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#include 
   
    #include 
    
     #include 
     
      using namespace std;using namespace  cv;Mat g_img;//全局变量，以便在mouse函数中进行使用string tile("窗口");//全局的窗口名字void Mouse(int event, int x, int y, int flag, void *){	static Point FirstPos;//第一次按下左键的鼠标点	static Point EndPos;	char text[100];//用于在图像中显示灰度值...用于显示鼠标移动过程中的坐标点	memset(text, 0, sizeof(char)* 100);	if (event==EVENT_LBUTTONDOWN)	{		FirstPos.x = x;		FirstPos.y = y;	}	if ((event==EVENT_MOUSEMOVE)&&(flag&EVENT_LBUTTONDOWN))	{		Mat temp = g_img.clone();//在临时变量中进行绘图操作		EndPos.x = x;		EndPos.y = y;		sprintf_s(text, "(%d,%d)", x, y);		putText(temp, text, EndPos, FONT_HERSHEY_SIMPLEX, 1, Scalar(0, 0, 255));		rectangle(temp, FirstPos, EndPos, Scalar(0, 255, 0), 1, CV_AA);		imshow(tile, temp);	}	if (event==EVENT_LBUTTONUP)	{		Mat temp = g_img.clone();		rectangle(temp, FirstPos, EndPos, Scalar(0, 255, 0), 1, CV_AA);		imshow(tile, temp);		//在另一个图像中绘制选择区域的直方图		string hist("Histgorm");		Mat ImgROI = temp((FirstPos.y < EndPos.y) ? Range(FirstPos.y, EndPos.y) : Range(EndPos.y, FirstPos.y), (FirstPos.x < EndPos.x ? Range(FirstPos.x, EndPos.x) : Range(EndPos.x, FirstPos.x)));		vector
      
        planes;		split(ImgROI, planes);//分解区域		float RangeB[] = { 0, 255 };		const float *range = { RangeB};		Mat histB, histG, histR;		int histSize = 255 / 8;//直方图的bin的数目		int channel = 0;		calcHist(&planes[0], 1, 0, Mat(), histB, 1, &histSize, &range,true,false);		calcHist(&planes[1], 1, 0, Mat(), histG, 1, &histSize, &range);		calcHist(&planes[2], 1, 0, Mat(), histR, 1, &histSize, &range);		int hist_w = 400; int hist_h = 400;		int bin_w = cvRound((double)hist_w / histSize);		Mat histImage(hist_w, hist_h, CV_8UC3, Scalar(0, 0, 0));//创建直方图影像		//将直方图的灰度进行归一化处理,防止越界		normalize(histB, histB, 0, histImage.rows, NORM_MINMAX);		normalize(histG, histG, 0, histImage.rows, NORM_MINMAX);		normalize(histR, histR, 0, histImage.rows, NORM_MINMAX);		//绘制直方图		for (int i = 1; i < histSize;++i)		{			line(histImage, Point(bin_w*(i - 1), hist_h - histB.at
       
        (i - 1)), Point(bin_w*(i), hist_h - histB.at
        
         (i)), Scalar(255, 0, 0)); line(histImage, Point(bin_w*(i - 1), hist_h - histG.at
         
          (i - 1)), Point(bin_w*(i), hist_h - histG.at
          
           (i)), Scalar(0, 255, 0)); line(histImage, Point(bin_w*(i - 1), hist_h - histR.at
           
            (i - 1)), Point(bin_w*(i), hist_h - histR.at
            
             (i)), Scalar(0, 0, 255)); } namedWindow(hist); imshow(hist, histImage); } return;}int main(){ string filename = "C:/Users/Administrator/Desktop/标准测试图片/dota/big32001.jpg"; g_img = imread(filename, IMREAD_COLOR); if (g_img.empty()) { return -1; } namedWindow(tile); setMouseCallback(tile, Mouse, NULL);//创建鼠标回调函数 imshow(tile, g_img); waitKey(0); return 0;}
            
           
          
         
        
       
      
     
    
   

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