Method and apparatus for source clipping a video image in a video delivery system
US5699277A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 1996 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Jan 2, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/148
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a video interface coupling a video camera to a host for displaying a video image from the video camera on a graphics display device coupled to the host, a method for clipping an obscured region of a video image, i.e., a region of the video image covered up on the graphics display device by a window in accordance with a window manager. The video image is clipped prior to being buffered in the graphics memory so that only the portion of the video image that is visible on the graphics display device is actually stored in a buffer in graphics memory. The video interface reads a list in main memory on the host. The list comprises at least one strip descriptor and from 1 to 15 tile descriptors per strip descriptor. A strip descriptor comprises a strip start and a strip end. A tile descriptor comprises a tile start and a tile length. The video interface clips the video image according to the strips and tiles in the clip list. For a given strip, clipping of the video image is performed from the tile start for the tile length specified by a tile descriptor while a scan line of the video image is in the range of a strip descriptor, i.e., between a strip start and a strip end specified by …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.