Magick++ Convert JPEG from CMYK to RGB Colorspace

I use the ImageMagick Magick++ API to work with images in my C++ program. It reads images out of PDF files. There are some Images that have a CMYK colorspace. How can I convert such images to RGB correctly?

Thanks 开发者_如何学运维for your help!

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I solved it now. I used the image->channel(AllChannels) method. The colors are not exactly the same as before, but it use usable.