简单帧差法

代码来自：http://www.cnblogs.com/tornadomeet/archive/2012/05/01/2477629.html
 1 #include <string>
 2 #include <iostream>
 3 #include <stdio.h>
 4 #include <fstream>
 5 #include<math.h>
 6 
 7 #include <opencv2opencv.hpp>
 8 #include <opencv2highguihighgui.hpp>
 9 #include <opencv2imgprocimgproc.hpp>
10 #include <opencv2corecore.hpp>
11 
12 
13 #define threshold_diff 18 //设置简单帧差法阈值
14 
15 using namespace cv;
16 using namespace std;
17 
18 int main(int argc, unsigned char* argv[])
19 {
20     Mat img_src1, img_src2, img_dst, gray1, gray2, gray_diff;
21     bool pause = false;
22 
23     VideoCapture vido_file("a.avi");//在这里改相应的文件名
24     namedWindow("foreground", 0);
25     for (;;)
26     {
27         if (!pause )
28         {
29             vido_file >> img_src1;        //因为视频文件帧数已经固定了，所以每次到这句语句都是读取相邻的帧数，没到时间视频并不向前走
30             if (img_src1.empty())        //【】没有这个判断的话，视频播放完了会有内存溢出错误，所以播完就直接break！
31                 break;
32             //GaussianBlur(img_src1, img_src1, Size(3, 3), 60);
33             cvtColor(img_src1, gray1, CV_BGR2GRAY);
34             imshow("video_src", img_src1);//可以事先不用新建一个窗口
35             waitKey(5);
36 
37             vido_file >> img_src2;
38             //GaussianBlur(img_src2, img_src2, Size(3, 3), 60);
39             cvtColor(img_src2, gray2, CV_BGR2GRAY);
40             imshow("video_src", img_src2);//可以事先不用新建一个窗口
41 
42             waitKey(5);
43             subtract(gray1, gray2, gray_diff);
44             GaussianBlur(gray_diff, gray_diff, Size(3, 3), 0,0);
45             for (int i = 0; i<gray_diff.rows; i++)
46             for (int j = 0; j<gray_diff.cols; j++)
47             if (abs(gray_diff.at<unsigned char>(i, j)) >= threshold_diff)//这里模板参数一定要用unsigned char，否则就一直报错
48                 gray_diff.at<unsigned char>(i, j) = 255;
49             else gray_diff.at<unsigned char>(i, j) = 0;
50 
51             imshow("foreground", gray_diff);
52         }
53         char c = (char)waitKey(10);
54         if (c == 27)
55         {
56             break;
57         }
58         if (c == ' ')
59             pause = !pause;
60     }
61     return 0;
62 }
效果：