libvips/man/im_region_create.3
2007-08-31 13:01:42 +00:00

41 lines
1.1 KiB
Groff

.TH PREDICATES 3 "11 April 1990"
.SH NAME
im_region_create, im_region_free \- region creation and destruction
.SH SYNOPSIS
.B #include <vips/vips.h>
.br
.B #include <vips/region.h>
REGION *im_region_create( im )
.br
IMAGE *im;
int im_region_free( reg )
.br
REGION *reg;
.SH DESCRIPTION
These functions create and destroy regions on images. Regions are used for
PIO, see accompanying documentation. Regions have type
typedef struct {
Rect valid /* Area of im represented */
IMAGE *im; /* im we are defined on */
... more fields, all private and used for
... housekeeping
} REGION;
im_region_create(3) returns a pointer to a new region, or NULL on error.
Regions are made blank, with no input or output possible. See im_prepare(3),
im_generate(3), im_start_one(3) and IM_REGION_ADDR(3).
im_region_free(3) frees a region and any resources associated with that
region. When an image is closed, all regions which have been created on that
image are automatically freed.
.SH RETURN VALUE
All int-valued functions return zero on success and non-zero on error.
.SH COPYRIGHT
National Gallery, 1993
.SH AUTHOR
J. Cupitt \- 23/7/93