Patent US 4,991,122

A method and apparatus for assigning color values (or gray scale) to picture display locations. A large frame buffer is written into with each memory location (preferably one bit) corresponding to a separate element of an image. The frame buffer contents are then mapped into a smaller space. The frame buffer memory has a color value assigned to each location of the memory. The memory has a larger number of locations than the number of color picture display locations. Each location is also assigned one of a plurality of weights. A number of color patterns are created and stored, with each color pattern being a bit pattern designed to produce the desired color when applied to the color values of the memory locations. A representation of a desired image is written into the memory using the color patterns, with each memory location corresponding to a separate element of the image. A group of bits in adjacent memory locations are combined with their weighting factors to produce each color value for each color picture display location.