https://qooah.com/2012/04/03/cydia-camera-grabber%e4%bb%a4ios-5-0%e4%b9%9f%e6%9c%895-1%e7%9a%84%e9%8e%96%e5%b1%8f%e7%9b%b8%e6%a9%9f%e5%8a%9f%e8%83%bd-2/