Patent · US Expired

Data compression apparatus and method using matching string searching and Huffman encoding

US5532694A · kind A · utility

146Cited by
78References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 7, 1995
Grant dateJul 2, 1996
Priority date
Expiry dateJul 7, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M7/46
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method for converting an input data character stream into a variable length encoded data stream in a data compression system. A sliding window data compression algorithm is combined with Huffman encoding on the strings and raw bytes. The Huffman table, in a compressed form, is prepended to the encoded output data. The Huffman codes representing the shortest strings encode both the string length and part of the string offset. Assigning Huffman codes to represent the combined length and offset allows the use of a smaller sliding window size without sacrificing compression ratio. The smaller window size allows implementations in software and hardware to minimize memory usage, thus reducing cost.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.