Ghostscript (or Postscript?) error

denydias · 12-13-2014, 08:01 AM

Hi all,

I'm working on a project where I need to programmatically convert a lot of PDF files to TIFF. A fast and reliable tool for this is Ghostscript. But I'm facing troubles with it.

Here is the command line I'm using for the job:

Code:

$ gs -q -dSAFER -dBATCH -dNOPAUSE -r300x300 -sDEVICE=tifflzw -sOutputFile=out-%06d.tif inputfile.pdf

As one can see, I'm converting a PDF file to TIFF with an output resolution of 300dpi, 1bit color (B&W) and LZW compression. This is a requirement for the project.

When I run the above line on Slackware, I get this:

Code:

Unrecoverable error: undefined in .getdeviceparams
Operand stack:
    --nostringval--  --nostringval--

Now, when I run it under Ubuntu (>12.04) it work just fine. It also works on Slackware when I change the device to -sDEVICE=tiffgray, but this gives me an 8bit color file, which breaks the project specification.

I've already look around the net and can't find anything that help me to solve this out. That's why I'm asking for the Slackware experts here.

Does anyone out there have faced something similar? Is this a Ghostscript or Postscript error? Is there any know solution for this under Slackware?

Bellow are some debug info about GS. The Slackware it's running on is a -current multilib.

Code:

$ gs
GPL Ghostscript 9.07 (2013-02-14)
Copyright (C) 2012 Artifex Software, Inc.  All rights reserved.
This software comes with NO WARRANTY: see the file PUBLIC for details.
GS>devicenames ==
[... /tifflzw ...]

Let me know if I can provide any piece of information from this system.

I thank you very much in advance for any relevant information.

dwblas · 12-13-2014, 12:27 PM

Don't know what you have or have not looked at, or if you are converting images that are originally color or black and white, but Imagemagick/convert is the usual way to convert images. It seems, to me at least, that you will have to set the parameters yourself as far as what is black and what is white, as you can not expect a default value to know what you want. Start with the -threshold option and see if that works for you. You may have to go through pages of Imagemagick docs to get it to do what you want but I don't see an alternative.

mancha · 12-13-2014, 01:18 PM

Quote:

Originally Posted by denydias

Is this a Ghostscript or Postscript error? Is there any know solution for this under Slackware?

Hi.

I reproduced on my 14.1 system. Turns out to be a bug in Ghostscript (missing initializers in tifflzw & tiffpack).

Solution: Re-build Ghostscript 9.07 after applying: ghostscript-9.07_tifflzw_pack.diff

--mancha

denydias · 12-15-2014, 10:57 PM

Quote:

Originally Posted by dwblas

Imagemagick/convert is the usual way to convert images.

Indeed. But PDF is a language and Ghostscript has a much better performance over ImageMagick for this particular task. gs is almost 7x quicker and takes less than a half of the memory usage when compared to convert. In a large scale application, this is serious figures.

Quote:

Originally Posted by mancha

I reproduced on my 14.1 system. Turns out to be a bug in Ghostscript (missing initializers in tifflzw & tiffpack).

Solution: Re-build Ghostscript 9.07 after applying: ghostscript-9.07_tifflzw_pack.diff

Thank you for the test and confirm the bug, mancha! I gave a try on your diff and it indeed work.

At the end I'm going to use another device, tiffg4. This one works out without a glitch with the standard packages (ghostscript-9.07-x86_64-2 and libtiff-3.9.7-x86_64-1).