US00RE37476B1
(io) Patent Number: US RE37,476 E
(45) Date of Reissued Patent: Dec. 18,2001
(54) ALPHA BLENDING PALETTIZED IMAGE DATA
(75) Inventor: Richard Gerber, San Francisco, CA (US)
(73) Assignee: Intel Corporation, Santa Clara, CA (US)
(21) Appl. No.: 09/538,666
(22) Filed: Mar. 28, 2000
Related U.S. Patent Documents
Palettized image data for two or more images, represented by color lookup table (CLUT) indices, are mapped to an index space. Blended pixels are generated from the pixels in the index space using alpha blending. The blended pixels are mapped back to CLUT indices to generate palettized blended image data. In a preferred embodiment, in which the CLUT is generated based on a characterized structure in YUV space, the CLUT indices are mapped to Y and UV indices in a YUV index space. The Y and UV indices are then used to generate three-coordinate blended pixels. The three-coordinate blended pixels are then mapped back to CLUT indices of a palettized blended image. Table lookups are used to generate the blended pixels from the Y and UV indices and to map the blended pixels back to CLUT indices.
30 Claims, 12 Drawing Sheets
