CMYK to RGB Conversion problem

[RickWeb]

Hi,

I have looked at the existing posts and unfortunatley they do not seem to answer my problem.

I have the following cmyk image which I need to convert to RGB. If I use the colorspace command i get the second image linked to below.

http://www.orchardtest.co.uk/imagecmyk.jpg

http://www.orchardtest.co.uk/imagergb.jpg

I have the newest version of imagemagick and have configured it with -llcms. However, whenever I use the -profile command it says it cannot find any of the profiles I choose.

Any advise is greatly appreciated as I am very stuck

Thanks
Rick

[Bonzo]

There may be an answer in Anthonys examples - http://www.imagemagick.org/Usage/

[RickWeb]

Thanks I will take a look

[RickWeb]

Unfortunatley it only suggests the -colorspace option I have already tried.

Does anyone have any more sugestions?

Thanks
Rick

[anthony]

The -colorspace operator actually effect how an image is store in IM's memory. Though only two options exists RGB and CMYK, with an optional Matte channel and 'color pallette' map. Some colorspaces transform the images so 'grey' makes all RGB channels the same.

The -type defines the style of the image read in (or sets it as it is read in). But more importantally it effect how the image is written out! It may also do some -colorspace calls, but in general effects the image format used when writing the image.

this has been added to IM Examples, Basics
http://www.imagemagick.org/Usage/basics/#type
but may take a day or two to appear on the main site.

[RickWeb]

Hi,

I have tried to do the following commands and get the same or even worse results

convert -type TrueColor cmyk.jpg rgb.jpg

convert -colorspace RGB -type TrueColor cmyk.jpg rgb.jpg

Do you have any more ideas?

Thanks
Rick

[RickWeb]

Hi,

I have just realised that it is not just this image that is now causing me problems. Any cmyk jpg or tiff I convert to rgb loses most of its coilor when using the colorspace command.

Is there anyone willing to help me out with this. I am happy to treat it as a job and pay for your time helping me configure imagemagick to work correctly.

Thanks for your time
Rick

[RickWeb]

Hi Finnally managed to solve the problem by installing all the color profiles and using the following command if anyone is interested.

convert -profile /usr/share/color/icc/Adobe\ ICC\ Profiles/CMYK\ Profiles/USWebCoatedSWOP.icc cmyk.jpg -profile /usr/share/color/icc/Adobe\ ICC\ Profiles/RGB\ Profiles/AdobeRGB1998.icc rgb.jpg";

Hope this helps someone out.

Rick