Face detection: face and landmark drawing incorrectly with Front camera on Android devices

[ngtrphuong]

Thanks a lot for this great and powerful widget,
I have the project needs this feature (face detection) and luckily I found this plug-in,
Everything works flawlessly except the Android Front camera: the rectangle draw on detected face is drawing incorrectly, see snapshots below. I've already fixed this by swapping the rectangle by 180 in vertical order. Not sure this is the optimized codes, let me know if any,

Moreover, I also add one more for loop to detect multiple faces instead of just only one face as your example,