Method of coding a video signal for transmission in a restricted bandwidth
US4862264A · kind A · utility
85Cited by
5References
35Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 5, 1987 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Oct 5, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/98
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal is coded for transmission in a restricted bandwidth by sub-dividing a frame of picture information into a set of constituent blocks, measuring the amount of picture activity in each block, sampling the information in each block at a rate related to the amount of picture activity in that block, and adding to the coded block a supplementary signal indicating the sampling rate used for the block. Thus a decision is made on a block-by-block basis as to whether the block is transmitted with full accuracy or whether it can be adequately reconstructed from the previous frames.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.