Abstract: A CT scanner (10) non-invasively examines a region of interest of a patient to create an image representation that is stored in an image memory (14). Each pixel of the image representation has a relatively large number of bits of radiation intensity resolution, e.g. 14 bits or 16k levels, which is larger than the gray scale resolution of a conventional video monitor (24), e.g. 8 bits or 256 levels. A look-up table (38) digitally filters each pixel value with digital filter values to reduce the number of levels of each pixel value to the number of gray scale levels displayable by the video monitor. While the image is being displayed, the operator selectively adjusts the digital filtering to optimize the displayed image for the intended diagnostic purpose. During the vertical flyback or other non-display periods of the video monitor, a central processor (30) generates most significant bits of addresses that read digital filter longwords from a filter memory (44).

Abstract: A system is provided for a display of CT cine images stored in a hybridized memory including both dynamic random access memory (14) and video random access memory frame buffer (16). The system includes memory address space which is allocated between the VRAM and DRAM. Non-linear, chained direct memory access control (22) provides a system to write a series of 640.times.512 pixel images directly from the frame buffer at 60 frames per second. The chaining provides a means for skipping over unused addresses at the end of a display line, thus maximizing utilization of expensive VRAM memory.