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GIFHISTO(1) GIFLIB Documentation GIFHISTO(1)
NAME
gifhisto - make a color histogram from GIF colr frequencies
SYNOPSIS
gifhisto [-v] [-t] [-s width height] [-n image-number] [-b] [-h]
[gif-file]
DESCRIPTION
A program to create histogram of number of pixels using each color. The
output can be formatted into a GIF histogram file, or as text file -
both go to stdout.
If no GIF file is given, gifhisto will try to read a GIF file from
stdin.
OPTIONS
-v
Verbose mode (show progress). Enables printout of running scan
lines.
-t
Force output to be text file of the following form: (colormap size)
lines each containing two integers: number of times color appeared,
and color index. Lines are in increasing color index order. This
output can be fed directly to a sort program if ordering by color
frequency is desired.
The colormap picked is the one to be used for the image to generate
histogram for, as defined in GIF format.
-s width height
Size of GIF histogram file. The height of the histogram should be
power of 2 dividable by number of colors in colormap.
Width sets the resolution (accuracy if you like) of the histogram
as the maximum histogram bar is scaled to fit it.
-n image-number
Image number to test. Default is one.
-b
Zeros the background color count. As only linear scale bars are
supported and usually the background appears much more often then
other colors, deleting the background count will improve the
scaling of other colors.
-h
Print one line of command line help, similar to Usage above.
AUTHOR
Gershon Elber
GIFLIB 2 May 2012 GIFHISTO(1)