Method and apparatus for increasing video data bandwidth by comparing video data for redundancy

摘要

This invention relates to a video graphic control method and controller for sending to a display device graphic data from a processing device, and the object thereof is to provide a video graphic controller that increases the bandwidth available to a graphic engine or CPU without increasing power consumption or manufacturing costs, even when used with a conventional frame memory. A video graphic controller for controlling video data by storing the video data from a CPU 4 in a frame memory 18 and causing the frame memory 18 to output the data to a display device 30 uses a video data comparison means 20 to compare a piece of video data stored in the N-th address of the frame memory 18 to another piece of video data stored in the N-1-th address in order to determine whether the two pieces of data match, and if the two pieces of data match, outputs to the display device 30 the piece of video data stored in the N-1-th address instead of the piece of video data stored in the N-th address.