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arXiv · 2507.22534

The Risks and Detection of Overestimated Privacy Protection in Voice Anonymisation

Abstract

Voice anonymisation aims to conceal the voice identity of speakers in speech recordings. Privacy protection is usually estimated from the difficulty of using a speaker verification system to re-identify the speaker post-anonymisation. Performance assessments are therefore dependent on the verification model as well as the anonymisation system. There is hence potential for privacy protection to be overestimated when the verification system is poorly trained, perhaps with mismatched data. In this paper, we demonstrate the insidious risk of overestimating anonymisation performance and show examples of exaggerated performance reported in the literature. For the worst case we identified, performance is overestimated by 74% relative. We then introduce a means to detect when performance assessment might be untrustworthy and show that it can identify all overestimation scenarios presented in the paper. Our solution is openly available as a fork of the 2024 VoicePrivacy Challenge evaluation toolkit.

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BibTeXRIS

Michele Panariello, Sarina Meyer, Pierre Champion, Xiaoxiao Miao, Massimiliano Todisco, Ngoc Thang Vu, Nicholas Evans. 2025-07-30. The Risks and Detection of Overestimated Privacy Protection in Voice Anonymisation. https://arxiv.org/abs/2507.22534

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