Paraphrasing Complex Network: Network Compression via Factor Transfer

Deep neural networks (DNN) have recently shown promising performances in various areas. Although DNNs are very powerful, a large number of network parameters requires substantial storage and memory bandwidth which hinders them from being applied to actual embedded systems. Many researchers have sought ways of model compression to reduce the size of a network with minimal performance degradation. Among them, a method called knowledge transfer is to train the student network with a stronger teacher network. In this paper, we propose a method to overcome the limitations of conventional knowledge transfer methods and improve the performance of a student network. An auto-encoder is used in an unsupervised manner to extract compact factors which are defined as compressed feature maps of the teacher network. When using the factors to train the student network, we observed that the performance of the student network becomes better than the ones with other conventional knowledge transfer methods because factors contain paraphrased compact information of the teacher network that is easy for the student network to understand.