I. INTRODUCTION
Face alignment, also known as facial landmarks prediction, gets at the task of calculating the coordinates of several predefined points on a facial image, including eyes, nose, mouth, chin, etc. As shown in [1], [2], [3], accurate face alignment improves the performance of face verification system. Moreover, face alignment becomes the most pivotal component in many other facial analysis assignments, e.g. facial expression classification [4], [5] and 3D face modeling [6], [7]. In the past decades, many researches and algorithms have been developed for face alignment, it remains a challenging task, especially when the faces suffer from the huge variations caused by arbitrary pose and partial occlusions.