mrpatrek / java-improved-huffman-coding

Improved (modified) Huffman coding that tries to behave as an adaptive one (this is NOT a so-called "Adaptive Huffman coding", but it would be it if this phrase hadn't already been reserved)

Improved Huffman coding

Modified Huffman coding that tries to behave as an adaptive one (this is NOT a so-called "Adaptive Huffman coding", but it would be it if this phrase hadn't already been reserved). This is something that does not exist (at least I did not find something like this except for the above-mentioned Adaptive Huffman coding that uses different technique, so it's not the same), so it was sort of an improvisation from my side.

Results

Briefly: Unlike normal Huffman coding that works well for static letter frequencies only, Improved Huffman coding works well for both static and dynamic (!) letter frequencies. Worst-case (dynamic freq.) compression ratio for normal Huffman was around 1.06, when in case with Improved Huffman the worst-case compression ratio was around 1.18, which is better than normal Huffman. Considering that a best-case (static freq.) compression ratio differed for a negligible amount when comparing both codings (around 0.01 less for Improved Huffman), I can say that the efforts for Improved Huffman coding paid off.

A bit more detailed: see THIS.