This question could be [mis]taken several ways, but. A number of tools exist, but none that I recommend. pdf compressor - Google Search Typically, PDF is not a particularly compact representation, although a patient expert can craft amazingly compact PDFs for some pages. In general, one could try rendering a PDF, then apply a battery of compressions to that output, selecting the most successful,
For some, however, this may be impractical, because a lot of files must be extracted from those PDFs. PDF output as ASCII text? The best option is a “binary to ASCII converter” -- a system that, rather than converting the output to machine code, converts it directly to characters to be recognized by various ASCII reader tools. This approach is extremely laborious, both because we have to transform a huge source to characters, and because the conversion process itself is a massive undertaking. For example, here's what the conversion process does: (Para-code converted into characters via (Para-code.py) for Python 2.6) It's pretty slow, too, and a full-text search will be more useful than a binary search.