[magick-users] How to create 4-bit grayscale bmp images?

[John Harragin]

x=209;y=109; jpegtopnm /var/www/html/photos/cyclamin.jpg | ppmtopgm | pnmscale -xsize=${x} -ysize=${y} | ppmquant 16 | ppmtobmp -bpp=4 > /var/www/html/photos/background.bmp

Thanks Anthony. This command gets the job done. identify still reports 8 bits depth but the file is indeed about half that of one with 256 colors - even if I leave the -bpp=4 option out.

John