ref: 2eadf1fa1703e5da4a98ba9c1a2bdc23bd140d8c
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}"