good library for pdf

[Steve Holden]

Enrique Palomo Jiménez wrote:
> Hi all,
> 
> I want to take an existing pdf and add it a non-opaque watermark.
> I have tried it in postscript but postscript hava an opaque imaging model.
> Pdf allows it. I can do it with acrobat 6.0, but i need to add the watermark in batch mode or inside an application.
> 
> I've found lowagie library for java.
> 
> Anyone knows if there is something similar for python??
> 
> must i begin to learn java?? 
> 
> Regards

For what it's worth, if you use PostScript correctly there will be no 
need to migrate to PDF (though it can have advantages).

PostScript doesn't "have an opaque imaging model" at all. You can define 
arbitrary paths, and draw on top of existing graphics. Problems may 
occur if you want your watermark to appear "behind" your main content if 
the main content draws with an opaque background (because that would 
obscure the watermark and render it invisible), but that's nothing to do 
with PostScript per se, so you might be trying to walk a hundred miles 
when a trip round the corner would do.

The ReportLab functionality (PageCatcher) to read existing PDFs and 
incorporate them as a part of other PDF documents is not, unfortunately, 
a part of the open source toolkit.

regards
  Steve
-- 
Steve Holden       +44 150 684 7255  +1 800 494 3119
Holden Web LLC                     www.holdenweb.com
PyCon TX 2006                  www.python.org/pycon/