A deep neural network compression algorithm based on knowledge transfer for edge devices

Abstract

The computation and storage capacity of the edge device are limited, which seriously restrict the application of deep neural network in the device. Toward to the intelligent application of the edge device, we introduce the deep neural network compression algorithm based on knowledge transfer, a three-stage pipeline: lightweight, multi-level knowledge transfer and pruning that reduce the network depth, parameter and operation complexity of the deep learning neural networks. We lighten the neural networks by using a global average pooling layer instead of a fully connected layer and replacing a standard convolution with separable convolutions. Next, the multi-level knowledge transfer minimizes the difference between the output of the ”student network” and the ”teacher network” in the middle and logits layer, increasing the supervised information when training the ”student network”. Lastly, we prune the network by cutting off the unimportant convolution kernels with a global iterative pruning strategy. The experiment results show that the proposed method improve the efficiency up to 30% than the knowledge distillation method in reducing the loss of classification performance. Benchmarked on GPU (Graphics Processing Unit) server, Raspberry Pi 3 and Cambricon-1A, the parameters of the compressed network after using our knowledge transfer and pruning method have achieved more than 49.5 times compression and the time efficiency of a single feedforward operation has been improved more than 3.2 times.