opencv-setMouseCallBack 鼠标事件响应

 1 void on_mouse(int event, int x, int y, int flags, void* userdata)
 2 {
 3     if (event == CV_EVENT_LBUTTONDOWN)
 4         cout << "触发左键按下" << endl;
 5     if (event == CV_EVENT_MOUSEMOVE)
 6         cout << "触发鼠标移动事件" << endl;
 7     if (event == CV_EVENT_RBUTTONDOWN)
 8         cout << "触发右键按下" << endl;
 9     if (event == CV_EVENT_LBUTTONUP)
10         cout << "触发左键抬起" << endl;
11     if (event == CV_EVENT_RBUTTONUP)
12         cout << "触发右键抬起" << endl;
13     if (event == CV_EVENT_LBUTTONDBLCLK)
14         cout << "触发左键双击" << endl;
15     if (event == CV_EVENT_RBUTTONDBLCLK)
16         cout << "触发右键双击" << endl;
17 }

 1 Point sp(-1, -1);
 2 Point ep(-1, -1);
 3 Mat temp;
 4 static void on_draw(int event, int x, int y, int flag,void *userdata)//每次操作鼠标位置对应x y
 5 {
 6     Mat image = *((Mat*)userdata);
 7     if (event == EVENT_LBUTTONDOWN)//点击时 鼠标位置 赋值给 sp.x sp.y 并打印出来
 8     {
 9         sp.x = x;
10         sp.y = y;
11         cout << "start point:" << sp << endl;
12     }
13     else if (event == EVENT_LBUTTONUP)//当鼠标抬起时 对应鼠标的位置传给 ep
14     {
15         //cout << "鼠标抬起";
16         ep.x = x;
17         ep.y = y;
18         //求出点击和抬起时的距离
19         int dx = ep.x - sp.x;
20         int dy = ep.y - sp.y;
21         if (dx > 0 && dy > 0)
22         {
23             Rect rect(sp.x, sp.y, ep.x - sp.x, ep.y - sp.y);//制作一个矩形
24             imshow("ROI区域", image(rect));
25             rectangle(image, rect, Scalar(0, 0, 255), 2, 8, 0);//将矩形绘制在图像上
26             imshow("鼠标绘制", image);//打印该图像
27             //为下一次准备——更新数据——防止一直跟随
28             sp.x = -1;
29             sp.y = -1;
30         }
31     }
32     else if (event == EVENT_MOUSEMOVE)
33     {
34         if (sp.x > 0 && sp.y > 0)
35         {
36             ep.x = x;
37             ep.y = y;
38             int dx = ep.x - sp.x;
39             int dy = ep.y - sp.y;
40             if (dx > 0 && dy > 0)
41             {
42                 Rect box(sp.x, sp.y, dx, dy);
43                 temp.copyTo(image);//防止打印成填充图形
44                 rectangle(image, box, Scalar(0, 255, 0), 2, 8, 0);
45                 imshow("鼠标绘制", image);
46             }
47         }
48         
49     }
50 }
51 void QuickColor::mouse_draw_demo(Mat& src)
52 {
53     temp = src.clone();
54     namedWindow("鼠标绘制", WINDOW_AUTOSIZE);
55     setMouseCallback("鼠标绘制", on_draw,(void *)(&src));
56     imshow("鼠标绘制", src);
57 }