im_dif_std(3) im_dif_std(3)
NAME
im_dif_std - calculate the mean and the standard deviation of the dif-
ference image for a given displacement vector
SYNOPSIS
#include <vips/vips.h>
int im_dif_std(im, xp, yp, xs, ys, dx, dy, mean, std)
IMAGE *im;
int xp, yp, xs, ys;
int dx, dy;
double *mean, *std;
DESCRIPTION
im_dif_std() calculates the mean and the standard deviation of the dif-
ference image created by the displacement vector (dx,dy) on the box
(xp,yp;xs,ys) defined on the image pointed by im. More specifically
the difference image is of an image given the dispacement vector (dx,
dy) is defined as follows: For each point of the original image, the
start of the vector (dx,dy) is set on that point. The difference image
at this point is defined as the difference of the values pointed by the
vector (end value - start value). The function returns the mean and
the standard deviation of the difference images measured on the area
(xp,yp;xs,ys) of im.
Input im should be one band unsigned char image and it should have been
set by a call to im_mmapin(3) or im_setbuf(3).
RETURNED VALUES(3)
The function returns 0 on success and -1 on error.
SEE ALSO
im_cooc_matrix(3), im_glds_matrix(3)
COPYRIGHT
N. Dessipris
AUTHOR
N. Dessipris - 10/05/1991
10 May 1991 im_dif_std(3)
im_dif_std 7.14.5 - Generated Sun Sep 7 06:09:07 CDT 2008