Digital video signal encoder and encoding method
US5903673A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1997 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Mar 14, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/152
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A motion video signal encoder maximizes image quality without exceeding transmission bandwidth available to carry the encoded motion video signal by comparing encoded frames of the motion video signal to a desired size of frame. If the size of encoded frames differ from the desired size, quantization is adjusted to produce encoded frames closer in size to the desired size. In addition, a cumulative bandwidth balance records an accumulated amount of available bandwidth. The cumulative bandwidth balance is adjusted as time elapses to add to the available bandwidth and as each frame is encoded to thereby consume bandwidth. If the cumulative bandwidth balance deviates from a predetermined range, quantization is adjusted as needed to either improve image quality to more completely consume available bandwidth or to reduce image quality to thereby consume less bandwidth. Rapid changes in the amount of change or motion in the motion video signal are detected by comparing the amount of change between two consecutive frames and the amount of change between the next two consecutive frames. Quantization is precompensated according to the measured rapid change. Conditional replenishment is impr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.