BWTHRESH
1
BRL-CAD
BRL-CAD

# bwthresh

threshold a black-and-white bw file

      bwthresh
        val
        <
        file.bw

## DESCRIPTION

Bwthresh reads from standard input a stream of black-and-white data in bw 5 format and thresholds it among the vals, writing the resulting bw 5 data to standard output. The vals must appear on the command line in strictly increasing order.

The grey scale 0..255 is divided evenly into n+1 bins, and each pixel of input is compared to the vals, to determine which of the n+1 grey levels should be output.

## EXAMPLE

The command

bwthresh 37 143 < file.bw > file2.bw

performs the following mapping:

if (pixel_in < 37) pixel_out = 0 else if (pixel_in < 143) pixel_out = 128 else pixel_out = 255

## SEE ALSO

bwmod 1, bwstat 1, bw 5

## AUTHOR

BRL-CAD Team

## COPYRIGHT

This software is Copyright (c) 1991-2013 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>.