MCUT(1) 1 (Nov 8, 1987) 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
Page 1 (printed 12/1/98)
MCUT(1) 1 (Nov 8, 1987) MCUT(1)
should be an option.
Page 2 (printed 12/1/98)
