NAME

24to8 − convert a 24 bit rasterfile to an 8 bit one suitable for X11/NeWS. 

SYNOPSIS

24to8 [ −v ] [ −q ] [ −large ] [ inrasf | − ] [ outrasf ]

DESCRIPTION

24to8 takes as input a 24 bit Sun rasterfile(5) and reduces the depth of the image, from truecolor to 8 bit colormapped index color. 24to8 uses Floyd/Steinberg dithering to achieve high quality images while maintaining the X11/NeWS static colormap.  By default, this filter assumes that the color cube in the static colormap is of the form 5x5x5 (5 reds, 5 greens, and 5 blues).
 
If both filenames are missing, the source rasterfile is read from stdin and the output rasterfile is written to stdout.  If there is only one filename, then it is interpreted as the input rasterfile.  To have a named output rasterfile and still read the input rasterfile from stdin, use a dash (-) in place of the input filename.
 
24to8 interprets the input rasterfile as BGR format, the standard Sun ordering for the red, green, and blue channels.  This is the opposite of older versions of this program, which used the non-standard RGB format.  Older image files with the RGB format should be passed through the redxblue filter prior to dithering with 24to8
 

OPTIONS

−v Verbose mode will print information as it processes the image.  (The default is to be silent.) 

−q Query (prints list of options)

−large
Dithers into a static colormap with a large color cube of the form 5x9x5.  This option is for compatibility with the X11/NeWS server command line option ’-cubesize large’.

SEE ALSO

redxblue(1)

{:heading=>"24TO8\|(\|1\|)\0\0\(em\0\0\∗(]D"}  —  Last change: 7 May 1990  —  Last change: 7 May 1990