Since you need to do a round trip, it is probably easiest to use ghostscript to convert the pdf to postscript, then do the text filtering on the postscript with perl, and then convert the postscript back into pdf with ghostscript again.

If you have ImageMagick set up properly, you can convert it with: 

convert myfile.pdf myfile.ps

[download]
and back with: 
convert myfile.ps myfile.pdf

[download]
You can convert the pdf to xml with pdftohtml using the -xml option, but I don't know how to make the resulting xml back into pdf. Perhaps one of the perl pdf modules would be able to do most of the work.

You can also work with the pdf data directly. The format is nicely documented by Adobe. I have read and written pdf files directly with low-level perl code, but now there are modules that make this much easier.

If you want to learn more about pdf I recommend pdfzone, which includes information about both commercial and open-source tools for working with pdf.

It should work perfectly the first time! - toma

In reply to Re: Editing text in PDF file by toma
in thread Editing text in PDF file by gnum

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