1 #include <opencv2/core/core.hpp>
2 #include <opencv2/highgui/highgui.hpp>
3 #include <opencv2/imgproc/imgproc.hpp>
4 #include <iostream>
5
6 using namespace std;
7 using namespace cv;
8
9 int main()
10 {
11 //打开视频文件：其实就是建立一个VideoCapture结构
12 VideoCapture capture("D:/videos/PetsD2TeC2.avi");
13 //检测是否正常打开:成功打开时，isOpened返回ture
14 if(!capture.isOpened())
15 cout<<"fail to open!"<<endl;
16 //获取整个帧数
17 long totalFrameNumber = capture.get(CV_CAP_PROP_FRAME_COUNT);
18 cout<<"整个视频共"<<totalFrameNumber<<"帧"<<endl;
19
20
21 //设置开始帧()
22 long frameToStart = 300;
23 capture.set( CV_CAP_PROP_POS_FRAMES,frameToStart);
24 cout<<"从第"<<frameToStart<<"帧开始读"<<endl;
25
26
27 //设置结束帧
28 int frameToStop = 400;
29
30 if(frameToStop < frameToStart)
31 {
32 cout<<"结束帧小于开始帧，程序错误，即将退出！"<<endl;
33 return -1;
34 }
35 else
36 {
37 cout<<"结束帧为：第"<<frameToStop<<"帧"<<endl;
38 }
39
40
41 //获取帧率
42 double rate = capture.get(CV_CAP_PROP_FPS);
43 cout<<"帧率为:"<<rate<<endl;
44
45
46
47 //定义一个用来控制读取视频循环结束的变量
48 bool stop = false;
49 //承载每一帧的图像
50 Mat frame;
51 //显示每一帧的窗口
52 namedWindow("Extracted frame");
53 //两帧间的间隔时间:
54 //int delay = 1000/rate;
55 int delay = 1000/rate;
56
57
58 //利用while循环读取帧
59 //currentFrame是在循环体中控制读取到指定的帧后循环结束的变量
60 long currentFrame = frameToStart;
61
62
63 //滤波器的核
64 int kernel_size = 3;
65 Mat kernel = Mat::ones(kernel_size,kernel_size,CV_32F)/(float)(kernel_size*kernel_size);
66
67 while(!stop)
68 {
69 //读取下一帧
70 if(!capture.read(frame))
71 {
72 cout<<"读取视频失败"<<endl;
73 return -1;
74 }
75
76 //这里加滤波程序
77 imshow("Extracted frame",frame);
78 filter2D(frame,frame,-1,kernel);
79
80 imshow("after filter",frame);
81 cout<<"正在读取第"<<currentFrame<<"帧"<<endl;
82 //waitKey(int delay=0)当delay ≤ 0时会永远等待；当delay>0时会等待delay毫秒
83 //当时间结束前没有按键按下时，返回值为-1；否则返回按键
84
85
86 int c = waitKey(delay);
87 //按下ESC或者到达指定的结束帧后退出读取视频
88 if((char) c == 27 || currentFrame > frameToStop)
89 {
90 stop = true;
91 }
92 //按下按键后会停留在当前帧，等待下一次按键
93 if( c >= 0)
94 {
95 waitKey(0);
96 }
97 currentFrame++;
98
99 }
100 //关闭视频文件
101 capture.release();
102 waitKey(0);
103 return 0;
104 }
