OpenCV动态画矩形框

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#include "pch.h"
#include <iostream>
#include <opencv2\opencv.hpp>
using namespace cv;
using namespace std;

#define Mouse
Point pt;//起始点
Point endPoint;//鼠标移动点
bool IsMouseDown = false;
Mutex mutex;//锁定

void OnMouse(int event, int x, int y,int flags, void *param)//鼠标回调函数
{
	Mat img = *(Mat*)param;//*(Mat *)=Mat,	 
	switch (event)
	{
	case CV_EVENT_MOUSEMOVE:
		endPoint.x = x;
		endPoint.y = y;
		break;
	case CV_EVENT_LBUTTONDOWN:
		IsMouseDown = true;
		pt.x = x;
		pt.y = y;
		break;
	case CV_EVENT_LBUTTONUP:
		IsMouseDown = false;
		mutex.lock();
		if (!(endPoint.x < img.rows&&endPoint.y < img.cols))
		{
			endPoint.x = img.rows;
			endPoint.y = img.cols;
		}
		if(pt.x!=endPoint.x&&pt.y!=endPoint.y)
			imshow("clip", img(Rect(pt,endPoint)));
		mutex.unlock();
		break;
	}
}

int main()
{
#ifdef Mouse
	Mat img(500, 500, CV_8UC3, Scalar(255, 255, 255));
	namedWindow("mouse", CV_WINDOW_AUTOSIZE);
	setMouseCallback("mouse", OnMouse, &img);
	char tip[100];//文字显示
	while (1)
	{
		mutex.lock();
		{
			if (IsMouseDown&&pt != endPoint)
			{
				img = Mat(500, 500, CV_8UC3, Scalar(255, 255, 255));
				rectangle(img, pt, endPoint, Scalar(0, 255, 0), 2, 8);
				sprintf(tip, "endx:%d endy:%d",endPoint.x,endPoint.y);
				putText(img, tip, pt, CV_FONT_HERSHEY_SIMPLEX, 1, Scalar(0, 0, 0));
			}
			imshow("mouse", img);
		}
		mutex.unlock();
		if (27 == waitKey(10))
			break;
	}
#endif // Mouse
   
}