Face Detection, Key Point Detection, and Mask Detection on Android with One Line of Code

This paper introduces the method of implementing face detection, key point detection, and mask detection in Android applications using Paddle Lite. The core code is only one line: calling `FaceDetectionUtil.getInstance().predictImage(bitmap)` can complete multiple functions. Behind this line of code, it involves model training and compilation, including face detection (`pyramidbox.nb`), face key point detection (`facekeypoints.nb`), and mask classification (