| 摘要 |
A device and method of forming a video frame from a video stream made up of a multiplexed plurality of sub-streams is disclosed. The method includes forming a foreground plane, forming a mask that represents opaque pixels in the foreground plane, and forming an underlying plane from at least one of the sub-streams and extracting a transparency value associated with each pixel in the foreground and underlying planes. Only those pixels in the underlying and foreground planes not covered by the mask, are blended in accordance with their associated transparency value in a buffer. The buffer is populated with opaque pixels from the foreground plane, at pixel locations corresponding to the mask. |
