IM_THRESH

Section: C Library Functions (3)
Updated: 26 April 1991
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NAME

im_thresh, im_slice - threshold an image  

SYNOPSIS

#include <vips/vips.h>

int im_thresh(in, out, threshold)
IMAGE *in, *out;
double threshold;

int im_slice(in, out, threshold1, threshold2)
IMAGE *in, *out;
double threshold1, threshold2;  

DESCRIPTION

These functions have been replaced with the relational and boolean packages - see im_lessconst() and im_and() for much better ways of doing this.

These functions operate on any non-complex input. The output image is a unsigned char image with the same sizes and the same number of channels as input.

im_slice() thresholds the image held by image descriptor in and writes the result on the image descriptor out. Output is a byte image with values less than threshold1) set to 0, values in [threshold1, threshold2) set to 128 and values greater than threshold2 set to 255 (x in range [a,b) means a<=x<b).

im_threshold() thresholds the image held by image descriptor in and writes the result on the image descriptor out. Output is a byte image with values less than threshold set to 0, and values greater or equal to threshold set to 255.  

RETURN VALUE

The function returns 0 on success and -1 on error.  

SEE ALSO

im_dilate(3), im_erode(3), im_lessconst(3), im_and(3).  

COPYRIGHT


N. Dessipris,  

AUTHOR

N. Dessipris - 26/04/1991