Diffusion-based contrastive learning for multimodal recommendation
摘要
Multimodal recommendation systems leverage rich auxiliary information to enhance performance. However, effectively fusing heterogeneous modalities while suppressing noise remains a significant challenge. To address this, we propose a diffusion-based contrastive learning framework for multimodal recommendation (DiffCLR). To overcome the structural bottlenecks of static graph propagation, DiffCLR introduces a multimodal graph denoising diffusion probabilistic model (MG-DDPM) for effective preference disentanglement. This component generates modality-specific interaction graphs by integrating a dynamic gating mechanism and a preference alignment constraint into the reverse denoising process. This generative paradigm allows the model to isolate intrinsic modality-dependent interests from noisy interactions. Additionally, we design a dual-path propagation architecture and a cross-view contrastive learning strategy to enhance the robustness and semantic alignment of the learned embeddings. Extensive experiments on four public benchmarks demonstrate that DiffCLR consistently outperforms state-of-the-art baselines, achieving an average improvement of 6.07%. The code for this work is available at https://github.com/sun2ot/DiffCLR.