Content-Debiased FVD for Evaluating Video Generation Models

Project Page | Documentation | Paper

FVD is observed to favor the quality of individual frames over realistic motions. We verify this with quantitative measurement. We show that the bias can be attributed to the features extracted from a supervised video classifier trained on the content-biased dataset and using features from large-scale unsupervised models can mitigate the bias. This repo contains code tookit for easily computing FVDs with different pre-trained models. Please refer to out project page or paper for more details about the analysis.

On the Content Bias in Fréchet Video Distance
Songwei Ge, Aniruddha Mahapatra, Gaurav Parmar, Jun-Yan Zhu, Jia-Bin Huang
UMD, CMU, Adobe
CVPR 2024

Quickstart

We provide a simple interface to compute FVD scores between two sets of videos that can be adapted to different scenarios. You could install the library through pip:

pip install cd-fvd

You may choose to download some example UCF-101 videos to test the code via:

bash cdfvd/download_example_videos.sh

The following code snippet demonstrates how to compute FVD scores between a folder of videos and precomputed statistics.

from cdfvd import fvd
evaluator = fvd.cdfvd('videomae', ckpt_path=None)
evaluator.load_videos('ucf101', data_type='stats_pkl', resolution=128, sequence_length=16)
evaluator.compute_fake_stats(evaluator.load_videos('./example_videos/', data_type='video_folder'))
score = evaluator.compute_fvd_from_stats()

Please refer to the documentation for more detailed instructions on the usage.

Note: By default n_fake=2048. If n_fake is greater than number of videos in path/to/fakevideos/ folder, then same videos will be resampled n_fake times. If this is not the desired effect, please use custom value of n_fake of set n_fake='full' to use all videos in path/to/fakevideos/ without repetition.

Precomputed Datasets

We provide precomputed statistics for the following datasets.

Dataset	Video Length	Resolution	Reference Split	# Reference Videos	Model	Skip Frame #	Seed
UCF101	16, 128	128, 256	train+test	2048, full	I3D, VideoMAE-v2-SSv2	1	0
Sky	16, 128	128, 256	train	2048, full	I3D, VideoMAE-v2-SSv2	1	0
Taichi	16, 128	128, 256	train	2048, full	I3D, VideoMAE-v2-SSv2	1	0
Kinetics	16	128, 256	train	2048, full	I3D, VideoMAE-v2-SSv2	1	0
Kinetics	128	128, 256	train	2048	I3D, VideoMAE-v2-SSv2	1	0
FFS	16, 128	128, 256	train	2048, full	I3D, VideoMAE-v2-SSv2	1	0

Citation

@inproceedings{ge2024content,
      title={On the Content Bias in Fréchet Video Distance},
      author={Ge, Songwei and Mahapatra, Aniruddha and Parmar, Gaurav and Zhu, Jun-Yan and Huang, Jia-Bin},
      booktitle = {Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR)},
      year={2024}
}

Acknowledgement

We thank Angjoo Kanazawa, Aleksander Holynski, Devi Parikh, and Yogesh Balaji for their early feedback and discussion. We thank Or Patashnik, Richard Zhang, and Hadi Alzayer for their helpful comments and paper proofreading. We thank Ivan Skorokhodov for his help with reproducing the StyleGAN-v ablation experiments. Part of the evaluation code is built on StyleGAN-v.

Licenses

All material in this repository is made available under the MIT License.

metric_utils.py is adapted from the stylegan-v metric_utils.py, which was built on top of StyleGAN2-ADA and restricted by the NVidia Source Code license .

VideoMAE-v2 checkpoint is publicly available. Please consider filling this questionaire to help improve the future works.