Method of removing block phenomenon and ring phenomenon in compression coded image
US6594400B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1999 |
| Grant date | Jul 15, 2003 |
| Priority date | — |
| Expiry date | Aug 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/10016
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus to remove a block effect and a ring effect appearing in a compression-coded image is disclosed. The present invention is especially applicable to an image compression-coded at a low bit rate. In particular, the present invention includes a variety of masks for the removal of the block/ring effect. Thus, one mask is select for a pixel to be filtered. Moreover, candidate pixels to be averaged with the pixel to be filtered is selected from the pixels of the selected mask to better maintain the details of the image, and a weight is applied to improve the calculation speed of the averaging operation. More particularly, the masks according to the present invention have longer tabs toward adjacent blocks at boundaries of the given block to remove the block and ring effect.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.