Remove common PDF watermarks

Branches

Each branch is a variation of the script, customized to remove a particular common PDF watermark.

• "pdf-xchange-editor"
  • generic methodology
  • removes all objects with an element containing the labels: /Private /Watermark
  • supports the command-line option: --unzip
  • filters are also applied to the zlib compressed data within "FlateDecode" streams
• "www.finebook.ir"
• "www.it-ebooks.info"
• "www.wowebook.org"
• "www.wowebook.org" with zlib compressed data within "FlateDecode" streams
• "www.allitebooks.com" with zlib compressed data within "FlateDecode" streams

Notes

• These are perl scripts.
• To run: perl filter.pl
• These implementations don't accept any command-line options. They assume that:
  • the input file is: ./in.pdf
  • the output file is: ./out.pdf

Additional Notes

• After running a PDF file through the appropriate perl script:

  • a PDF viewer (ex: "PDF-XChange Viewer") should report that:

  This document "out.pdf" has errors.
  
  Some problems were detected by application:
  - One or more XREF chunks were not found.
  
  It is recommended you re-save this document.

• After following the recommendation given by the viewer and resaving the PDF document (ie: File > Save As..):
  • all of the PDF's internal references to the removed obj blocks are cleaned out
  • the file size is farther reduce by a significant amount
  • the file won't generate any errors when opened in a PDF viewer

Legal

• Copyright: Warren Bank
• License: GPL-2.0