코드 8-7 영상의 투시 변환 예제 [ch08/perspective]

01    #include "opencv2/opencv.hpp"
02    #include <iostream>
03     
04    using namespace cv;
05    using namespace std;
06     
07    Mat src;
08    Point2f srcQuad[4], dstQuad[4];
09     
10    void on_mouse(int event, int x, int y, int flags, void* userdata);
11     
12    int main()
13    {
14        src = imread("card.bmp");
15     
16        if (src.empty()) {
17            cerr << "Image load failed!" << endl;
18            return -1;
19        }
20     
21        namedWindow("src");
22        setMouseCallback("src", on_mouse);
23     
24        imshow("src", src);
25        waitKey(0);
26     
27        return 0;
28    }
29     
30    void on_mouse(int event, int x, int y, int flags, void*)
31    {
32        static int cnt = 0;
33     
34        if (event = = EVENT_LBUTTONDOWN) {
35            if (cnt < 4) {
36                srcQuad[cnt++] = Point2f(x, y);
37     
38                circle(src, Point(x, y), 5, Scalar(0, 0, 255), -1);
39                imshow("src", src);
40     
41                if (cnt = = 4) {
42                    int w = 200, h = 300;
43     
44                    dstQuad[0] = Point2f(0, 0);
45                    dstQuad[1] = Point2f(w - 1, 0);
46                    dstQuad[2] = Point2f(w - 1, h - 1);
47                    dstQuad[3] = Point2f(0, h - 1);
48     
49                    Mat pers = getPerspectiveTransform(srcQuad, dstQuad);
50     
51                    Mat dst;
52                    warpPerspective(src, dst, pers, Size(w, h));
53     
54                    imshow("dst", dst);
55                }
56            }
57        }
58    }

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