Abstract: The present invention provides an optimal processing pipeline suitable for high quality video and graphics processing. According to the invention, color key extraction is performed before actual processing and transforming of the video/graphics data. This substantially minimizes the amount of artifacts in composed pictures. In accordance with the present invention, a video/graphics data processing pipeline is provided. The pipeline comprises a pre-processing circuit that is configured to pre-process a stream of digital video/graphics data and output pre-processed data; a color key processing circuit, operably coupled to the pre-processing circuit, that is configured to extract a color key from the pre-processed data and output resulting data; and a processing/transforming circuit, operably coupled to the color key processing circuit, that is configured to process and transform the resulting data.

Abstract: A raster generator sequences through a list of line descriptors to produce a screen raster. The line descriptors include a line-count parameter and a line-type parameter. The line-type parameter defines the characteristics of each type of raster line, and the line-count parameter defines the number of lines of this type occurring in the sequence of lines that define the entire video or image frame. For efficient encoding, the characteristics of each type of raster line is defined in terms of a list of raster pattern types, each raster pattern type being further defined in terms of a sequence of specified durations of particular raster values. The raster generator sequences through the lists of line descriptors, raster patterns, and duration-value pairs, in a nested fashion, thereby generating the screen raster pattern as a sequence of individual raster values that occur for specified durations within each line of each frame.