ref: 766a641d252cf4de21d50b2753dd8c25490b8ba0
dir: /sys/src/cmd/gs/lib/ras3.upp/
-supModel="SUN rasterfile, 3 Bit, 7 Colors (RGB-Ghostscript)" -sDEVICE=uniprint -dNOPAUSE -dSAFER -dupColorModel=/DeviceRGB -dupRendering=/ErrorDiffusion -dupOutputFormat=/SunRaster -dupComponentBits="{1 1 1}"