Variable length code word decoder for use in digital communication systems
US5233348A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1992 |
| Grant date | Aug 3, 1993 |
| Priority date | — |
| Expiry date | Mar 26, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus is provided for decoding variable length code words to recover transform coefficients, such as DCT transform coefficients provided by a high definition television encoder. A first category of the code words has a length of no more than n bits. A second category has a length of greater than n bits. A feedback ROM is used to decode the code words. Code words from the first category are processed by directly addressing a lookup table in the ROM. Code words from the second category are processed using multiple passes through the ROM, wherein a portion of the data output during a prior pass is fed back to address the memory during a subsequent pass.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.