QUANTIZE(9.1)                                       QUANTIZE(9.1)

     NAME
          3to1, mcut, improve, quantize, dither - picture color
          compression

     SYNOPSIS
          fb/3to1 [ -e ] colormap [ input ]

          fb/mcut [ input ]

          fb/improve colormap [ input ]

          fb/quantize [ input ]

          fb/dither [ input ]

     DESCRIPTION
          3to1 approximates the full color (3 bytes per pixel) or
          mapped (1 byte per pixel, possibly with a colormap) input
          picture file in one byte per pixel using the given colormap.
          If no input file is named, the picture is read from standard
          input.  The -e option suppresses the default error-diffusion
          dither.

          Mcut writes a color map, suitable for use by 3to1 on its
          standard output.  The color map is computed using the
          median-cut algorithm and represents reasonably well, but not
          necessarily optimally, the colors of the input picture.

          Improve reads a color map and a picture and writes on stan-
          dard output a new color map that better represents the col-
          ors of the picture.  Multiple passes of improve may produce
          better and better color maps.

          Quantize is an rc script that packages all of the above to
          compress the full-color input image to one byte per pixel.

          Dither likewise compresses full-color images to one byte per
          pixel.  It uses a fixed color map that allows a speedy algo-
          rithm; quantize instead runs slower but gives better
          results.

     SOURCE
          /sys/src/fb/3to1.c
          /sys/src/fb/mcut.c
          /sys/src/fb/improve.c
          /sys/src/fb/quantize.r
          /sys/src/fb/dither.c

     SEE ALSO
          picfile(9.6), cmap(9.6)

     QUANTIZE(9.1)                                       QUANTIZE(9.1)