Method and system for processing video data including foreground extraction
US7978917B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2005 |
| Grant date | Jul 12, 2011 |
| Priority date | — |
| Expiry date | Nov 5, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V20/52
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In an intelligent video surveillance system, video processing software performs a number of operations on video data received from a camera, including foreground extraction, shadow removal and object tracking. The foreground extraction stage classifies each pixel of a received frame as representing either foreground or background. Since shadow regions can be wrongly classified as foreground, a two-branch shadow removal operation is employed, comprising weak shadow removal (32) and strong shadow removal (33). The purpose of weak shadow removal (32) is to remove only the most severe shadows in each frame. Conversely, the purpose of strong shadow removal (33) is to remove substantially every shadow present in each frame. By comparing the overlap of foreground regions in the two resulting images, it is possible to identify foreground regions that have fragmented due to strong shadow removal, and thereafter classify them as representing a common foreground object. Foreground objects are better defined in terms of their shape and subsequent processing stages will not treat fragmented regions as representing separate objects.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.