Method of correcting an image signal decoded in block units
US5337088A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 7, 1993 |
| Grant date | Aug 9, 1994 |
| Priority date | — |
| Expiry date | Sep 7, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/86
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In signal processing method, bandwidth compression codes an image signal by blocks of plural proximal pixels, and outputs the decoded signal after decoding by the same block units. When a level difference occurs during decoding at the border between adjacent blocks, the level of the pixels near the block border is corrected so that the level difference is reduced before outputting the decoded signal. In addition, if the level difference between two pixels within the same block and at the border thereof is less than a predetermined level during decoding, and the difference between the level of two border pixels in adjacent blocks is greater than the level difference of the two pixels within the same block, the decoded signal is output after pixel level correction is applied near the block border to reduce the level difference of the two pixels in the adjacent blocks. Thus, the level difference between blocks is smoothed, and visual image deterioration resulting from block distortion can be greatly improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.