Patent · US Expired

Method and apparatus for communicating digital information such as compressed video using treillis coded QAM

US5321725A · kind A · utility

135Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 1992
Grant dateJun 14, 1994
Priority date
Expiry dateJul 10, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N21/4382
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for communicating high definition television signals is provided. Video signals are divided into blocks of PCM data. The PCM data is processed using motion estimation and compensation to provide DPCM data. For each block, one of PCM and DPCM data is selected for transmission based on a predetermined criteria. The selected data is compressed using the discrete cosine transform to provide blocks of transform coefficients. The coefficients are quantized to improve their coding efficiency and variable length coded. The variable length coded coefficients are coded using a concatenated coding scheme with a Reed-Solomon outer code and trellis inner code to provide coded signals for transmission. The coded signals are transmitted using QAM.

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