Video image quality
US7542600B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2004 |
| Grant date | Jun 2, 2009 |
| Priority date | — |
| Expiry date | Apr 3, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30201
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Video image quality may be improved by correcting exposure levels and/or enhancing contrast amounts on each frame. One or more of the following phases may be implemented: skin-color model building, face detecting, exposure level correcting, and contrast enhancing. In a described implementation, a Gaussian skin-color model is built for each image frame during runtime. The Gaussian skin-color model is built with training pixels that are selected responsive to a defined skin color range, which is created offline from manually-selected skin pixels of multiple test sequences. In another described implementation, each pixel of an image frame is re-exposed using a ratio of contrast amount control variables (CACVs). More specifically, a pixel may be converted to a corresponding light intensity using a first CACV, and the corresponding light intensity may be reconverted to a pixel using a second CACV to enhance the contrast and possibly reduce fuzziness of the image frame.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.