BaSNet-pytorch

Pytorch Implementation of 'Background Suppression Network for Weakly-supervised Temporal Action Localization' (AAAI 2020)

Background Suppression Network for Weakly-supervised Temporal Action Localization
Pilhyeon Lee (Yonsei Univ.), Youngjung Uh (Clova AI, NAVER Corp.), Hyeran Byun (Yonsei Univ.)

Paper: https://arxiv.org/abs/1911.09963

Abstract: Weakly-supervised temporal action localization is a very challenging problem because frame-wise labels are not given in the training stage while the only hint is video-level labels: whether each video contains action frames of interest. Previous methods aggregate frame-level class scores to produce video-level prediction and learn from video-level action labels. This formulation does not fully model the problem in that background frames are forced to be misclassified as action classes to predict video-level labels accurately. In this paper, we design Background Suppression Network (BaS-Net) which introduces an auxiliary class for background and has a two-branch weight-sharing architecture with an asymmetrical training strategy. This enables BaS-Net to suppress activations from background frames to improve localization performance. Extensive experiments demonstrate the effectiveness of BaS-Net and its superiority over the state-of-the-art methods on the most popular benchmarks - THUMOS'14 and ActivityNet.

(2020/06/16) Our new model is available now!

Background Modeling via Uncertainty Estimation for Weakly-supervised Action Localization [Paper] [Code]

Prerequisites

Recommended Environment

• Python 3.5
• Pytorch 1.0
• Tensorflow 1.15 (for Tensorboard)

Depencencies

You can set up the environments by using $ pip3 install -r requirements.txt.

Data Preparation

1. Prepare THUMOS'14 dataset.

   • We excluded three test videos (270, 1292, 1496) as previous work did.

2. Extract features with two-stream I3D networks

   • We recommend extracting features using this repo.
   • For convenience, we provide the features we used. You can find them here.

3. Place the features inside the dataset folder.

   • Please ensure the data structure is as below.

├── dataset
   └── THUMOS14
       ├── gt.json
       ├── split_train.txt
       ├── split_test.txt
       └── features
           ├── train
               ├── rgb
                   ├── video_validation_0000051.npy
                   ├── video_validation_0000052.npy
                   └── ...
               └── flow
                   ├── video_validation_0000051.npy
                   ├── video_validation_0000052.npy
                   └── ...
           └── test
               ├── rgb
                   ├── video_test_0000004.npy
                   ├── video_test_0000006.npy
                   └── ...
               └── flow
                   ├── video_test_0000004.npy
                   ├── video_test_0000006.npy
                   └── ...

Usage

Running

You can easily train and evaluate BaS-Net by running the script below.

If you want to try other training options, please refer to options.py.

$ bash run.sh

Evaulation

The pre-trained model can be found here. You can evaluate the model by running the command below.

$ bash run_eval.sh

References

We referenced the repos below for the code.

• STPN
• ActivityNet

Citation

If you find this code useful, please cite our paper.

@inproceedings{lee2020BaS-Net,
  title={Background Suppression Network for Weakly-supervised Temporal Action Localization},
  author={Lee, Pilhyeon and Uh, Youngjung and Byun, Hyeran},
  booktitle={The 34th AAAI Conference on Artificial Intelligence},
  pages={11320--11327},
  year={2020}
}

Contact

If you have any question or comment, please contact the first author of the paper - Pilhyeon Lee ([email protected]).