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Problem

Following recommendations from a variety of discussion (see below), I have attempted to use ghostscript to convert a PDF file in an sRGB colorspace (generated by Inkscape) into a PDF/X-1a file, in a CMYK colorspace.

The command I have used is the following:

gs -dBATCH -dNOPAUSE -dPDFA -sDEVICE=pdfwrite \
  -sDefaultCMYKProfile=/usr/share/color/icc/colord/SWOP_TR005_coated_5.icc \
  -sOutputICCProfile=/usr/share/color/icc/colord/SWOP_TR005_coated_5.icc \
  -sProcessColorModel=DeviceCMYK \
  -sColorConversionStrategy=CMYK \
  -sColorConversionStrategyForImages=CMYK \
  -dRenderIntent=3 -dDeviceGrayToK=true \
  -dOverrideICC -dPDFACompatibilityPolicy=1 \
  -o cmyk.pdf rgb.pdf

Some of these switches may be unnecessary. Mostly, I am ignorant of their function, but have copied them from various sources in an attempt to find some solution to the application consistently generating files with sRGB output, rather than CMYK, as desired.

The sRGB color profile in the output is confirmed by ImageMagick, as follows:

$ identify -verbose cmyk.pdf
Image: cmyk.pdf
  Format: PDF (Portable Document Format)
  Mime type: application/pdf
  Class: DirectClass
  Geometry: 72x72+0+0
  Resolution: 72x72
  Print size: 1x1
  Units: Undefined
  Colorspace: sRGB
  Type: PaletteAlpha
  Base type: Undefined
  Endianess: Undefined
  Depth: 16/8-bit
<full content truncated>

Note that ghostcript is version 9.50, and is running under Linux Mint 20.0.

What might be a better usage of the application, to produce CMYK output?

References

brainchild
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  • Were you able to fix it? – Adrian Lopez Feb 24 '22 at 06:50
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    @Adrian: No, I never found a solution. – brainchild Feb 24 '22 at 08:22
  • Some people are telling me that the issue might be in identify instead of gs. Which make sense because the color conversion is happening, I can see visually. – Adrian Lopez Feb 24 '22 at 18:35
  • @Adrian: Might you clarify, please, what you have done? It seems you have reproduced my procedure, creating a target document that you visually identify as CMYK even though it is reported by the tool as sRGB? – brainchild Feb 25 '22 at 03:26
  • Yes. Pretty much your procedure: https://pastebin.com/yib3kc3p – Adrian Lopez Feb 25 '22 at 03:36
  • @Adrian: I am not too familiar with the tools, one of the reasons for posting the question. I wonder whether there is an objective way to verify an inaccuracy with the output of `identify`. Are you reasonably confident your subjective observation is reliable? I imagine your display device is sRBG, which I would understand would not reliably display the output colors. – brainchild Feb 25 '22 at 03:42

0 Answers0