Defense against adversarial attacks on spoofing countermeasures of ASV

Authors: Haibin Wu, Songxiang Liu, Helen Meng, Hung-yi Lee

Published: 2020-03-06 08:08:54+00:00

AI Summary

This paper proposes spatial smoothing (passive) and adversarial training (proactive) as defense methods to enhance the robustness of Automatic Speaker Verification (ASV) spoofing countermeasure models against adversarial attacks. Experimental results demonstrate that both methods effectively improve the models' resilience to adversarial examples.

Abstract

Various forefront countermeasure methods for automatic speaker verification (ASV) with considerable performance in anti-spoofing are proposed in the ASVspoof 2019 challenge. However, previous work has shown that countermeasure models are vulnerable to adversarial examples indistinguishable from natural data. A good countermeasure model should not only be robust against spoofing audio, including synthetic, converted, and replayed audios; but counteract deliberately generated examples by malicious adversaries. In this work, we introduce a passive defense method, spatial smoothing, and a proactive defense method, adversarial training, to mitigate the vulnerability of ASV spoofing countermeasure models against adversarial examples. This paper is among the first to use defense methods to improve the robustness of ASV spoofing countermeasure models under adversarial attacks. The experimental results show that these two defense methods positively help spoofing countermeasure models counter adversarial examples.


Key findings
Both spatial smoothing and adversarial training significantly improved the accuracy of the ASV spoofing countermeasure models when tested against adversarial examples. The combination of median or mean filtering with adversarial training yielded further accuracy improvements, while Gaussian filtering showed less benefit.
Approach
The authors employ two defense mechanisms: spatial smoothing, a passive technique that filters the input audio to reduce the impact of adversarial perturbations, and adversarial training, a proactive approach that trains the model on adversarially perturbed examples to improve robustness.
Datasets
LA partition of the ASVspoof 2019 dataset
Model(s)
VGG-like network and Squeeze-Excitation ResNet model (SENet)
Author countries
Taiwan, Hong Kong