OpenCV图像处理->鼠标移动区域放大

调用OpenCV函数里面的鼠标响应函数：

	cvSetMouseCallback( "img", on_mouse, 0 );

鼠标响应具体实现的函数：

int foo=100;//调节窗口大小，也称为比例系数。 void on_mouse( int event, int x, int y, int flags, void* ustc) { 	if( event == CV_EVENT_MOUSEMOVE && !(flags & CV_EVENT_FLAG_LBUTTON)) 	{ 		cvCopy(org,img); 		CvPoint p0; 		CvPoint p1; 		if(x<foo) 		{ 			if(y<foo) 			{ 				p0=cvPoint(0,0); 				p1=cvPoint(2*foo,2*foo); 			} 			else if(y>img->height-foo) 			{  				p0=cvPoint(0,img->height-2*foo); 				p1=cvPoint(2*foo,img->height); 			} 			else 			{ 				p0=cvPoint(0,y-foo); 				p1=cvPoint(2*foo,y+foo); 			} 		} 		else if(x>img->width-foo) 		{ 			if(y<foo) 			{ 				p0=cvPoint(img->width-2*foo,0); 				p1=cvPoint(img->width,2*foo); 			} 			else if(y>img->height-foo) 			{  				p0=cvPoint(img->width-2*foo,img->height-2*foo); 				p1=cvPoint(img->width,img->height); 			} 			else 			{ 				p0=cvPoint(img->width-2*foo,y-foo); 				p1=cvPoint(img->width,y+foo); 			} 		} 		else 		{ 			if(y<foo) 			{ 				p0=cvPoint(x-foo,0); 				p1=cvPoint(x+foo,2*foo); 			} 			else if(y>img->height-foo) 			{  				p0=cvPoint(x-foo,img->height-2*foo); 				p1=cvPoint(x+foo,img->height); 			} 			else 			{ 				p0=cvPoint(x-foo,y-foo); 				p1=cvPoint(x+foo,y+foo); 			} 		} 		cvRectangle(img,p0,p1,CV_RGB(0,255,0)); 		cvSetImageROI(org,cvRect(p0.x,p0.y,p1.x-p0.x,p1.y-p0.y));//设置感兴趣区域 		cvResize(org,dst);//大小重置 		cvResetImageROI(org); 		cvShowImage( "img", img ); 		cvShowImage("dst",dst); 	} }