| .TH IM_SGLDS_MATRIX 3 "10 May 1991" |
| .SH 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 |
| .SH SYNOPSIS |
| .B #include <vips/vips.h> |
| |
| int im_glds_matrix(im, m, xp, yp, xs, ys, dx, dy) |
| .br |
| .B IMAGE *im, *m; |
| .br |
| .B int xp, yp, xs, ys; |
| .br |
| .B int dx, dy; |
| |
| .B int im_glds_asm(m, asmoment) |
| .br |
| .B IMAGE *m; |
| .br |
| .B double *asmoment; |
| |
| .B int im_glds_contrast(m, contrast) |
| .br |
| .B IMAGE *m; |
| .br |
| .B double *contrast; |
| |
| .B int im_glds_entropy(m, entropy) |
| .br |
| .B IMAGE *m; |
| .br |
| .B double *entropy; |
| |
| .B int im_glds_mean(m, mean) |
| .br |
| .B IMAGE *m; |
| .br |
| .B double *mean; |
| |
| .SH DESCRIPTION |
| .B im_glds_matrix() |
| creates a 256 by 1 one channel spatial grey level difference 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 Cybernetics, Vol. |
| SMC-3, No 6, Nov. 1973, pp 610-621. |
| |
| .B 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. |
| |
| .B im_glds_contrast() |
| calculates the contrast of the sglds matrix held by m. The result is returned |
| into the location pointed by contrast. |
| |
| .B im_glds_entropy() |
| calculates the entropy of the sglds matrix held by m. The result is returned |
| into the location pointed by entropy. |
| |
| .B im_glds_mean() |
| calculates the mean of the sglds matrix held by m. The result is returned |
| into the location pointed by mean. |
| .SH RETURNED VALUES |
| All functions returns 0 on success and -1 on error. |
| .SH SEE\ ALSO |
| im_cooc_matrix(3) |
| .SH COPYRIGHT |
| .br |
| N. Dessipris |
| .SH AUTHOR |
| N. Dessipris \- 10/05/1991 |
