System and method for reducing multipass signal degradation
US6151361A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 1997 |
| Grant date | Nov 21, 2000 |
| Priority date | — |
| Expiry date | Dec 29, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/40
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method reduces multipass signal degradation attributable to non-linear processing, namely quantization and dequantization. In one embodiment, a decoder decodes a predetermined unit of data utilizing a first quantization value. A quantization restrictor receives the first quantization value and generates a second quantization value having a restricted value wherein the second quantization value is equal to the first quantization value divided by a given integer. An encoder encodes the predetermined unit of data utilizing the second quantization value. A function unit can be provided for performing a predetermined pixel domain function on the predetermined unit of data between the decoding operation of the decoder and the encoding operation of the encoder. In this system, the decoder performs an inverse discrete cosine transform on the predetermined unit of data, and dequantizes the predetermined unit of data. The encoder performs a discrete cosine transform on the predetermined unit of data, and quantizes the predetermined unit of data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.