ERROR DIFFUSION FOR COLOR IMAGES WITH SEMI-VECTOR QUANTIZATION

摘要

A method for color error diffusion using semi-vector quantizationis proposed that simplifies error diffusion calculations. When three colorseparations are used, the two separations with the most visually perceptivecolor output are compared with one another to determine their output colors,while the third, least visually perceptive separation, is treated separately.Acorrection term may be applied to the third separation based on the coloroutput of the first two separations to insure uniformity of ink coverage. Thismethod yields results close to vector quantization and also minimizesfluctuation in the two most visually perceptive output colors. Of course, thismethod may be used with more than three color separations. For example,when four color separations are used, the least visually perceptive color isprocessed differently than the three other color separations.