How Do I Compress A 500 Kb PDF File To Less Than 100 Kb Without?

How Do I Compress A 500 Kb PDF File To Less Than 100 Kb Without?

I rarely compress PDF files for emailing or any other purpose. For emailing, I very occasionally apply 7-Zip, not so much for its superior compression, but instead for its AES-256 encryption. 7-Zip - Wikipedia One reason that I do not generally recommend applying compression to PDF files is that much of their included information is already compressed. For example, images within PDFs are typically already encoded. PDF - Wikipedia Other information (e.g. vector graphics and text) are also typically somewhat compressed. PDF supports dictionaries for replacing redundant chunks of information with pointers to their dictionary definitions. A more generally efficient PDF compression would involve first unraveling them and applying compressions optimized for each element. For example, compressing text string information (e.g. Huffman coding - Wikipedia), then including a decompression dictionary along with formatting rules for rendering that recovered textual information during PDF playback.