自己实现了用于空间平滑滤波的函数:
CImg<int> Smooth_filter(CImg<int> img, int num) {
CImg<int> m(num, num);
cimg_forXY(m, x, y) {
m(x, y) = 1;
}
int w = img.width(), h = img.height();
int k = (num - 1) / 2;
CImg<int> pic(w, h, 1, 1);
pic = img;
pic.resize(w + 2 * k, h + 2 * k, 1, 1);
CImg<int> pic1 = pic;
if (num % 2 == 0) {
cout << "不合法" << endl;
}
else {
CImg<int> temp(w,h,1,1);
cimg_forXY(pic, x, y) {
if (x >= k && y >= k && x <= w + k - 1 && y <= h + k - 1) {
CImg<int> t(num, num);
for (int i = 0; i < num; i++) {
for (int j = 0; j < num; j++) {
t(i, j) = pic1(x-k+i, y-k+j);
}
}
double sum = 0.0;
cimg_forXY(t, i1, j1) {
cimg_forXY(m, i2, j2) {
if (i1 + i2 - k == 1 && j1 + j2 - k == 1) {
sum += (double)t(i1, j1)*m(i2, j2);
}
}
}
pic(x, y) = sum / num / num;
}
}
}
return pic;
}
使用3*3的矩阵进行平滑滤波后的效果:
CImg<int> median_filter(CImg<int> img, int num) {
int w = img.width(), h = img.height();
int k = (num - 1) / 2;
CImg<int> pic(w, h, 1, 1);
pic = img;
pic.resize(w + 2 * k, h + 2 * k, 1, 1);
CImg<int> pic1 = pic;
if (num % 2 == 0) {
cout << "不合法" << endl;
}
else {
CImg<int> temp(w, h, 1, 1);
cimg_forXY(pic, x, y) {
if (x >= k && y >= k && x <= w + k - 1 && y <= h + k - 1) {
CImg<int> t(num, num);
int a = num * num;
int *filter;
filter = new int[a];
for (int i = 0; i < num; i++) {
for (int j = 0; j < num; j++) {
t(i, j) = pic1(x - k + i, y - k + j);
filter[i*num + j] = t(i, j);
}
}
sort(filter,filter+a);
pic(x, y) = filter[(a + 1) / 2 - 1];
}
}
}
return pic;
}