ppmflash --version (return code: 0)
ppmflash: Using libpbm from Netpbm Version: Netpbm 10.0
ppmflash: BSD defined
ppmflash: RGB_ENV='RGBDEF'
ppmflash: RGBENV= 'RGBDEF' (env vbl is unset)
ppmflash -h (return code: 1)
usage: ppmflash flashfactor [ppmfile]
flashfactor: 0.0 = original picture, 1.0 = total whiteout