我们需要分别检测两个眼睛 Left eye points: (36, 37, 38, 39, 40, 41)
Right eye points: (42, 43, 44, 45, 46, 47)
当我们的眼睛向左看时键盘左半部分显示，
当我们的眼睛向又看时键盘的右半部分显示，
The idea is to see a keyboard on the screen, light up each key every second or so and when the key we’re insterested in is on,
simply we close our eyes.
If we consider that the keyboard has 26 letters of the alphabet, plus we need the space and some other key,
just to run through all the keys lighting up each for one second, it will take half a mintue each time.
The idea is to devide the keyboard in two parts. If we look on the left side only the left part of the keyboard will be activated,
while if we look on the right side only the letter on the right part of the keyboard will light up
闭眼之前已经选中，闭眼是为了激活