ref: dd7352fd35491a753a47aca3acd9f3a2fd8c2d96
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}"