I need a fast PDF Compression library for .NET that will allow me to run 10 concurrent threads each compressing a separate PDF file to around 10% of its original size. Any suggestions? (I have already tried out the product from neeviaPDF.com. It is not as fast as I need.)
+2
A:
The company's website shows three examples - one compresses a pdf from 9.1mb to 133kb. Opening them up with Notepad shows a single 2500x3000 mostly black image compressed with FlateDecode converted to the same size image compressed with JPEG2000. This kind of compression ratio is probably the best-case scenario. The other two examples are more reasonable; 741kb to 349kb and 940kb to 804kb. They also include a screenshot of the settings; one checked in all three examples contains a warning: "VERY SLOW!!!" Seems like a good product, though. It does all the right things, including web optimization.
10% of the original is unlikely unless your pdfs' contents are known ahead of time, heavy in images, and you handcode a solution using iTextSharp to take advantage of the way the pdfs are put together.
If you like the way the component you have works, and it is not thread safe, why not just create 10 separate processes with it? If you've got a lot of large images, be careful of out-of-memory errors.
R Ubben
2009-08-04 16:08:12