opencv录制视频

使用笔记本的摄像头录制视频，并保存为avi格式。

参考：官方例程

#include "opencv2/opencv.hpp"
#include 

using namespace std;
using namespace cv;

int main() {

	// Create a VideoCapture object and use camera to capture the video
	VideoCapture cap(0);

	// Check if camera opened successfully
	if (!cap.isOpened())
	{
		cout << "Error opening video stream" << endl;
		return -1;
	}

	// Default resolution of the frame is obtained.The default resolution is system dependent. 
	int frame_width = cap.get(CV_CAP_PROP_FRAME_WIDTH);
	int frame_height = cap.get(CV_CAP_PROP_FRAME_HEIGHT);

	// Define the codec and create VideoWriter object.The output is stored in 'outcpp.avi' file. 
	VideoWriter video("outcpp.avi", CV_FOURCC('M', 'J', 'P', 'G'), 25, Size(frame_width, frame_height));
	while (1)
	{
		Mat frame;

		// Capture frame-by-frame 
		cap >> frame;

		// If the frame is empty, break immediately
		if (frame.empty())
			break;

		// Write the frame into the file 'outcpp.avi'
		video.write(frame);

		// Display the resulting frame    
		imshow("Frame", frame);

		// Press  ESC on keyboard to  exit   按ESC 推出录制
		char c = (char)waitKey(1);
		if (c == 27)
			break;
	}

	// When everything done, release the video capture and write object
	cap.release();
	video.release();

	// Closes all the windows
	destroyAllWindows();
	return 0;
}