efficient Jmap

edge indicator robust to noise and texture

This file is a fast computation of Jmap, which introduce in [1]. Jmap is an edge indicator which insensitive to noise and texture.
sample usage:
1.compile:
mex scale_sum.cpp
2. read an image:
img = imread('tiger.jpg');
3.Jmap computation:
Jmap = cmp_Jmap(img, 3, 7);
4. display image:
subplot(1, 2, 1), imshow(img, []), title("original image");
subplot(1, 2, 2), imshow(Jmap, []), title("Jmap");
reference:
[1]Yining Deng, B.S. Manjunath, Hyundoo Shin, "Color Image Segmentation,"
cvpr, vol. 2, pp.2446, 1999 IEEE Computer Society Conference on Computer
Vision and Pattern Recognition (CVPR'99)- Volume 2, 1999