PDF to JPEG conversion using Ghostscript

Question

I'm using Ghostscript to convert my PDF files to JPEGs with Ghostscript which works great.

For my output images I'm using %03d in the file name, so the file names come out 001, 002 ... and so on according to the page numbers.

But i want in some case the numbers to start from an higher number.

For example I process a file with two pages so the output images are page001.jpg, page002.jpg

Now I want to process another PDF and instead of replacing those files, I want to create page003.jpg, page004.jpg.

How can this be done?

This is my full command line I'm using now:

'C:\gs\gs9.14\bin \gswin64c -dNOPAUSE -sDEVICE=png16m \
  -sOutputFile=page-%03d.jpg -r100x100 -q' . $pdf_file. '-c quit'

Answer 1

Here is a workaround trick, that you could use:

gswin64c.exe                  ^
   -sDEVICE=png16m            ^
   -sOutputFile=page-%03d.jpg ^
   -r100x100                  ^
   -c "showpage showpage"     ^
   -f filename.pdf

The -c "showpage showpage" inserts two empty pages into the output. The output files will be named

page-001.jpg + page-002.jpg + page-003.jpg + page-004.jpg

So the first two are white-only JPEGs and should be deleted afterwards.

You can extend this command with any number of empty pages you want.

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Update

Of course, if you know in advance that you want to convert several different PDF files to images where you want the counting for a new PDF to continue exactly from where the last PDF ended, you could do this:

gswin64c.exe                  ^
   -sDEVICE=jpeg              ^
   -sOutputFile=page-%03d.jpg ^
   -r100x100                  ^
   -f file1.pdf               ^
   -f file2.pdf               ^
   -f file3.pdf               ^
   -f [...]

---

_{BTW, your original command requests .jpg file suffixes, while the Ghostscript device is png16m. This doesn't match. Initially I blindly copied your command, but now I've corrected it.}

Answer 2

You cannot do that with the standard version of Ghostscript, the output file numbers are given as the emitted page number (so if you had a 10 page file, with /NumCOpies 2, you would get files numbered 0 to 19).

Of course, you can process the two files on the same command line, I think that will give you the second file with page numbers beginning where the first set left off.

Otherwise you will have to modify the source code of the Ghostscript device.