Adaptive variable length encoder/decoder
US5400075A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 13, 1993 |
| Grant date | Mar 21, 1995 |
| Priority date | — |
| Expiry date | Jan 13, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A variable length encoding/decoding system for use with a layered signal format, and for adaptively providing VLC changes without additional signal overhead, includes a plurality of VLC encoding tables, respective ones of the tables being preprogrammed with VLC codes associated with anticipated signal statistics. The layered signal includes blocks of data subject to common parameters which parameters may be associated with signal statistics. The blocks of data include information indicative of such parameters. Each packet is examined for the common parameter and responsive thereto a default VLC coding/decoding table is assigned. In a further embodiment the VLC table used for each successive codeword is made dependent upon the table utilized for the lastmost codeword and the relative value of the lastmost codeword.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.