🤖 AI Summary
This work addresses a key limitation of diffusion models in dataset distillation: their tendency to optimize generative likelihood, which concentrates synthetic samples in high-density regions of the data distribution while neglecting boundary samples critical for classification. To mitigate this, the authors propose two complementary strategies—Inversion Matching (IM) fine-tuning and Selective Subgroup Sampling (S³). IM aligns the feature distributions of real and synthetic data through inversion-guided refinement, while S³ dynamically selects informative subgroups during training to enhance diversity and inter-class separability without requiring additional training. Together, these techniques significantly improve the discriminative utility and generalization capability of distilled data without compromising generation quality, achieving state-of-the-art performance among diffusion-based distillation methods across multiple benchmarks.
📝 Abstract
Dataset Distillation aims to synthesize compact datasets that can approximate the training efficacy of large-scale real datasets, offering an efficient solution to the increasing computational demands of modern deep learning. Recently, diffusion-based dataset distillation methods have shown great promise by leveraging the strong generative capacity of diffusion models to produce diverse and structurally consistent samples. However, a fundamental goal misalignment persists: diffusion models are optimized for generative likelihood rather than discriminative utility, resulting in over-concentration in high-density regions and inadequate coverage of boundary samples crucial for classification. To address this issue, we propose two complementary strategies. Inversion-Matching (IM) introduces an inversion-guided fine-tuning process that aligns denoising trajectories with their inversion counterparts, broadening distributional coverage and enhancing diversity. Selective Subgroup Sampling(S^3) is a training-free sampling mechanism that improves inter-class separability by selecting synthetic subsets that are both representative and distinctive. Extensive experiments demonstrate that our approach significantly enhances the discriminative quality and generalization of distilled datasets, achieving state-of-the-art performance among diffusion-based methods.