bwhisteq [-v] file.bw > file.equalizedBWHISTEQ(1)
NAME
bwhisteq - equalize the histogram of a black and white image
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SYNOPSIS
DESCRIPTION
bwhisteq equalizes the histogram of a black and white bw(5) format file. It reads the specified input file and writes a remapped version of it to standard output. The values of the histogram are distributed to produce a constant average density while maintaining monotonicity.
OPTIONS
- -v
-
Print the pixel value mapping to standard error. For each original pixel value (0-255), it displays the corresponding new equalized value as result[N] = value.
EXAMPLES
Example 1. Improving contrast of a low-contrast image
$ bwhisteq image.bw > equalized.bwRemaps the pixel values of image.bw to produce a more uniform histogram, spreading out clustered intensities to improve apparent contrast, and saves the result to equalized.bw.
Example 2. Inspecting the remapping and viewing the result
$ bwhisteq -v image.bw 2> mapping.txt | bw-fbEqualizes image.bw while writing the value-to-value mapping table to mapping.txt, and pipes the equalized image directly to bw-fb(1) for display on a framebuffer.
SEE ALSO
brlcad(1), bwhist(1), bwstat(1), bw-fb(1), bw(5)
AUTHOR
BRL-CAD Team
COPYRIGHT
This software is Copyright (c) 1989-2026 by the United States Government as represented by U.S. Army Research Laboratory.
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org