2007-07-25T09:41:45-07:00

I've got the AdobeICCProfiles-2.0-31 rpm installed which provides quite a few ICC profiles.

convert rgb_file.jpg -profile path/to/srgb.icm -profile path/to/cmyk.icc cmyk_file.jpg

You can also use the utilities from the liblcms package as well. "jpegicc" and "icctrans" come to mind. http://www.littlecms.com

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