Re:Building a data compression utility in Haskell using Huff...
by lazamar on Thursday July 04, 2024 @10:18AM
(#40875165)
Indeed, but worth noting that LZ is a modelling scheme, whilst Huffman is a coding technique.
That is, LZ determines, dynamically as it goes, what are all the elements we want to encode and their probabilities. Then you need a coder, like Huffman, to actually encode it.
In the post I used a semi-static zero-order byte-based model.
Which means I counted the byte occurrences first and just used that count for the probabilities throughout all of the encoding. Then I used Huffman codes to translate those probabilities into bits.
But I'm considering writing a follow-up changing this static model for an LZ77 one as I think that would be fun.
That is, LZ determines, dynamically as it goes, what are all the elements we want to encode and their probabilities. Then you need a coder, like Huffman, to actually encode it.
In the post I used a semi-static zero-order byte-based model. Which means I counted the byte occurrences first and just used that count for the probabilities throughout all of the encoding. Then I used Huffman codes to translate those probabilities into bits.
But I'm considering writing a follow-up changing this static model for an LZ77 one as I think that would be fun.