Coding and decoding video signals
US5841470A · kind A · utility
15Cited by
4References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1995 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Jan 17, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Video signals are coded at a first relatively low frame rate. One or more portions of the image area, for example, the mouth of a person speaker: recognised by feature extractor, are coded at a higher frame rate. Preferably the second coding operates by resolving the pixel values of the image portion--considered as a vector--relative to a set or orthogonal reference vectors to produce coefficients which are then transmitted. Preferably, the feature extractor normalises the image portion as regards scaling, position and rotation and sends data on these parameters as side information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.