ref: 47ec5de29e56c4cf223e0582b930b88ca2a589ee
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}"