在arm下进行视频实时采集和显示，使用V4L2与Qtimer结合的QT程序。-Under the arm real-time video capture and display, combined with V4L2 and Qtimer QT program.

QT实现时钟，界面简单，利用QTIMER实现，界面比较漂亮-QT for clock, the clock electronic clock QT, QT to achieve clock electronic clock, electronic clock QT achieve clock, electronic clock

qt定时器的使用，通过QT的定时器，进行数码管的倒计时(The use of the QT timer)