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>

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 };                  //初始化鼠标窗口的选择的坐标
	CvFont font;
	cvInitFont(&font, CV_FONT_HERSHEY_SIMPLEX, 0.5, 0.5, 0, 1, CV_AA);                 //表示书写文字的操作
	char temp[16];

	if (event == CV_EVENT_LBUTTONDOWN)                                           //当鼠标按下时，输出当前的坐标位置，用圆点表示
	{
		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))                    //当鼠标移动，并且向左边拖拽的时候，输出鼠标点的位置信息
	{
		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);                                                                              
	}                                                                                                       //当鼠标移动，并且向左边拖拽的时候，画出拖拽的矩形
	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);                                                                                  //当鼠标按键放开时，画出鼠标点的坐标，并且画出鼠标画出的矩形
		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;
		}                                                                                                           //查看鼠标画出的矩形的大小，并用改大小表示这一区域的图像
		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);                                                                 //取图像感兴趣区域的图像，rect里的图像
		cvCopy(org, dst);      
		cvResetImageROI(org);
		cvDestroyWindow("dst");
		cvNamedWindow("dst", 1);
		cvShowImage("dst", dst);
		cvSaveImage("dst.jpg", dst);
	}
}
int main()
{
	org = cvLoadImage("D:6.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





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

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#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