SPARK-IL: Spectral Retrieval-Augmented RAG for Knowledge-driven Deepfake Detection via Incremental Learning
This work addresses the limited generalization of existing AI-generated image detection methods to unseen generative models by proposing a novel incremental learning framework that integrates dual-path spectral analysis with retrieval-augmented generation (RAG). The approach employs four-band Fourier decomposition to extract frequency-domain features, combines a partially frozen ViT-L/14 encoder with Kolmogorov–Arnold Network (KAN)-based mixture-of-experts to model band-specific characteristics, and incorporates elastic weight consolidation for continual learning. Notably, it introduces, for the first time, a synergy between spectral consistency priors and RAG, leveraging a Milvus vector database for knowledge retrieval to enhance discriminative robustness. Evaluated on the UniversalFakeDetect benchmark encompassing 19 generative models, the method achieves an average accuracy of 94.6%, substantially outperforming current state-of-the-art techniques.