Patent · US Expired

Method of coding a digital signal, method of generating a coding table, coding apparatus and coding method

US5510785A · kind A · utility

62Cited by
13References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 17, 1994
Grant dateApr 23, 1996
Priority date
Expiry dateMar 17, 2014

Classification

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

Abstract

Generating a plurality of tables based on a condition series, such as non-zero coefficient size groupings, by repeatedly executing an operation in which the quantization step of a quantizer is controlled by supplying the total code word length generated by a variable length coder to the quantizer. Coefficient data is coded by selecting a table based on a preceding condition series and the current condition series is coded based on the selected table. Thus, the total code word length is decreased. The coding apparatus includes a Huffman table generating apparatus, a transform circuit, a quantizer, and a variable length coder having a memory for storing the Huffman tables for every condition series.

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