Opencv讀取並獲取視頻屬性

opencv中通過VideoCaptrue類對視頻進行讀取操作以及調用攝像頭.常用的操作如下:

1、常用構造函數

1.VideoCapture類的構造函數：
C++: VideoCapture::VideoCapture()
C++: VideoCapture::VideoCapture(const string& filename)
C++: VideoCapture::VideoCapture(int device)

2、判斷是否打開

cap.isOpened()

3、獲取視頻相關屬性

cout << "視頻相關信息如下" << endl;
cout << "寬度：" << cap.get(CV_CAP_PROP_FRAME_WIDTH) << endl;
cout << "高度：" << cap.get(CV_CAP_PROP_FRAME_HEIGHT) << endl;

cout << "總幀數：" << cap.get(CV_CAP_PROP_FRAME_COUNT) << endl;
cout << "幀率（fps）：" << cap.get(CV_CAP_PROP_FPS) << endl;

4、逐幀讀取

Mat frame;

cap >> frame;

5、判斷是否完畢

frame.empty()

6、顯示視頻

imshow("readvideo", frame);

include <opencv2\opencv.hpp>
#include <iostream>
using namespace std;
using namespace cv;
int main()
{
    cout <<CV_VERSION << endl;
    VideoCapture cap("c://dev//res//out.avi");
    if (!cap.isOpened())
    {
        cout << "視頻文件打開失敗" << endl;
    }
    cout << "視頻相關信息如下" << endl;
    cout << "寬度：" << cap.get(CV_CAP_PROP_FRAME_WIDTH) << endl;
    cout << "高度：" << cap.get(CV_CAP_PROP_FRAME_HEIGHT) << endl;
    cout << "總幀數：" << cap.get(CV_CAP_PROP_FRAME_COUNT) << endl;
    cout << "幀率（fps）：" << cap.get(CV_CAP_PROP_FPS) << endl;

    Mat frame;
    while (1)
    {
        cap >> frame;
        if (frame.empty())
        {
            break;
        }
        imshow("readvideo", frame);
        waitKey(20);//win10 vs2015返回值-1
    }
    getchar();
    return 0;