opencv3 采集摄像头的画面canny化，或者读取视频

#include<opencv2/opencv.hpp>
#include<opencv2\opencv.hpp>
using namespace cv;

void main()
{
VideoCapture capture(0);//("C:\\Users\\Administrator\\Desktop\\工作\\testv\\carchase.mpg");
Mat edges;
while(1)
{
Mat frame;
capture>>frame;
cvtColor(frame,edges,CV_BGR2GRAY);
blur(edges,edges,Size(7,7));
Canny(edges,edges,0,30,3);
imshow("被canny后的视频",edges);
waitKey(25);
}
}