Deepfake Detection that Generalizes Across Benchmarks
Deepfake Detection that Generalizes Across Benchmarks
Abstract
The generalization of deepfake detectors to unseen manipulation techniques remains a challenge for practical deployment. Although many approaches adapt foundation models by introducing significant architectural complexity, this work demonstrates that robust generalization is achievable through a parameter-efficient adaptation of one of the foundational pre-trained vision encoders. The proposed method, GenD, fine-tunes only the Layer Normalization parameters (zero point zero three percent of the total) and enhances generalization by enforcing a hyperspherical feature manifold using L two normalization and metric learning on it.
We conducted an extensive evaluation on fourteen benchmark datasets spanning from twenty nineteen to twenty twenty-five. The proposed method achieves state-of-the-art performance, outperforming more complex, recent approaches in average cross-dataset AU-ROC. Our analysis yields two primary findings for the field: one) training on paired real-fake data from the same source video is essential for mitigating shortcut learning and improving generalization, and two) detection difficulty on academic datasets has not strictly increased over time, with models trained on older, diverse datasets showing strong generalization capabilities.
This work delivers a computationally efficient and reproducible method, proving that state-of-the-art generalization is attainable by making targeted, minimal changes to a pre-trained foundational image encoder model. The code is at:
One. Introduction
One. Introduction
The proliferation of realistic facial deepfakes raises significant concerns regarding misinformation and malicious use, with AI-manipulated videos - those altered by techniques like face swapping or face reenactment - making detection challenging. Unlike fully synthetic content, such forgeries preserve the original context and leave subtle artifacts that are difficult for humans and machines to detect.
A primary issue affecting current detection methods is their limited ability to generalize. A model that has been trained to identify images altered by a particular deepfake generation algorithm often struggles when faced with examples produced by a new generation algorithm.
The generalization gap is the primary issue that we address in this work. Assuming the hypothesis that adapted large-scale, pre-trained foundational vision encoder can serve as a general foundation for deepfake detection, we build the proposed method in three variants, using Contrastive Language-Image Pre-training, Perception Encoder, and DINO models as feature extractors, which are known for their generalizable visual representations.
The proposed method consists of a vision encoder, whose outputs are L two-normalized. We then fine-tune only the parameters of the Layer Normalization blocks while keeping the rest frozen. Additionally, we propose using metric learning in this L two space to enhance generalization.
We benchmarked the generalization capabilities of the proposed model on fourteen deepfake video datasets released between twenty nineteen and twenty twenty-five, listed in Table one. To our knowledge, this represents the broadest evaluation in the deepfake literature. We show that the proposed model outperforms the most recent state-of-the-art methods on the majority of all available benchmarks.
In summary, our key contributions are as follows:
· A novel deepfake detection method called GenD. The method achieves the best average cross-dataset AUROC compared to recently released models.
· The most comprehensive evaluation in the deepfake literature covering datasets released throughout six years of research.
· A demonstration that to achieve the best generalization and prevent shortcut learning, it is essential to construct the training set consisting of real-fake pairs, where the fake video is generated from the real counterpart of the pair.