ppmhist Man page

ppmhist General Commands Manual ppmhist

NAME

ppmhist – print a histogram of a portable pixmap

SYNOPSIS

ppmhist [-hexcolor] [-noheader] [-map] [-nomap] [-sort={frequency,rgb}] [ppmfile]

DESCRIPTION

Reads a PPM image as input. Generates a histogram of the colors in the
image, i.e. a list of all the colors and how many pixels of each color
are in the image.

OPTIONS

-sort={frequency,rgb}
The -sort option determines the order in which the colors are
listed in the output. frequency means to list them in order of
how pixels in the input image have the color, with the most rep‐
resented colors first. rgb means to sort them first by the
intensity of the red component of the color, the of the green,
then of the blue, with the least intense first.

The default is frequency.

-hexcolor
Print the color components in hexadecimal. Default is decimal.

-noheader
Do not print the column headings.

-map Generates a PPM file of the colormap for the image, with the
color histogram as comments.

-nomap Generates the histogram for human reading. This is the default.

SEE ALSO

ppm(5), pgmhist, ppmtomap, pnmhistmap, ppmchange

AUTHOR

Copyright (C) 1989 by Jef Poskanzer.

17 September 2000 ppmhist