Andrew Coppin wrote:
apfelmus wrote:
Am I missing something or why wouldn't
encode, decode :: String -> String encode = encodeRLE . encodeHuffman decode = decodeHuffman . decodeRLE
do the job? This is probably what Andrew intends to do in his Java version. Note that this not only RLE-encodes the Huffman table but also (needlessly) the data stream. In case you only want to RLE the table, a simple Word32 field tracking the size of the Huffman table should be enough.
It is enough. But given that the whole purpose of compression algorithms is to squeeze data into the tiniest possible space, I wanted to avoid having a size field. And mathematically it's perfectly possible to do... I just can't find a convinient way to do it in Haskell. :-(
Well, those 4 bytes won't kill you. But you can of course stop RLE-decoding as soon as this has read as many bytes as there are in the Huffman table. A systematic way to do this are parser combinators. Regards, apfelmus