Coding parameter adaptive transform artifact reduction process
US5920356A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1996 |
| Grant date | Jul 6, 1999 |
| Priority date | — |
| Expiry date | Jun 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/86
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A post-processor for a decoded video sequence includes a digital noise reduction unit and an artifact reduction unit which significantly reduce blocking artifacts and mosquito noise in a video image. The post-processor uses both temporal and edge characteristics of the video image to enhance the displayed image. A coding parameter from a decoder is used in a coding parameter adaptive filter unit within an artifact unit to further enhance the perceived quality of the displayed image. The coding parameter for a particular macroblock is selected using a characteristic of that macroblock. The post-processor operates on a current frame of pixel data using information from the immediately preceding post-processed frame that is stored in a frame memory of the post-processor. The post-processor uses artifact reduction only on portions of the image that are not part of an edge, and are not part of a texture or fine detail area. Since artifact reduction is not utilized on these areas, the post-processed image is not softened in regions where it is easily noticed by the human eye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.