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I have noticed a severe problem with ghostscript. A bug report was filed |
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with the ghostscript upstream maintainers, but, surprisingly (to me at least) |
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no one could reproduce the problem. This may indicate that the problem is |
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unique to Gentoo ghostscript or that something strange is happening in my |
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system. What I need is verification from other Gentoo users. |
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|
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The problem concerns the ghostscript raster drivers such as PGM, TIFF, PNG, |
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etc. Whenever a certain resolution (the exact value depends on the driver) |
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is exceeded, the output for any embedded images in the PostScript file is all |
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black. Text is rendered without problem, but if an image is inserted into |
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the document, say with OpenOffice, the image is rendered all black (above certain |
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resolutions). |
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|
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Why do I use these raster drivers? |
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|
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There can be a need to use them on occasion, but, more significantly, I print |
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documents with the ghostscript IJS driver from Hewlett-Packard. Ghostscript must |
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supply some kind of raster to the IJS driver because any embedded images are printed |
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all black. The problem therefore probably extends beyond the raster drivers |
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themselves. |
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|
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Attached is a sample PostScript file, image-test.ps. With a PostScript viewer |
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such as gv or gsview, the image is clearly visible. If some Gentoo user could |
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render this file into a PGM format using the following command and then report the |
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results, it would be very helpful to me. |
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|
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gs -dSAFER -dBATCH -dNOPAUSE -sDEVICE=pgm -r380 -sOutputFile=image-test.pgm image.ps |
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|
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Viewing the resulting image file with an image viewer such as display from ImageMagick |
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(display -resize 25% image-test.pgm) should show an all white page with an all black |
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rectangle in place of the central image. |
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|
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Interestingly, if the resolution in the above command is changed to 300dpi (-r300) |
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the raster driver renders the image correctly. I found the exact cut-off value |
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to be 326. |
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|
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The same behavior applies to the TIFF and PNG drivers although at different |
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cut-off resolution values for each driver. However, the fax drivers, tiffg3, |
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and the pbm driver seem unaffected. |
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|
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If someone can verify this problem, then Gentoo ghostscript must be the fault. |
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If no one else can reproduce the issue then I am somehow in possession of a |
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jinxed system (although the same problem exists on both of my Gentoo machines). |
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|
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Frank Peters |