MCUT(1)                                                 MCUT(1)





NAME
       mcut  - Quantize colors in an image using the median cut
       algorithm

SYNOPSIS
       mcut [ -n colors ] [ -d ] [ -o outfile ] infile

DESCRIPTION
       Mcut reads an RLE file and tries to  choose  the  "best"
       subset  of colors to represent the colors present in the
       original image.  A common use for this is to  display  a
       24  bit image on a frame buffer with only eight bits per
       pixel using a 24 bit color map.   Mcut  first  quantizes
       intensity  values from eight bits to five bits, and then
       chooses the colors from this space.

       Mcut runs in two passes; the first pass scans the  image
       to  find  the  color  distributions, and the second pass
       maps the original colors into color  map  indices.   The
       output  file  has a color map containing the colors mcut
       has  chosen.   Mcut  also  sets  the   picture   comment
       "color_map_length"  equal to the number of colors it has
       chosen.  The getx11 program (among others) will use this
       color map instead of dithering.

OPTIONS
       -n ncolors
              Limit  the  number  of  colors chosen to ncolors.
              The default is 200.

       -d     Uses Floyd/Steinberg dither to  hide  contouring.
              Greatly  improves images that have a small number
              of colors.

       infile The input will be read from this file.  If it  is
              a  multi-image file, each image will be quantized
              to its own colormap.  Piped input is not allowed.

       -o outfile
              If  specified,  output  will  be  written to this
              file, otherwise it will go to stdout.

SEE ALSO
       getx11(1), rlequant(1), urt(1), RLE(5),
       "Color Image Quantization for Frame Buffer Display",  by
       Paul Heckbert, Procedings of SIGGRAPH '82, July 1982, p.
       297.

AUTHOR
       Robert Mecklenburg,  John  W.  Peterson,  University  of
       Utah.

BUGS
       The  initial  quantization  is  hardwired  to five bits.
       This should be an option.




1                         Nov 8, 1987                   MCUT(1)
