Image signal processing apparatus utilizing a 2D Haar transform and adaptive selection of images based on a parameter such as a ratio of coefficients for reducing block distortion and method thereof
US5590222A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 14, 1994 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Nov 14, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/86
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique for processing a decoded image signal having a distortion obtained by decoding coded data by utilizing a two-dimensional inverse orthogonal transformation in which the coded data is obtained by coding an image signal by utilizing a two-dimensional orthogonal transformation. At least one correction block is constructed each including a plurality of pixels from a plurality of coded blocks from the decoded image signal and having a distortion on at least one boundary therebetween. The coded blocks of each correction block are adjacent to one another. A two-dimensional orthogonal transformation of each the correction block is performed by utilizing a Haar function so as to form a plurality of coefficients including higher-order side coefficients, lower-order side coefficients and a dc coefficient. A correction value is added to the higher-order side coefficients in accordance with a predetermined number of the lower-order side coefficients when the predetermined number of the lower-order side coefficients have values other than zero so as to form a correction coefficient signal for each correction block. A two-dimensional inverse orthogonal transformation is performed on th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.