Few-shot

Few-shot is a lightweight library that implements state-of-the-art few-shot learning algorithms.

In the current version, the following algorithms are included. We welcome other researchers to contribute to this framework.

• Neg-Cosine/Neg-Softmax: Negative Margin Matters: Understanding Margin in Few-shot Classification.
• MatchingNet: Matching Networks for One Shot Learning.
• ProtoNet: Prototypical networks for few-shot learning.
• RelationNet: Learning to compare: Relation network for few-shot learning.
• Baseline/Baseline++: A closer look at few-shot classification.

Main Results

The few-shot classification accuracy on the novel classes with ResNet-18 as the backbone is listed bellowing:

Method	Mini-ImageNet 1 - shot	Mini-ImageNet 5 - shot	CUB 1 - shot	CUB 5 - shot	Mini -> CUB 5-shot
MatchingNet	52.91+-0.88	68.88+-0.69	72.36+-0.90	83.64+-0.60	53.07+-0.74
MatchingNet (Ours)	58.84+-0.80	72.14+-0.67	73.38+-0.89	85.10+-0.52	59.18+-0.69
ProtoNet	54.16+-0.82	73.68+-0.65	71.88+-0.91	87.42+-0.48	62.02+-0.70
ProtoNet (Ours)	57.35+-0.81	75.80+-0.64	73.44+-0.84	88.29+-0.48	61.43+-0.78
RelationNet	52.48+-0.86	69.83+-0.68	67.59+-1.02	82.75+-0.58	57.71+-0.73
RelationNet (Ours)	54.11+-0.81	70.13+-0.70	70.56+-0.94	84.61+-0.56	54.16+-0.70
Baseline	51.75+-0.80	74.27+-0.63	65.51+-0.87	82.85+-0.55	65.57+-0.70
Baseline (Ours)	52.41+-0.77	74.82+-0.68	63.89+-0.87	82.69+-0.55	64.56+-0.73
Baseline++	51.87+-0.77	75.68+-0.63	67.02+-0.90	83.58+-0.54	62.04+-0.76
Baseline++ (Ours)	55.89+-0.82	76.99+-0.61	70.93+-0.89	88.64+-0.47	66.08+-0.69
Neg-Sofmax (Ours)	59.02+-0.81	78.80+-0.61	71.48+-0.83	87.30+-0.48	69.30+-0.73
Neg-Cosine (Ours)	62.33+-0.82	80.94+-0.59	72.66+-0.85	89.40+-0.43	67.03+-0.76

Notes:

• The results without Ours in the above comes from A closer look at few-shot classification.
• Mini -> CUB stands for mini-ImageNet -> CUB

The above results shows that our implementation gets much higher few-shot accuracies than orginal implementation in almost all algorithms and datasets.

You can download some pre-trained model checkpoints of resnet-18 from OneDrive.

Getting started

Environment

• Anaconda with python >= 3.6
• pytorch=1.2.0, torchvison, cuda=9.2
• others: pip install yacs termcolor

Datasets

CUB

• Change directory to ./data/CUB
• run bash ./download_CUB.sh

mini-ImageNet

• Change directory to ./data/miniImagenet
• run bash ./download_miniImagenet.sh

(WARNING: This would download the 155G ImageNet dataset. You can comment out the corresponded line 5-6 in download_miniImagenet.sh if you already have one.)

mini-ImageNet->CUB

• Finish preparation for CUB and mini-ImageNet, and you are done!

Train and eval

Run the following commands to train and evaluate:

python main.py --config [CONFIGFILENAME] \
    method.backbone [BACKBONE] \
    method.image_size [IMAGESIZE] \
    method.metric [Metric] \
    [OPTIONARG]

For additional options, please refer to ./few-shot/config.py.

We have also provided some scripts to reproduce the results in the table. Please check ./scripts for details.

References

This algorithm library is extended from https://github.com/bl0/negative-margin.few-shot, which builds upon several existing publicly available code:

• Framework, Backbone, Method: Closer Look at Few Shot https://github.com/wyharveychen/CloserLookFewShot
• Backbone(resnet12): MetaOpt https://github.com/kjunelee/MetaOptNet
• Backbone(wrn_28_10): S2M2_R https://github.com/nupurkmr9/S2M2_fewshot