Abstract: A display controller, implemented in software or hardware, maintains the primary display image visible on a computer monitor in compressed subregions or chunks. The controller emulates a conventional frame buffer by making the compressed image appear as if it has a linear address space. Most of the image is compressed and the remainder is selectively decompressed and cached to satisfy read and write requests. To display the image, the controller decompresses the display image's constituent subregions and buffers the decompressed data so that it can be scanned out to a display monitor.