This repository contains the code (in PyTorch) for "CondenseNet: An Efficient DenseNet using Learned Group Convolutions" paper by Gao Huang, Shichen Liu, Laurens van der Maaten and Kilian Weinberger (* Authors contributed equally).


If you find our project useful in your research, please consider citing:

  title={Condensenet: An efficient densenet using learned group convolutions},
  author={Huang, Gao and Liu, Shichen and Van der Maaten, Laurens and Weinberger, Kilian Q},
  booktitle={Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition},


  1. Introduction
  2. Usage
  3. Results
  4. Discussions
  5. Contacts


CondenseNet is a novel, computationally efficient convolutional network architecture. It combines dense connectivity between layers with a mechanism to remove unused connections. 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 grouped convolutions —- allowing for efficient computation in practice. Our experiments demonstrate that CondenseNets are much more efficient than other compact convolutional networks such as MobileNets and ShuffleNets.

Figure 1: Learned Group Convolution with G=C=3.

![]( =480x)

Figure 2: CondenseNets with Fully Dense Connectivity and Increasing Growth Rate.




As an example, use the following command to train a CondenseNet on ImageNet

python --model condensenet -b 256 -j 20 /PATH/TO/IMAGENET \
--stages 4-6-8-10-8 --growth 8-16-32-64-128 --gpu 0,1,2,3,4,5,6,7 --resume

As another example, use the following command to train a CondenseNet on CIFAR-10

python --model condensenet -b 64 -j 12 cifar10 \
--stages 14-14-14 --growth 8-16-32 --gpu 0 --resume


We take the ImageNet model trained above as an example.

To evaluate the trained model, use evaluate to evaluate from the default checkpoint directory:

python --model condensenet -b 64 -j 20 /PATH/TO/IMAGENET \
--stages 4-6-8-10-8 --growth 8-16-32-64-128 --gpu 0 --resume \

or use evaluate-from to evaluate from an arbitrary path:

python --model condensenet -b 64 -j 20 /PATH/TO/IMAGENET \
--stages 4-6-8-10-8 --growth 8-16-32-64-128 --gpu 0 --resume \
--evaluate-from /PATH/TO/BEST/MODEL

Note that these models are still the large models. To convert the model to group-convolution version as described in the paper, use the convert-from function:

python --model condensenet -b 64 -j 20 /PATH/TO/IMAGENET \
--stages 4-6-8-10-8 --growth 8-16-32-64-128 --gpu 0 --resume \
--convert-from /PATH/TO/BEST/MODEL

Finally, to directly load from a converted model (that is, a CondenseNet), use a converted model file in combination with the evaluate-from option:

python --model condensenet_converted -b 64 -j 20 /PATH/TO/IMAGENET \
--stages 4-6-8-10-8 --growth 8-16-32-64-128 --gpu 0 --resume \
--evaluate-from /PATH/TO/CONVERTED/MODEL

Other Options

We also include DenseNet implementation in this repository.
For more examples of usage, please refer to
For detailed options, please python --help


Results on ImageNet

Model FLOPs Params Top-1 Err. Top-5 Err. Pytorch Model
CondenseNet-74 (C=G=4) 529M 4.8M 26.2 8.3 Download (18.69M)
CondenseNet-74 (C=G=8) 274M 2.9M 29.0 10.0 Download (11.68M)

Results on CIFAR

Model FLOPs Params CIFAR-10 CIFAR-100
CondenseNet-50 28.6M 0.22M 6.22 -
CondenseNet-74 51.9M 0.41M 5.28 -
CondenseNet-86 65.8M 0.52M 5.06 23.64
CondenseNet-98 81.3M 0.65M 4.83 -
CondenseNet-110 98.2M 0.79M 4.63 -
CondenseNet-122 116.7M 0.95M 4.48 -
CondenseNet-182* 513M 4.2M 3.76 18.47

(* trained 600 epochs)

Inference time on ARM platform

Model FLOPs Top-1 Time(s)
VGG-16 15,300M 28.5 354
ResNet-18 1,818M 30.2 8.14
1.0 MobileNet-224 569M 29.4 1.96
CondenseNet-74 (C=G=4) 529M 26.2 1.89
CondenseNet-74 (C=G=8) 274M 29.0 0.99


[email protected]
[email protected]