Legacy ImageMagick Discussions Archive

Hi,

I'm trying to seperate all channel from a RGB file to CMYK. I would like to use this separation to print the image to an CMYK DOD printer.

So far it works with this example below.

-ColorsCMYK.png is the reference file with the cian magenta yellow black and white.

convert tmp.tif -dither floydsteinberg -remap ColorsCMYK.png tmp2.tif

convert tmp2.tif -fill white +opaque "rgb(0,255,255)" cyan.tif
convert tmp2.tif -fill white +opaque "rgb(255,0,255)" magenta.tif
convert tmp2.tif -fill white +opaque "rgb(255,255,0)" yellow.tif
convert tmp2.tif -fill white +opaque "rgb(0,0,0)" Black.tif

convert cyan.tif -fill white -opaque black cyan.tif
convert cyan.tif -fill black -opaque cyan cyan.tif

convert magenta.tif -fill white -opaque black magenta.tif
convert magenta.tif -fill black -opaque magenta magenta.tif

convert yellow.tif -fill white -opaque black yellow.tif
convert yellow.tif -fill black -opaque yellow yellow.tif

convert Black.tif yellow.tif magenta.tif cyan.tif +append -type grayscale -depth 8 -compress none seq.tif

One problem I still have.

If I have a zone with one full color (like RED) then I do not get a raster for this zone to CMYK.
Can someone help me?

Thanks,
Jean-Luc