ONE to ONE compress

This site discusses a characteristic of some compression algorithms that the author refers to as One to One (bijective) compression. In a nutshell, this property means that for any file X, F( F'( X ) ) == X. (F is either the compressor or decompressor, and F' is its opposite number.) This is definitely not the case for most conventional compression algorithms.

This page has a some Huffman compression code that has been adapted to implement a bijective property.