Representation Loss Minimization with Randomized Selection Strategy for Efficient Environmental Fake Audio Detection
Orchid Chetia Phukan, Girish, Mohd Mujtaba Akhtar, Swarup Ranjan Behera, Nitin Choudhury, Arun Balaji Buduru, Rajesh Sharma, S. R Mahadeva Prasanna
TL;DR
This work tackles the challenge of high-dimensional representations in environmental audio deepfake detection by showing that randomly selecting 40–50% of foundation-model representations can preserve or even improve performance while drastically reducing downstream parameters and inference time. The approach outperforms traditional dimensionality reduction methods (PCA, SVD, KPCA, GRP) across both audio and multimodal foundation models, with LanguageBind often yielding the best detection metrics. The findings imply a practical, transferable strategy for efficient EADD deployment and invite further theoretical investigation into representation redundancy. Overall, the paper demonstrates a simple yet powerful method to achieve near-SOTA accuracy with substantially lower computational cost.
Abstract
The adaptation of foundation models has significantly advanced environmental audio deepfake detection (EADD), a rapidly growing area of research. These models are typically fine-tuned or utilized in their frozen states for downstream tasks. However, the dimensionality of their representations can substantially lead to a high parameter count of downstream models, leading to higher computational demands. So, a general way is to compress these representations by leveraging state-of-the-art (SOTA) unsupervised dimensionality reduction techniques (PCA, SVD, KPCA, GRP) for efficient EADD. However, with the application of such techniques, we observe a drop in performance. So in this paper, we show that representation vectors contain redundant information, and randomly selecting 40-50% of representation values and building downstream models on it preserves or sometimes even improves performance. We show that such random selection preserves more performance than the SOTA dimensionality reduction techniques while reducing model parameters and inference time by almost over half.
