An All-In-One Convolutional Neural Network for Face Analysis
  We present a multi-purpose algorithm for simultaneous face detection, face alignment, pose estimation, gender recognition, smile detection, age estimation and face recognition using a single deep convolutional neural network (CNN). The proposed method employs a multi-task learning framework that regularizes the shared parameters of CNN and builds a synergy among different domains and tasks. Extensive experiments show that the network has a better understanding of face and achieves state-of-the-art result for most of these tasks. 
Rajeev Ranjan, Swami Sankaranarayanan, Carlos D. Castillo and Rama   Chellappa
cs.CV