Method of frame-by-frame calculation of quantization matrices
US6067118A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1997 |
| Grant date | May 23, 2000 |
| Priority date | — |
| Expiry date | Dec 16, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/124
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of reducing distortion in a video signal by coding a video frame utilizing a quantization matrix specifically determined for the video frame. The method includes the steps of determining the degree to which the video signal is spread about an average value, determining an average quantizer scale-value Q for the video frame, determining a reference weighted distortion for all DCT frequency bands in the video frame, determining the quantization parameter through a normalized distortion function, determining each weight for each DCT frequency band and coding the video frame taking into account the determined weights in the quantization matrix.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.