Picture signal coding apparatus
US4238768A · kind A · utility
35Cited by
7References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1978 |
| Grant date | Dec 9, 1980 |
| Priority date | — |
| Expiry date | Nov 14, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/98
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A frame of a gray-scaled picture is divided into blocks, in each of which the mean luminance of picture elements is used as a threshold value for comparison with each picture element signal to classify it into 0 or 1 according to its magnitude to provide a resolution component. From the resolution component and each picture element signal in the block are calculated two gray components; the resolution component and the two gray components are used as coded outputs for each block.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.