GhostScript's file path in ImageMagick

Question

I am attempting to use ImageMagick to convert PDFs to PNGs on PC and OSX -- but I can't actually install GhostScript on any of the computers my software will be used on.

Is there a way to bundle GhostScript in with ImageMagick, and just redirect ImageMagick's path to that package, so I can use it without officially "installing" it on the user's computer?

I found this page, but I can't understand how one might change the delegates.xml file in ImageMagick to make it work correctly. I gather that I have to change some part of this line:

  <delegate decode="pdf" encode="eps" mode="bi" command=""@PSDelegate@" -q -dQUIET -dPARANOIDSAFER -dBATCH -dNOPAUSE -dNOPROMPT -dMaxBitmap=500000000 -dEPSCrop -sDEVICE=epswrite "-sOutputFile=%o" -- "%i"" /> 

but I'm not sure what to do -- where to put the path in, or what the path should be based on --- ImageMagick's location, or something else? Any help would be super appreciated.

UPDATE v1.2: I've attempted to change the delegate above to the following, with the executable in the command line:

 <delegate decode="pdf" encode="eps" mode="bi" command="&quot;F:\ImageMagickTest\ImageMagick\gs\bin\gswin32c.exe&quot; -q -dQUIET -dPARANOIDSAFER -dBATCH -dNOPAUSE -dNOPROMPT -dMaxBitmap=500000000 -dEPSCrop -sDEVICE=epswrite &quot;-sOutputFile=%o&quot; -- &quot;%i&quot;"/>

but when I run the program, I get the following error in the cmd prompt:

Microsoft Windows XP [Version 5.1.2600]

(C) Copyright 1985-2001 Microsoft Corp.

F:\Documents and Settings\Administrator>F:\ImageMagickTest\ImageMagick\convert.e
xe F:\ImageMagickTest\PDFs\Appointment.pdf F:\ImageMagickTest\ConvertedPDFs\Appo
intment.png
convert.exe: `%s' (%d) "F:/ImageMagickTest/ImageMagick/gs9.06/bin/gswin32c.exe"
-q -dQUIET -dPARANOIDSAFER -dBATCH -dNOPAUSE -dNOPROMPT -dMaxBitmap=500000000 -d
EPSCrop -dAlignToPixels=0 -dGridFitTT=2 "-sDEVICE=pngalpha" -dTextAlphaBits=4 -d
GraphicsAlphaBits=4 "-r72x72"  "-sOutputFile=F:/DOCUME~1/ADMINI~1/LOCALS~1/Temp/
magick-5996ZNQmVN7RFumY--0000001" "-fF:/DOCUME~1/ADMINI~1/LOCALS~1/Temp/magick-5
996r7pmg8XgvrNB" "-fF:/DOCUME~1/ADMINI~1/LOCALS~1/Temp/magick-5996yhTQgwoLswnn"
@ error/utility.c/SystemCommand/1890.
convert.exe: Postscript delegate failed `F:\ImageMagickTest\PDFs\Appointment.pdf
': No such file or directory @ error/pdf.c/ReadPDFImage/679.
convert.exe: no images defined `F:\ImageMagickTest\ConvertedPDFs\Appointment.png
' @ error/convert.c/ConvertImageCommand/3044.

To me, this would seem to indicate that it's not finding the file "Appointment.pdf". But it's there. What am I not grokking?

For fun, here is the full path of gs, as taken from windows explorer:

F:\ImageMagickTest\ImageMagick\gs\bin\gswin32c.exe

For even more fun, here is the c# script that is calling it, from within a Unity 3D application (I receive no errors):

    string currDir = System.Environment.CurrentDirectory;
    string convertPath = currDir + @"\ImageMagick\convert.exe";
    string convertedDir = currDir + @"\ConvertedPDFs\";
    string pdfFolder = currDir + @"\PDFs\";
    string fileName = "Appointment";
    string argumentForImageMagick;


    argumentForImageMagick = pdfFolder + fileName + ".pdf" + " " + convertedDir + fileName + ".png";
    ProcessStartInfo info = new ProcessStartInfo {Arguments = argumentForImageMagick , FileName = convertPath};
    System.Diagnostics.Process.Start(info).WaitForInputIdle();

Answer 1

Try to replace the ""@PSDelegate" -q part of that line by "/usr/local/bin/gs -q (or whatever path you're going to install the Ghostscript executables to).

Depending on your environment, you might need to add extra parameters to that command/line which tell gs (on Windows: gswin32c.exe or gswin64c.exe) where its libraries are to be found:
-I/usr/local/share/ghostscript/9.06/lib/

---

Update: Try to run this Ghostscript command directly in a cmd.exe window to see if it works (or which errors it spawns):

"F:/ImageMagickTest/ImageMagick/gs9.06/bin/gswin32c.exe" \
   -o F:/ImageMagickTest/PDFs/test.png                   \
   -dEPSCrop                                             \
   -dAlignToPixels=0                                     \
   -dGridFitTT=2                                         \
   -sDEVICE=pngalpha                                     \
   -dTextAlphaBits=4                                     \
   -dGraphicsAlphaBits=4                                 \
   -r72                                                  \
    F:/ImageMagickTest/PDFs/Appointment.pdf

Don't worry about my usage of forward slashes ('/') as directory separators -- Ghostscript on Windows can handle these just fine.

I hope your Ghostscript installation is a recent version (otherwise it won't understand the -o syntax for the output file).

If this command doesn't work, you should see some sort of error message in the window (because I skipped the -q -dQUIET params).

Probably Ghostscript doesn't find its libraries, because you may have copied the .exe file only, and not properly installed the full package.

Maybe you need to add -I"F:/ImageMagickTest/ImageMagick/gs9.06/lib" or something similar to the commandline (I don't know were your Ghostscript /lib directory really is located -- this is just a guess!):

"F:/ImageMagickTest/ImageMagick/gs9.06/bin/gswin32c.exe" \
   -o F:/ImageMagickTest/PDFs/test.png                   \
   -I"F:/ImageMagickTest/ImageMagick/gs9.06/lib"         \
   -dEPSCrop                                             \
   -dAlignToPixels=0                                     \
   -dGridFitTT=2                                         \
   -sDEVICE=pngalpha                                     \
   -dTextAlphaBits=4                                     \
   -dGraphicsAlphaBits=4                                 \
   -r72                                                  \
    F:/ImageMagickTest/PDFs/Appointment.pdf

You should only continue with the modifying the line in delegates.xml after you succeeded to run Ghostscript directly in the cmd.exe window.

Answer 2

I had the same problem with this trying to use ImageMagick and GhostScript on a computer without administration rights (using portable versions of both). Got the error messing trying to manually set the path to GhostScript within the delegates.xml, trying to batch covert PDF files to TIFF.

The solution i found was to replace all the instances of "@PSDelegate" with the full path, like: &quot;C:\<path_to_exec>\gswin32c.exe&quot; in the delegates.xml file, and not only the PDF specific line. It worked fine after this.

This probably since GhostScript is used for other formats as well, and is perhaps dependent on other "@PSDelegate" instances within the delegates.xml file when converting a PDF file.