Add MedianSideWindowFilter.cpp

Author: BBuf

MedianSideWindowFilter.cpp

@@ -0,0 +1,162 @@
+//针对灰度图的中值滤波+CVPR 2019的SideWindowFilter
+//其他种类的滤波直接换核即可
+
+//记录每一个方向的核的不为0的元素个数
+int cnt[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+// 记录每一个方向的滤波器
+vector <int> filter[8];
+
+//初始化半径为radius的滤波器，原理可以看https://mp.weixin.qq.com/s/vjzZjRoQw7MnkqAfvwBUNA
+void InitFilter(int radius) {
+	int n = radius * 2 + 1;
+	for (int i = 0; i < 8; i++) {
+		cnt[i] = 0;
+		filter[i].clear();
+	}
+	for (int i = 0; i < 8; i++) {
+		for (int x = 0; x < n; x++) {
+			for (int y = 0; y < n; y++) {
+				if (i == 0 && x <= radius && y <= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 1 && x <= radius && y >= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 2 && x >= radius && y <= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 3 && x >= radius && y >= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 4 && x <= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 5 && x >= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 6 && y >= radius) {
+					filter[i].push_back(1);
+				}
+				else if (i == 7 && y <= radius) {
+					filter[i].push_back(1);
+				}
+				else {
+					filter[i].push_back(0);
+				}
+			}
+		}
+	}
+	for (int i = 0; i < 8; i++) {
+		int sum = 0;
+		for (int j = 0; j < filter[i].size(); j++) sum += filter[i][j] == 1;
+		cnt[i] = sum;
+	}
+}
+
+//实现Side Window Filter的中值滤波，强制保边
+Mat MedianSideWindowFilter(Mat src, int radius = 1) {
+	int row = src.rows;
+	int col = src.cols;
+	int channels = src.channels();
+	InitFilter(radius);
+	//针对灰度图
+	if (channels == 1) {
+		Mat dst(row, col, CV_8UC1);
+		for (int i = 0; i < row; i++) {
+			for (int j = 0; j < col; j++) {
+				if (i < radius || i + radius >= row || j < radius || j + radius >= col) {
+					dst.at<uchar>(i, j) = src.at<uchar>(i, j);
+					continue;
+				}
+				int minn = 256;
+				int pos = 0;
+				for (int k = 0; k < 8; k++) {
+					int val = 0;
+					int id = 0;
+					vector <int> now;
+					for (int x = -radius; x <= radius; x++) {
+						for (int y = -radius; y <= radius; y++) {
+							//if (x == 0 && y == 0) continue;
+							now.push_back(src.at<uchar>(i + x, j + y) * filter[k][id++]);
+							//val += src.at<uchar>(i + x, j + y) * filter[k][id++];
+						}
+					}
+					sort(now.begin(), now.end());
+					val = now[(2 * radius + 1)*(2 * radius + 1) / 2];
+					if (abs(val - src.at<uchar>(i, j)) < minn) {
+						minn = abs(val - src.at<uchar>(i, j));
+						pos = k;
+					}
+				}
+				int val = 0;
+				int id = 0;
+				vector <int> now;
+				for (int x = -radius; x <= radius; x++) {
+					for (int y = -radius; y <= radius; y++) {
+						//if (x == 0 && y == 0) continue;
+						now.push_back(src.at<uchar>(i + x, j + y) * filter[pos][id++]);
+						//val += src.at<uchar>(i + x, j + y) * filter[k][id++];
+					}
+				}
+				sort(now.begin(), now.end());
+				val = now[(2 * radius + 1)*(2 * radius + 1) / 2];
+				dst.at<uchar>(i, j) = val;
+			}
+		}
+		return dst;
+	}
+	//针对RGB图
+	Mat dst(row, col, CV_8UC3);
+	for (int c = 0; c < 3; c++) {
+		for (int i = 0; i < row; i++) {
+			for (int j = 0; j < col; j++) {
+				if (i < radius || i + radius >= row || j < radius || j + radius >= col) {
+					dst.at<Vec3b>(i, j)[c] = src.at<Vec3b>(i, j)[c];
+					continue;
+				}
+				int minn = 256;
+				int pos = 0;
+				for (int k = 0; k < 8; k++) {
+					int val = 0;
+					int id = 0;
+					vector <int> now;
+					for (int x = -radius; x <= radius; x++) {
+						for (int y = -radius; y <= radius; y++) {
+							//if (x == 0 && y == 0) continue;
+							//val += src.at<Vec3b>(i + x, j + y)[c] * filter[k][id++];
+							now.push_back(src.at<Vec3b>(i + x, j + y)[c] * filter[k][id++]);
+						}
+					}
+					val = now[(2 * radius + 1)*(2 * radius + 1) / 2];
+					if (abs(val - src.at<Vec3b>(i, j)[c]) < minn) {
+						minn = abs(val - src.at<Vec3b>(i, j)[c]);
+						pos = k;
+					}
+				}
+				int val = 0;
+				int id = 0;
+				vector <int> now;
+				for (int x = -radius; x <= radius; x++) {
+					for (int y = -radius; y <= radius; y++) {
+						//if (x == 0 && y == 0) continue;
+						//val += src.at<Vec3b>(i + x, j + y)[c] * filter[k][id++];
+						now.push_back(src.at<Vec3b>(i + x, j + y)[c] * filter[pos][id++]);
+					}
+				}
+				val = now[(2 * radius + 1)*(2 * radius + 1) / 2];
+				dst.at<Vec3b>(i, j)[c] = val;
+			}
+		}
+	}
+	return dst;
+}
+
+
+int main() {
+	Mat src = imread("F:\\1.jpg");
+	for (int i = 0; i < 10; i++) {
+		src = MedianSideWindowFilter(src, 3);
+	}
+	imwrite("F:\\res.jpg", src);
+	return 0;
+}

README.md

@@ -35,6 +35,7 @@
 - MedianFilterFogRemoval.cpp C++复现了《[一种单幅图像去雾方法](http://wenku.baidu.com/link?url=ZoNmd4noFbWZOGKCHus4anP83t8gcc0xWDu9QCfgQuzwn7LxUoBbZmMxrUAFYM3_YEMoQH3DdvYD8j1hdcHt5Wz4LhdvDe4_GZYXrqCYco3)》使用中值滤波进行去雾，原理请看：https://blog.csdn.net/just_sort/article/details/89520776
 - FastDefoggingBasedOnSingleImage.cpp C++复现了《基于单幅图像的快速去雾》论文，原理请看：https://blog.csdn.net/just_sort/article/details/90205686
 - BoxSideWindowFilter.cpp C++复现了CVPR2019《Side Window Filter》论文(Box Filter)，实现霸气的强制保边，原理请看：https://blog.csdn.net/just_sort/article/details/93664078
+- MedianSideWindowFilter.cpp C++复现了CVPR2019《Side Window Filter》论文(Median Filter)，实现霸气的强制保边，原理请看：https://blog.csdn.net/just_sort/article/details/93664078