thresLloyd
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Name
thresLloyd - threshold by the method of Lloyd
Syntax
#include <xite/threshold.h>
int thresLloyd( histogram h );
Description
thresLloyd calculates the threshold value by using
the method of Lloyd, 1985. Initially, the threshold
value is set to the average brightness. Then,
iteratively, the threshold is set to the average of
the mean of the pixels below the threshold, and the
mean of the pixels above the threshold , PLUS a
compensation factor depending on the varince of the
distribution. When the threshold value remains
constant, iteration terminates.
The actual thresholding is not performed, see the
routine "threshold".
Restrictions
Return value
The threshold value. Pixel values up to, and including,
the return value, is below the threshold.
Author
Tor L|nnestad, BLAB, ifi, UiO
Id
$Id: thresLloyd.c,v 1.17 1996/11/08 14:06:06 svein Exp $