1IM_THRESH(3) Library Functions Manual IM_THRESH(3)
2
3
4
6 im_thresh, im_slice - threshold an image
7
9 #include <vips/vips.h>
10
11 int im_thresh(in, out, threshold)
12 IMAGE *in, *out;
13 double threshold;
14
15 int im_slice(in, out, threshold1, threshold2)
16 IMAGE *in, *out;
17 double threshold1, threshold2;
18
20 These functions have been replaced with the relational and boolean
21 packages - see im_lessconst() and im_and() for much better ways of
22 doing this.
23
24 These functions operate on any non-complex input. The output image is
25 a unsigned char image with the same sizes and the same number of chan‐
26 nels as input.
27
28 im_slice() thresholds the image held by image descriptor in and writes
29 the result on the image descriptor out. Output is a byte image with
30 values less than threshold1) set to 0, values in [threshold1, thresh‐
31 old2) set to 128 and values greater than threshold2 set to 255 (x in
32 range [a,b) means a<=x<b).
33
34 im_threshold() thresholds the image held by image descriptor in and
35 writes the result on the image descriptor out. Output is a byte image
36 with values less than threshold set to 0, and values greater or equal
37 to threshold set to 255.
38
40 The function returns 0 on success and -1 on error.
41
43 im_dilate(3), im_erode(3), im_lessconst(3), im_and(3).
44
46 N. Dessipris,
47
49 N. Dessipris - 26/04/1991
50
51
52
53 26 April 1991 IM_THRESH(3)