鼠标绘制矩形

程序之一，在OpenCV中利用鼠标绘制矩形

 #include <cv.h>
 #include <highgui.h>
 #include <stdio.h>
 #pragma comment( lib, "cv.lib" )
 #pragma comment( lib, "cxcore.lib" )
 #pragma comment( lib, "highgui.lib" )
 IplImage* src = 0;
 IplImage* dst = 0;
 void on_mouse( int event, int x, int y, int flags, void* ustc)
 {
     static CvPoint pre_pt = {-1,-1};
     static CvPoint cur_pt = {-1,-1};
     CvFont font;
     cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, CV_AA);
     char temp[16];

     if( event == CV_EVENT_LBUTTONDOWN )
     {
         cvCopy(dst,src);
         sprintf(temp,"(%d,%d)",x,y);
         pre_pt = cvPoint(x,y);
         cvPutText(src,temp, pre_pt, &font, cvScalar(0,0, 0, 255));
         cvCircle( src, pre_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 );
         cvShowImage( "src", src );
         cvCopy(src,dst);
     }
     else if( event == CV_EVENT_MOUSEMOVE && !(flags & CV_EVENT_FLAG_LBUTTON))
     {
         cvCopy(dst,src);
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(src,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvShowImage( "src", src );
     }
     else if( event == CV_EVENT_MOUSEMOVE && (flags & CV_EVENT_FLAG_LBUTTON))
     {
         cvCopy(dst,src);
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(src,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvRectangle(src, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, 8, 0 );
         cvShowImage( "src", src );
     }
     else if( event == CV_EVENT_LBUTTONUP )
     {
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(src,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvCircle( src, cur_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 );
         cvRectangle( src, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, 8, 0 );
         cvShowImage( "src", src );
         cvCopy(src,dst);
     }
 }
 int main()
 {
     src=cvLoadImage("lena.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;
 }

效果图如下

 

程序之二，在OpenCV中利用鼠标绘制矩形并截取该矩形区域的图像

 #include <cv.h>
 #include <highgui.h>
 #include <stdio.h>
 #pragma comment( lib, "cv.lib" )
 #pragma comment( lib, "cxcore.lib" )
 #pragma comment( lib, "highgui.lib" )
 IplImage* org = 0;
 IplImage* img = 0;
 IplImage* tmp = 0;
 IplImage* dst = 0;
 void on_mouse( int event, int x, int y, int flags, void* ustc)
 {
     static CvPoint pre_pt = {-1,-1};
     static CvPoint cur_pt = {-1,-1};
     CvFont font;
     cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, CV_AA);
     char temp[16];

     if( event == CV_EVENT_LBUTTONDOWN )
     {
         cvCopy(org,img);
         sprintf(temp,"(%d,%d)",x,y);
         pre_pt = cvPoint(x,y);
         cvPutText(img,temp, pre_pt, &font, cvScalar(0,0, 0, 255));
         cvCircle( img, pre_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 );
         cvShowImage( "img", img );
         cvCopy(img,tmp);
     }
     else if( event == CV_EVENT_MOUSEMOVE && !(flags & CV_EVENT_FLAG_LBUTTON))
     {
         cvCopy(tmp,img);
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(img,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvShowImage( "img", img );
     }
     else if( event == CV_EVENT_MOUSEMOVE && (flags & CV_EVENT_FLAG_LBUTTON))
     {
         cvCopy(tmp,img);
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(img,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvRectangle(img, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, 8, 0 );
         cvShowImage( "img", img );
     }
     else if( event == CV_EVENT_LBUTTONUP )
     {
         cvCopy(tmp,img);
         sprintf(temp,"(%d,%d)",x,y);
         cur_pt = cvPoint(x,y);
         cvPutText(img,temp, cur_pt, &font, cvScalar(0,0, 0, 255));
         cvCircle( img, cur_pt, 3,cvScalar(255,0,0,0) ,CV_FILLED, CV_AA, 0 );
         cvRectangle( img, pre_pt, cur_pt, cvScalar(0,255,0,0), 1, 8, 0 );
         cvShowImage( "img", img );
         cvCopy(img,tmp);
         int width=abs(pre_pt.x-cur_pt.x);
         int height=abs(pre_pt.y-cur_pt.y);
         if(width==0 || height==0)
         {
             cvDestroyWindow("dst");
             return;
         }
         dst=cvCreateImage(cvSize(width,height),org->depth,org->nChannels);
         CvRect rect;
         if(pre_pt.x<cur_pt.x && pre_pt.y<cur_pt.y)
         {
             rect=cvRect(pre_pt.x,pre_pt.y,width,height);
         }
         else if(pre_pt.x>cur_pt.x && pre_pt.y<cur_pt.y)
         {
             rect=cvRect(cur_pt.x,pre_pt.y,width,height);
         }
         else if(pre_pt.x>cur_pt.x && pre_pt.y>cur_pt.y)
         {
             rect=cvRect(cur_pt.x,cur_pt.y,width,height);
         }
         else if(pre_pt.x<cur_pt.x && pre_pt.y>cur_pt.y)
         {
             rect=cvRect(pre_pt.x,cur_pt.y,width,height);
         }
         cvSetImageROI(org,rect);
         cvCopy(org,dst);
         cvResetImageROI(org);
         cvDestroyWindow("dst");
         cvNamedWindow("dst",1);
         cvShowImage("dst",dst);
         cvSaveImage("dst.jpg",dst);
     }
 }
 int main()
 {
     org=cvLoadImage("lena.jpg",1);
     img=cvCloneImage(org);
     tmp=cvCloneImage(org);
     cvNamedWindow("img",1);
     cvSetMouseCallback( "img", on_mouse, 0 );

     cvShowImage("img",img);
     cvWaitKey(0);
     cvDestroyAllWindows();
     cvReleaseImage(&org);
     cvReleaseImage(&img);
     cvReleaseImage(&tmp);
     cvReleaseImage(&dst);
     return 0;
 }

 

效果图如下