METHOD FOR HALFTONING USING STOCHASTIC DITHERING WITH MINIMUM DENSITY VARIANCE

A dispersed-dot stochastic dither array is provided for rendering halftone images having excellent visual quality and are created by a minimum density variance method. The minimum density variance method considers the statistical distribution of the pixels in the image, and is unrelated to previous techniques based on either spatial frequencies or spatial distances, such as the blue noise mask and the void and cluster algorithm. By minimizing the variance in the number of dots within each local region of the image, a smooth and dispersed distribution of dots may be obtained. The method of the present invention also offers the flexibility to accommodate particular design considerations, through the selection of the size and shape of the image regions, the weighting of the cost function, and the option of guiding the selection of dots with "target" dot profile images.