学步园

Refer from: http://blog.csdn.net/leaf_1007/article/details/23677805

基于帧间差分法进行升级的三帧差分法，不同的测试视频可以设置不同二值化阈值来增强效果。
根据实际情况进行形态学处理。

[cpp]
view plaincopy

1. #include <opencv2/highgui/highgui.hpp>  
2. #include <opencv2/imgproc/imgproc.hpp>  
3. #include <opencv2/core/core.hpp>  
4.   
5. #define threshold_diff1 25 //设置简单帧差法阈值  
6. #define threshold_diff2 25 //设置简单帧差法阈值  
7.   
8. using namespace cv;  
9. using namespace std;  
10.   
11. int main(int argc,unsigned char* argv[])  
12. {  
13.     Mat img_src1,img_src2,img_src3;//3帧法需要3帧图片  
14.     Mat img_dst,gray1,gray2,gray3;  
15.     Mat gray_diff1,gray_diff2;//存储2次相减的图片  
16.     Mat gray_diff11,gray_diff12;  
17.     Mat gray_diff21,gray_diff22;  
18.     Mat gray;//用来显示前景的  
19.     bool pause=false;  
20.   
21.     VideoCapture vido_file("test3.avi");//在这里改相应的文件名  
22.     namedWindow("foreground",0);  
23.     for (;;)  
24.     {  
25.         if(!false)  
26.         {  
27.             vido_file >>img_src1;  
28.             cvtColor(img_src1,gray1,CV_BGR2GRAY);  
29.           
30.             waitKey(33);  
31.             vido_file >>img_src2;  
32.             cvtColor(img_src2,gray2,CV_BGR2GRAY);  
33.             imshow("video_src",img_src2);//  
34.   
35.             waitKey(33);  
36.             vido_file >>img_src3;  
37.             cvtColor(img_src3,gray3,CV_BGR2GRAY);  
38.   
39.             Sobel(gray1,gray1,  CV_8U,1,0,3,0.4,128);  
40.             Sobel(gray2,gray2,  CV_8U,1,0,3,0.4,128);  
41.             Sobel(gray3,gray3,  CV_8U,1,0,3,0.4,128);  
42.   
43.             subtract(gray2,gray1,gray_diff11);//第二帧减第一帧  
44.             subtract(gray1,gray2,gray_diff12);  
45.             add(gray_diff11,gray_diff12,gray_diff1);  
46.             subtract(gray3,gray2,gray_diff21);//第三帧减第二帧  
47.             subtract(gray2,gray3,gray_diff22);  
48.             add(gray_diff21,gray_diff22,gray_diff2);  
49.   
50.             for(int i=0;i<gray_diff1.rows;i++)  
51.                 for(int j=0;j<gray_diff1.cols;j++)  
52.                 {  
53.                     if(abs(gray_diff1.at<unsigned char>(i,j))>=threshold_diff1)//这里模板参数一定要用unsigned char，否则就一直报错  
54.                         gray_diff1.at<unsigned char>(i,j)=255;            //第一次相减阈值处理  
55.                     else gray_diff1.at<unsigned char>(i,j)=0;  
56.   
57.                     if(abs(gray_diff2.at<unsigned char>(i,j))>=threshold_diff2)//第二次相减阈值处理  
58.                         gray_diff2.at<unsigned char>(i,j)=255;  
59.                     else gray_diff2.at<unsigned char>(i,j)=0;  
60.                 }  
61.             bitwise_and(gray_diff1,gray_diff2,gray);  
62.               
63.             dilate(gray,gray,Mat());erode(gray,gray,Mat());  
64.               
65.             imshow("foreground",gray);  
66.         }  
67.         if( cvWaitKey(33) >= 0 )  
68.         break;  
69.     }  
70.     return 0;  
71. }