Towards Data Drift Monitoring for Speech Deepfake Detection in the context of MLOps

Authors: Xin Wang, Wanying Ge, Junichi Yamagishi

Published: 2025-09-12 09:26:56+00:00

AI Summary

This paper investigates data drift monitoring for speech deepfake detection within an MLOps framework. It explores using distribution distances to monitor drift from a reference dataset caused by new text-to-speech (TTS) attacks and demonstrates that fine-tuning the detector with similarly drifted data reduces drift and improves detection performance.

Abstract

When being delivered in applications or services on the cloud, static speech deepfake detectors that are not updated will become vulnerable to newly created speech deepfake attacks. From the perspective of machine learning operations (MLOps), this paper tries to answer whether we can monitor new and unseen speech deepfake data that drifts away from a seen reference data set. We further ask, if drift is detected, whether we can fine-tune the detector using similarly drifted data, reduce the drift, and improve the detection performance. On a toy dataset and the large-scale MLAAD dataset, we show that the drift caused by new text-to-speech (TTS) attacks can be monitored using distances between the distributions of the new data and reference data. Furthermore, we demonstrate that fine-tuning the detector using data generated by the new TTS deepfakes can reduce the drift and the detection error rates.


Key findings
Drift caused by newer TTS attacks is larger than that of older attacks. Fine-tuning the detector with data from similar attacks reduces drift and improves detection performance, especially when using a larger amount of fine-tuning data. The choice of distance metric for drift detection appears less critical than the model and data used.
Approach
The authors monitor data drift by measuring the distance between feature distributions of new data and a reference dataset using Wasserstein-1, Kullback-Leibler divergence, and Kolmogorov-Smirnov distance metrics. If drift is detected, they fine-tune the deepfake detector using data generated by the new TTS attacks to reduce the drift and improve detection accuracy.
Datasets
A toy dataset (LJSpeech-TTS) with synthetic utterances from 12 TTS systems and the MLAAD dataset (English subset, version 7.0) with data from 54 TTS systems. ASVspoof 2019 development set used as reference data.
Model(s)
AASIST (an end-to-end detector), W2V (SSL-based detector with a small wav2vec 2.0 module), and XSLR2b (SSL-based detector with a large XLS-R module).
Author countries
Japan