OpenCV:初试牛刀-带滚动条的视频播放-2

#include<iostream>
#include<Windows.h>

#include<opencv2/highgui/highgui.hpp>
#include<opencv2/core/core.hpp>
using namespace cv;
using namespace std;
#pragma comment( linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"" )//隐藏console控制台

int curFrame = 0;
cv::VideoCapture v1;

void onTrackbarSlide(int pos,void*)
{
v1.set(CV_CAP_PROP_POS_FRAMES, pos);
}

int main()
{
namedWindow("Demo2", CV_WINDOW_AUTOSIZE | CV_WINDOW_FREERATIO);
v1.open("H:/斯卡布罗集市.avi");
if (!v1.isOpened())
{
cout << "Could not open " <<endl;
return -1;
}

Mat frame;
int frames = v1.get(CV_CAP_PROP_FRAME_COUNT);
createTrackbar("position:", "Demo2", &curFrame, frames, onTrackbarSlide);
while (1)
{
HWND hWnd = (HWND)cvGetWindowHandle("Demo2");
v1 >> frame;
if (frame.empty()||hWnd==NULL)break;//视频播放时点击窗口关闭按钮（即小叉号）关闭窗口
imshow("Demo2", frame);

if(waitKey(30)>0)break;
}
v1.release();
destroyWindow("Demo2");
}