6.5.3.3.7 Dither

Only a discrete number of intensity levels can be represented. This discretization leads to a total error in the color intensities of an image equal to the square root of the sum of the squares from each point.

This error results in contouring. In an image where intensities change slowly, this will cause noticeable jumps. Dithering can be used to diffuse the intensity across neighboring pixels.

In Dithering mode, pixels are scanned in order, and errors in calculating a pixel's intensity are distributed (i.e., diffused) to neighboring pixels to keep the overall intensity of the image closer to the input intensity.

Dithering is supported for 16-bit color destination formats. The dither table is programmable by software.