Hi folks,

This is my first Perlmonks question. Hope I'm in the right place.

I've got a large corpus of documents and I'm trying to write a script that will find all the documents containing black redaction rectangles. Example:

http://www.limathreefive.com/pdf/GBA.pdf

I've spent a couple of days playing around with CAM::PDF, and I've managed to detect some rectangles by using PDF::CAM's parsing code (using CAM::PDF::Renderer::Text as a model) and then looking for and interpreting relevant PDF operators (re, m, l, f, etc). This works OK, but it doesn't detect all the relevant rectangles (like the ones in the files above), and it involves me writing a lot of low-level code. I'm sure there are subtleties in the PDF spec I'm not taking into account, and that this will cause me to miss some files.

So: are there other libraries I should be using? I've looked at the API2 documentation and it doesn't appear to handle this sort of thing better than CAM does. Or does CAM have other helpful (ideally higher-level) functions I ought to be using?

Thanks!

-Tim

In reply to Finding Rectangles in PDFs by binarybits

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