Variable rate coder
US5159611A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1992 |
| Grant date | Oct 27, 1992 |
| Priority date | — |
| Expiry date | Mar 27, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A variable rate coder for transforming an input signal into a low bit rate digital signal, comprising: a plurality of coding units each comprising an output quantizer having a different number of output bits, and each independently transforming the input signal into a respective compressed digital signal. A plurality of bit rate determined circuits are provided to determine an output of one of the plurality of coding units as a candidate output of the coder by a respective individual determining method, in which method, the quality of the signal which is regenerated from the output of each coding unit is compared with an individual predetermined quality evaluating standard, and then the candidate output of the coding unit having the smallest number of output bits, among the candidate outputs of coding units satisfying each standard, is determined as the actual output of the coder. One candidate output, among the plurality of the determined candidate outputs and, which is further determined by a most suitable determining method relative to the level of the input signal, thus is selected as the actual output of the coder. Further, when the number of the output bits in each of the cod…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.