1PREDICATES(3) Library Functions Manual PREDICATES(3)
2
3
4
6 im_region_create, im_region_free - region creation and destruction
7
9 #include <vips/vips.h>
10 #include <vips/region.h>
11
12 REGION *im_region_create( im )
13 IMAGE *im;
14
15 int im_region_free( reg )
16 REGION *reg;
17
19 These functions create and destroy regions on images. Regions are used
20 for PIO, see accompanying documentation. Regions have type
21
22 typedef struct {
23 Rect valid /* Area of im represented */
24 IMAGE *im; /* im we are defined on */
25
26 ... more fields, all private and used for
27 ... housekeeping
28 } REGION;
29
30 im_region_create(3) returns a pointer to a new region, or NULL on
31 error. Regions are made blank, with no input or output possible. See
32 im_prepare(3), im_generate(3), im_start_one(3) and IM_REGION_ADDR(3).
33
34 im_region_free(3) frees a region and any resources associated with that
35 region. When an image is closed, all regions which have been created
36 on that image are automatically freed.
37
39 All int-valued functions return zero on success and non-zero on error.
40
42 National Gallery, 1993
43
45 `VIPS Library Programmers' Guide,' in accompanying documentation.
46
48 J. Cupitt - 23/7/93
49
50
51
52 11 April 1990 PREDICATES(3)