Address 4186 #4189
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Address 4186 #4189
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JPEG with CMYK color space need inversion of the pixel colors.
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JPEG with CMYK color space need inversion of the pixel colors.
This was an an undetected problem so far.
The fix checks whether we have extracted a JPEG image with color space CMYK, respectively number of components = 4.
If so, we convert / reprocess the image buffer specifying the option "invert_cmyk". As we cannot know the original JPEG quality, the reprocessing uses JPEG quality 95 (close to lossless).
This fix covers cases
Document.extract_image(xref)as well aspage.get_text("dict")outputs.There seems to be no way of verifying the success of this.
Note:
The MuPDF CLI tool
mutool extractalso does it wrong and extracts JPEG/CMYK images with inverted (wrong) colors.