Opencv帧差法

#define threshold_diff1 10 //设置简单帧差法阈值
#define threshold_diff2 10 //设置简单帧差法阈值
int main(int argc,unsigned char* argv[])
{	
   Mat img_src1,img_src2,img_src3;//3帧法须要3帧图片
   Mat img_dst,gray1,gray2,gray3;
   Mat gray_diff1,gray_diff2;//存储2次相减的图片
   Mat gray;//用来显示前景的
   bool pause=false;
   VideoCapture vido_file("1.flv");//在这里改相应的文件名,输入也能够为摄像头设备  输入形式为 '0'
   namedWindow("foreground",0);
   for (;;)	
   {		
      if(!false)	
	{		
	  vido_file >>img_src1;	
        cvtColor(img_src1,gray1,CV_BGR2GRAY);	
	waitKey(5);		
	vido_file >>img_src2;	
	cvtColor(img_src2,gray2,CV_BGR2GRAY);	
	imshow("video_src",img_src2);//	
	waitKey(5);			
        vido_file >>img_src3;	
	cvtColor(img_src3,gray3,CV_BGR2GRAY);	
	subtract(gray2,gray1,gray_diff1);//第二帧减第一帧	
	subtract(gray3,gray2,gray_diff2);//第三帧减第二帧	
	for(int i=0;i<gray_diff1.rows;i++)		
	 for(int j=0;j<gray_diff1.cols;j++)	
	   {			
		if(abs(gray_diff1.at<unsigned char>(i,j))>=threshold_diff1)//这里模板参数必定要用unsigned char，不然就一直报错						
               gray_diff1.at<unsigned char>(i,j)=255;            //第一次相减阈值处理				else gray_diff1.at<unsigned char>(i,j)=0;					                if(abs(gray_diff2.at<unsigned char>(i,j))>=threshold_diff2)//第二次相减阈值处理			gray_diff2.at<unsigned char>(i,j)=255;	
		else gray_diff2.at<unsigned char>(i,j)=0;	
	}				
        bitwise_and(gray_diff1,gray_diff2,gray);	
	}	
	char c=(char)waitKey(10);
		if (c==27)	
	{		
	break;    	
	}		
       if(c== ' ')	
		pause=!pause;
	}	
return 0;
}