US Patent 7630577 Image processing apparatus using alpha plane and method thereof

In an image processing apparatus and method, image data includes both color and alpha components. During processing, only the color component of the image data is stored in a memory. Display image data are then generated in response to the color component data retrieved from the memory and the alpha component data that were not stored in the memory. In this manner, by not storing the alpha component data in the memory, the memory access load by the image processing system is reduced.