Encoding of a picture signal in consideration of contrast in each picture and decoding corresponding to the encoding
US5038389A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 24, 1988 |
| Grant date | Aug 6, 1991 |
| Priority date | — |
| Expiry date | Jun 24, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
On encoding an original picture signal comprising signal portions representative of original pictures, respectively, a contrast detecting unit (41) detects a measure of contrast in each picture in response to signal blocks representative of block areas, respectively, which have a common size in the picture in the manner known in transform encoding. Such measures are variable in a predetermined number of stages. With reference to the stages, a picture encoding parameter determiner (72) determines picture encoding parameters. Supplied with the encoding parameters, a picture encoder (71) encodes the original picture signal into an encoded picture signal. Inasmuch as the measures are detected in consideration of the signal blocks, the encoding is carried out on the signal blocks in effect. The contrast detecting unit, as herein called, preferably divides the pictures into a background region and a picture or non-background region so that the encoding parameters are determined with additional reference to the regions. The measures may be detected either among the block areas of each picture or among picture elements of each block area. More preferably, a complexity detecting unit is use…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.