IM_SGLDS_MATRIX(3) IM_SGLDS_MATRIX(3)
NAME
im_glds_matrix, im_glds_asm, im_glds_contrast, im_glds_mean,
im_glds_entropy - calculate the spatial grey level difference matrix
and features on it
SYNOPSIS
#include <vips/vips.h>
int im_glds_matrix(im, m, xp, yp, xs, ys, dx, dy)
IMAGE *im, *m;
int xp, yp, xs, ys;
int dx, dy;
int im_glds_asm(m, asmoment)
IMAGE *m;
double *asmoment;
int im_glds_contrast(m, contrast)
IMAGE *m;
double *contrast;
int im_glds_entropy(m, entropy)
IMAGE *m;
double *entropy;
int im_glds_mean(m, mean)
IMAGE *m;
double *mean;
DESCRIPTION
im_glds_matrix() creates a 256 by 1 one channel spatial grey level dif-
ference matrix (sglds) of the box determined by the parameters (xp, yp;
xs, ys) within the image pointed by the IMAGE descriptor im. The
matrix is written onto the IMAGE descriptor m. The displacement vector
is determined by (dx, dy). The user must ensure that there is enough
border pixels around the box within im dictated by the displacement
vector (dx,dy) or else the program fails. im should be one-band
unsigned char.
All entries of the sgld matrix are double normalised to the number of
pairs involved. This function is a direct implementation of the paper:
Haralick R. M., Shanmugan K. and Dinstein I., 'Textural features for
image classification', IEEE Transactions on Systems, Man, and Cybernet-
ics, Vol. SMC-3, No 6, Nov. 1973, pp 610-621.
im_glds_asm() calculates the angular second moment of the co-occurrence
matrix held by m. The result is returned into the location pointed by
asmoment.
im_glds_contrast() calculates the contrast of the sglds matrix held by
m. The result is returned into the location pointed by contrast.
im_glds_entropy() calculates the entropy of the sglds matrix held by m.
The result is returned into the location pointed by entropy.
im_glds_mean() calculates the mean of the sglds matrix held by m. The
result is returned into the location pointed by mean.
RETURNED VALUES
All functions returns 0 on success and -1 on error.
SEE ALSO
im_cooc_matrix(3)
COPYRIGHT
N. Dessipris
AUTHOR
N. Dessipris - 10/05/1991
10 May 1991 IM_SGLDS_MATRIX(3)
im_glds_matrix 7.14.5 - Generated Sun Sep 7 10:53:23 CDT 2008