QAMO: Quality-aware Multi-centroid One-class Learning For Speech Deepfake Detection
Duc-Tuan Truong 1, Tianchi Liu 2, Ruijie Tao 2, Junjie Li 3, Kong Aik Lee 3, Eng Siong Chng 1
Published on arXiv
2509.20679
Output Integrity Attack
OWASP ML Top 10 — ML09
Key Finding
QAMO achieves 5.09% EER on the In-the-Wild dataset, outperforming previous one-class and quality-aware speech deepfake detection baselines using two quality-level centroids.
QAMO
Novel technique introduced
Recent work shows that one-class learning can detect unseen deepfake attacks by modeling a compact distribution of bona fide speech around a single centroid. However, the single-centroid assumption can oversimplify the bona fide speech representation and overlook useful cues, such as speech quality, which reflects the naturalness of the speech. Speech quality can be easily obtained using existing speech quality assessment models that estimate it through Mean Opinion Score. In this paper, we propose QAMO: Quality-Aware Multi-Centroid One-Class Learning for speech deepfake detection. QAMO extends conventional one-class learning by introducing multiple quality-aware centroids. In QAMO, each centroid is optimized to represent a distinct speech quality subspaces, enabling better modeling of intra-class variability in bona fide speech. In addition, QAMO supports a multi-centroid ensemble scoring strategy, which improves decision thresholding and reduces the need for quality labels during inference. With two centroids to represent high- and low-quality speech, our proposed QAMO achieves an equal error rate of 5.09% in In-the-Wild dataset, outperforming previous one-class and quality-aware systems.
Key Contributions
- Quality-Aware Multi-Centroid One-Class Learning (QAMO) framework that extends single-centroid one-class learning by assigning each centroid to a distinct MOS-derived speech quality subspace
- Multi-centroid ensemble scoring strategy that aggregates distances across all quality-aware centroids, eliminating the need for quality labels at inference time
- Achieves 5.09% EER on the In-the-Wild dataset, outperforming prior single-centroid one-class and quality-aware speech deepfake detection systems
🛡️ Threat Analysis
Proposes a novel speech deepfake detection architecture (QAMO) for identifying AI-generated/synthetic speech — a direct instance of AI-generated content detection, which is explicitly covered under ML09 output integrity. The contribution is the detection methodology itself, not a domain application of an existing detector.