im_slice3
Threshold an image
Part of im_thresh(3).
Usage
#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;
Overview
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.
Releases
Unchanged in 4 releases since Debian 3.1 (Sarge).