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schnaader / fairytale

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GNU Lesser General Public License v3.0
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Recompression: Deflate #2

Open M-Gonzalo opened 6 years ago

M-Gonzalo commented 6 years ago

Currently, a plethora of media formats are compressed with a legacy algorithm from about 20 years ago. Those media formats include, among many others, legacy .zip archives, PDF documents, all files saved by Microsoft Office and LibreOffice suites, PNG images, Java .jar applications, android .apk apps and even hard drive images. There are working methods for losslessly undoing said compression in order to apply stronger algorithms to the original data. The most popular implementation of deflate comes in the form of zlib library, and Precomp is an open source implementation of such method of recompression. Even so, deflate streams aren't produced only by zlib library, but by other programs too and those aren't always recognized by precomp.

Fairytale should in due time be capable of doing recompression of most if not all deflate implementations.

M-Gonzalo commented 5 years ago

Currently, the reflate project provides a very practical way of dealing with all deflated data. It is successfully integrated into precomp and works like a charm, so maybe this is the way to go here too...