ref: cb2a55aeb38ffa5ac168485ada6bbc44b4f88c1d
dir: /sys/src/cmd/gs/lib/ras24.upp/
-supModel="SUN rasterfile, 24 Bit, 7 Colors (RGB-Error-Diffusion)" -sDEVICE=uniprint -dNOPAUSE -dSAFER -dupColorModel=/DeviceRGB -dupRendering=/ErrorDiffusion -dupOutputFormat=/SunRaster -dupComponentBits="{8 8 8}"