OPENCV学习笔记1-9_视频读取

#include <iostream>
#include "opencv2/opencv.hpp"
using namespace std;
using namespace cv;
int main( int argc, char** argv )
{
    /* VideoCapture cap(0);               //open the default camera */
    VideoCapture cap( "test.flv" );
    if ( !cap.isOpened() )
    {
        cerr << "Can not open a camera or file." << endl;
        return(-1);
    }
    Mat edges;
    namedWindow( "edges", 1 );
    namedWindow( "frame", 1 );
    for (;; )
    {
        Mat frame;
        cap >> frame;                     //get a new frame from cap
        if ( frame.empty() )
            break;
        imshow( "frame", frame );
        cvtColor( frame, edges, CV_BGR2GRAY );
        Canny( edges, edges, 0, 30, 3 );
        imshow( "edges", edges );
        if ( waitKey( 30 ) >= 0 )
            break;
    }
    /* the camera will be deinitialized automatically in VideoCapture destructor */
    return(0);
}