opencv实现鼠标在图像上选点

#include    
#include    
#include    






IplImage* src = 0;
IplImage* dst = 0;


void on_mouse(int event, int x, int y, int flags, void* ustc)
{
char temp[16];
CvPoint pt;
CvFont font;
cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, CV_AA);


if (event == CV_EVENT_MOUSEMOVE)
{
cvCopy(dst, src);
sprintf(temp, "(%d,%d)", x, y);
pt = cvPoint(x, y);
cvPutText(src, temp, pt, &font, cvScalar(0, 20, 255, 0));
cvCircle(src, pt, 2, cvScalar(255, 0, 0, 0), CV_FILLED, CV_AA, 0);
cvShowImage("src", src);
}
else if (event == CV_EVENT_LBUTTONDOWN)
{
//cvCopy(dst,src);              
sprintf(temp, "(%d,%d)", x, y);
pt = cvPoint(x, y);
cvPutText(src, temp, pt, &font, cvScalar(255, 255, 255, 0));
cvCircle(src, pt, 2, cvScalar(255, 0, 0, 0), CV_FILLED, CV_AA, 0);
cvCopy(src, dst);
cvShowImage("src", src);
}
}


int main()
{
src = cvLoadImage("a.jpg", 1);
dst = cvCloneImage(src);


cvNamedWindow("src", 1);
cvSetMouseCallback("src", on_mouse, 0);


cvShowImage("src", src);


cvWaitKey(0);


cvDestroyAllWindows();
cvReleaseImage(&src);
cvReleaseImage(&dst);


return 0;
}