OpenCV官方文档学习记录（16）

 1 #include <opencv2\opencv.hpp>
 2 #include <iostream>
 3 #include <string>
 4 
 5 #pragma comment( linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"" )
 6 
 7 using namespace std;
 8 using namespace cv;
 9 
10 int main(void)
11 {
12     //载入图片
13     Mat src = imread("lena.jpg");
14     if (src.empty())
15         return -1;
16     namedWindow("src", CV_WINDOW_AUTOSIZE);
17     imshow("src", src);
18 
19     //按照原图片格式构建结果图片
20     Mat dst;
21     dst.create(src.size(), src.type());
22 
23     //灰度转化
24     Mat src_gray;
25     cvtColor(src, src_gray, CV_BGR2GRAY);
26     namedWindow("Step 1 - src_gray", CV_WINDOW_AUTOSIZE);
27     imshow("Step 1 - src_gray", src_gray);
28 
29     int threshold = 100;
30     int kernel_size = 3;
31     //定义比例
32     int ratio = 3;
33 
34     //高斯变换，降噪
35     Mat detected_edges;
36     blur(src_gray, detected_edges, Size(3, 3));
37     namedWindow("Step 2 - detected_edges", CV_WINDOW_AUTOSIZE);
38     imshow("Step 2 - detected_edges", detected_edges);
39 
40     //应用Canny变换，使用降噪后的图片（Canny recommended a upper:lower ratio between 2:1 and 3:1.*来自文档*）
41     Canny(detected_edges, detected_edges, threshold, threshold*ratio, kernel_size);
42     namedWindow("Step 3 - detected_edges", CV_WINDOW_AUTOSIZE);
43     imshow("Step 3 - detected_edges", detected_edges);
44 
45     //用0填充
46     dst = Scalar::all(0);
47 
48     //进行遮罩处理
49     src.copyTo(dst, detected_edges);
50 
51     namedWindow("dst", CV_WINDOW_AUTOSIZE);
52     imshow("dst", dst);
53 
54     waitKey();
55     return 0;
56 }