Methods and apparatus for antialiasing using selective implementation of logical and averaging filter operations
US7295346B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2003 |
| Grant date | Nov 13, 2007 |
| Priority date | — |
| Expiry date | Jan 8, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30176
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus for antialiasing images that contain one or more image objects such as colored text, line art, and graphical objects, such that the edge pixels of an antialiased image object will exhibit relatively uniform values, and the appearance of the image object is thereby improved. In one embodiment, an improved antialiasing filter is employed to detect at least one region within the received image. Upon detecting a region containing a background image level that adjoins an image object having pixel values in a range other than a range of limit values, the antialiasing filter sets the pixel values of the edge or border pixels of the image object to substantially the same value. Selection among a logical filter operation and an averaging filter operation may be adaptively employed in the antialiasing filter in order to obtain the desired uniformity of pixel values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.