SEED

Implementations for the ICLR-2021 paper: SEED: Self-supervised Distillation For Visual Representation.

@Article{fang2020seed,
  author  = {Fang, Zhiyuan and Wang, Jianfeng and Wang, Lijuan and Zhang, Lei and Yang, Yezhou and Liu, Zicheng},
  title   = {SEED: Self-supervised Distillation For Visual Representation},
  journal = {International Conference on Learning Representations},
  year    = {2021},
}

Introduction

This paper is concerned with self-supervised learning for small models. The problem is motivated by our empirical studies that while the widely used contrastive self-supervised learning method has shown great progress on large model training, it does not work well for small models. To address this problem, we propose a new learning paradigm, named SElf-SupErvised Distillation (SEED), where we leverage a larger network (as Teacher) to transfer its representational knowledge into a smaller architecture (as Student) in a self-supervised fashion. Instead of directly learning from unlabeled data, we train a student encoder to mimic the similarity score distribution inferred by a teacher over a set of instances. We show that SEED dramatically boosts the performance of small networks on downstream tasks. Compared with self-supervised baselines, SEED improves the top-1 accuracy from 42.2% to 67.6% on EfficientNet-B0 and from 36.3% to 68.2% on MobileNetV3-Large on the ImageNet-1k dataset. SEED improves the ResNet-50 from 67.4% to 74.3% from the previous MoCo-V2 baseline.

Preperation

Note: This repository does not contain the ImageNet dataset building, please refer to MoCo-V2 for the enviromental setting & dataset preparation. Be careful if you use FaceBook's ImageNet dataset implementation as the provided dataloader here is to handle TSV ImageNet source.

Self-Supervised Distillation Training

SWAV's 400_ep ResNet-50 model as Teacher architecture for a Student EfficientNet-b1 model with multi-view strategies. Place the pre-trained checkpoint in ./output directory. Remember to change the parameter name in the checkpoint as some module provided by SimCLR, MoCo-V2 and SWAV are inconsistent with regular PyTorch implementations. Here we provide the pre-trained SWAV/MoCo-V2/SimCLR Pre-trained checkpoints, but all credits belong to them.

To conduct the training one GPU on single Node using Distributed Training:

python -m torch.distributed.launch --nproc_per_node=1 main_small-patch.py \
       -a efficientnet_b1 \
       -k resnet50 \
       --teacher_ssl swav \
       --distill ./output/swav_400ep_pretrain.pth.tar \
       --lr 0.03 \
       --batch-size 16 \
       --temp 0.2 \
       --workers 4 
       --output ./output \
       --data [your TSV imagenet-folder with train folders]

Conduct linear evaluations on ImageNet-val split:

python -m torch.distributed.launch --nproc_per_node=1  main_lincls.py \
       -a efficientnet_b0 \
       --lr 30 \
       --batch-size 32 \
       --output ./output \ 
       [your TSV imagenet-folder with val folders]

Checkpoints by SEED

Here we provide some pre-trained checkpoints after distillation by SEED. Note: the 800 epcohs one are trained with small-view strategies and have better performances.

Glance of the Performances

ImageNet-1k test accuracy (%) using KNN and linear classification for multiple students and MoCov2 pre-trained deeper teacher architectures. ✗ denotes MoCo-V2 self-supervised learning baselines before distillation. * indicates using a deeper teacher encoder pre-trained by SWAV, where additional small-patches are also utilized during distillation and trained for 800 epochs. K denotes Top-1 accuracy using KNN. T-1 and T-5 denote Top-1 and Top-5 accuracy using linear evaluation. First column shows Top-1 Acc. of Teacher network. First row shows the supervised performances of student networks.

Acknowledge

This implementation is largely originated from: MoCo-V2. Thanks SWAV and SimCLR for the pre-trained SSL checkpoints.

This work is done jointly with ASU-APG lab and Microsoft Azure-Florence Group. Thanks my collaborators.

License

SEED is released under the MIT license.