Automata on Lempel-ziv Compressed Strings

Using the Lempel-Ziv-78 compression algorithm to compress a string yields a dictionary of substrings, i.e. an edge-labelled tree with an order-compatible enumeration, here called an LZ-trie. Queries about strings translate to queries about LZ-tries and hence can in principle be answered without decompression. We compare notions of automata accepting LZ-tries and consider the relation between acceptable and MSOdefinable classes of LZ-tries. It turns out that regular properties of strings can be checked efficiently on compressed strings by LZ-trie automata.

• Type: Conference
• Year: 2003
• Where: CSL
• Authors: Hans Leiß, Michel de Rougemont
• Keywords: Automata Accepting Lz-tries, Compression Algorithm, CSL 2003, Order-compatible Enumeration