Can't seem to use -black-point-compensation

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
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magick
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Post by magick » 2006-10-12T13:33:43-07:00

For proper conversion of RGB to CMYK you need two color profiles: typically sRGB and a SWOP:
  • convert image.jpg -profile sRGB.icc -profile SWOP.icm image.tif

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Post by magick » 2006-10-13T10:42:40-07:00

The conversion only occurs if you have the LCMS delegate library. Type
  • identify -list configure
and ensure -llcms is part of the LIBS value.

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Post by magick » 2006-10-13T12:59:40-07:00

To properly convert CMYK to RGB or RGB to CMYK you need proper color profiles which in turn requires that ImageMagick be built with LCMS. When you configure ImageMagick from source check the last few lines of the output to ensure LCMS was found. If not, check config.log for the reason why LCMS failed to validate. ImageMagick does have a built-in conversion for CMYK to RGB and back but it a linear algorithm and does not produce very good results.

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