  Deep neural networks are increasingly used on mobile devices, where
computational resources are limited. In this paper we develop CondenseNet, a
novel network architecture with unprecedented efficiency. It combines dense
connectivity with a novel module called learned group convolution. The dense
connectivity facilitates feature re-use in the network, whereas learned group
convolutions remove connections between layers for which this feature re-use is
superfluous. At test time, our model can be implemented using standard group
convolutions, allowing for efficient computation in practice. Our experiments
show that CondenseNets are far more efficient than state-of-the-art compact
convolutional networks such as MobileNets and ShuffleNets.
