Bayer ordered dispersed dot dithering (order 2 dithering matrix)
Bayer ordered dispersed dot dithering (order 3 dithering matrix)
Ordered clustered dot dithering (order 8 - 16x16 matrix)
Ordered clustered dot dithering (order 3 - 6x6 matrix)
Ordered clustered dot dithering (order 4 - 8x8 matrix)
Floyd & Steinberg error diffusion
Threshold
It specifies the Dithering algorithm.