Patent · US Expired

Variable-length encoding using code swapping

US5991451A · kind A · utility

31Cited by
1References
48Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1996
Grant dateNov 23, 1999
Priority date
Expiry dateFeb 28, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N19/91
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The efficiency of variable-length (VL) encoding data using a defined VL encoding table is characterized and one or more changes to one or more entries of the defined VL encoding table are determined that increase the efficiency of encoding the data. An updated VL encoding table is generated from the defined VL encoding table based on the changes. VL codes for the data are generated using the updated VL encoding table, and an encoded bitstream is generated from VL codes, wherein the encoded bitstream explicitly identifies the changes. For decoding, the changes are extracted from the encoded bitstream and an updated VL decoding table is generated from a defined VL decoding table corresponding to the defined VL encoding table, based on the changes. The VL codes in the encoded bitstream are decoded using the updated VL decoding table to generate a set of decoded data.

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