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Possible bug IM 6.9.9.49 vs 7.0.7.37 converting CMYKA PDF to CMYKA TIFF

Posted: 2018-05-30T15:37:57-07:00
by fmw42
Input (CMYK PDF):

http://www.fmwconcepts.com/misc_tests/p ... s-test.pdf

This works fine in IM 7

Code: Select all

magick -depth 8 -colorspace sRGB trans-test.pdf -alpha extract mask.png
magick \( -depth 8 -colorspace CMYK trans-test.pdf \) \
mask.png -alpha off -compose CopyOpacity -composite \
trans-test_mask7.tif
http://www.fmwconcepts.com/misc_tests/p ... _mask7.tif


But this fails in IM 6

Code: Select all

convert -depth 8 -colorspace sRGB trans-test.pdf -alpha extract mask.png
convert \( -depth 8 -colorspace CMYK trans-test.pdf \) \
mask.png -alpha off -compose CopyOpacity -composite \
trans-test_mask6.tif
http://www.fmwconcepts.com/misc_tests/p ... _mask6.tif

Same version of Ghostscript: 9.23

Mac OSX Sierra

Re: Possible bug IM 6.9.9.49 vs 7.0.7.37 converting CMYKA PDF to CMYKA TIFF

Posted: 2018-05-30T17:16:33-07:00
by magick
Per the porting guide, alpha is reversed for IMv6 and IMv7-- so negate the mask for iMv6:

Code: Select all

convert \( -depth 8 -colorspace CMYK trans-test.pdf \) \
  \( mask.png -negate \) -alpha off -compose CopyOpacity -composite \
  trans-test_mask6.tif

Re: Possible bug IM 6.9.9.49 vs 7.0.7.37 converting CMYKA PDF to CMYKA TIFF

Posted: 2018-05-30T18:30:29-07:00
by fmw42
Thanks. I forgot about that. Sorry, for the false alarm.