[Magick-bugs] Total ink density not preserved with JPEG compression

[Michael Timm]

When converting images from a RGB colorspace to a CMYK colorspace,
ImageMagick outputs JPEGs with pixels that are darker than the maximum
target CMYK total ink value. 
 
Since it's a product of the JPEG compression and not the colorspace
conversion, the problem is restricted to small pixel clusters. However, this
is a significant problem where the images are to be used in press-ready
artwork, where automatic pre-flight checks flag the offending images as
potential production problems.
 
The command-line used to generate the output file was:
C:\>convert "test.jpg" -profile "RGB.icc" -profile "CMYK.icc" -quality 92
-sampling-factor 1x1 "test_out.jpg" 

I can provide a sample image and ICC profiles if required.

Version: ImageMagick 6.3.4-7-Q8 (under Windows XP SP2)
  	
Michael Timm	
 	
 	
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