1. A method of performing spacial dithering upon a stream of data values representative of an image to be displayed on a display panel for forming a stream of dithered values, wherein each dithered value includes a number of valid bits that is less than a number of bits included in each data value, the method comprising steps of: a. removing a number of least significant bits from each of the stream of data values for forming a stream of truncated values, wherein the stream of truncated values includes a number of valid bits; and b. selectively decrementing each of the stream of truncated values according to a corresponding entry in a selected table for forming the stream of dithered values wherein the selected table is selected from a group of stored tables according to the bits removed from each truncated value.