CMYK JPEGs appear fuzzy when using subsampling

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ccampbell
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CMYK JPEGs appear fuzzy when using subsampling

Post by ccampbell »

I'm using ImageMagick to convert RGB JPEG images to CMYK for print purposes. However, some of the JPEGs are coming across blurred after the conversion. After playing around with images, I think I've narrowed it down to JPEGs that were saved with subsampling (ie, 2x2, 2x1, etc). Images that were saved without subsampling (1x1) convert just fine.

Example (good results):

Code: Select all

convert test_rgb.jpg -sampling-factor 1x1 -profile sRGB.icm -profile USWebCoatedSWOP.icc test_cmyk.jpg
Example (fuzzy results):

Code: Select all

convert test_rgb.jpg -sampling-factor 2x2 -profile sRGB.icm -profile USWebCoatedSWOP.icc test_cmyk.jpg
I am using ImageMagick 6.6.8. Is anyone aware of an issue with the CMYK JPEG coder?
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