A parallel decoder for LZ2 compression using the ID update heuristic

The LZ2 compression method seems hardly parallelizable since some related heuristics are known to be P-complete. In spite of such negative result, the decoding process can be parallelized efficiently for the next character heuristic. We show an other parallel decoding algorithm for LZ2 compression using the ID update heuristic. The algorithm works in O(log/sup 2/n) time with O(n/log(n)) processors on a PRAM EREW, where n is the length of the output string.