SDiT: Semantic Region-Adaptive for Diffusion Transformers

Diffusion Transformers (DiTs) achieve state-of-the-art performance in text-to-image synthesis but remain computationally expensive due to the iterative nature of denoising and the quadratic cost of global attention. In this work, we observe that denoising dynamics are spatially non-uniform-background regions converge rapidly while edges and textured areas evolve much more actively. Building on this insight, we propose SDiT, a Semantic Region-Adaptive Diffusion Transformer that allocates computation according to regional complexity. SDiT introduces a training-free framework combining (1) semantic-aware clustering via fast Quickshift-based segmentation, (2) complexity-driven regional scheduling to selectively update informative areas, and (3) boundary-aware refinement to maintain spatial coherence. Without any model retraining or architectural modification, SDiT achieves up to 3.0x acceleration while preserving nearly identical perceptual and semantic quality to full-attention inference.

Dataset Distillation via the Wasserstein Metric

Dataset distillation (DD) offers a compelling approach in computer vision, with the goal of condensing extensive datasets into smaller synthetic versions without sacrificing much of the model performance. In this paper, we continue to study the methods for DD, by addressing its conceptually core objective: how to capture the essential representation of extensive datasets in smaller, synthetic forms. We propose a novel approach utilizing the Wasserstein distance, a metric rooted in optimal transport theory, to enhance distribution matching in DD. Our method leverages the Wasserstein barycenter, offering a geometrically meaningful way to quantify distribution differences and effectively capture the centroid of a set of distributions. Our approach retains the computational benefits of distribution matching-based methods while achieving new state-of-the-art performance on several benchmarks. To provide useful prior for learning the images, we embed the synthetic data into the feature space of pretrained classification models to conduct distribution matching. Extensive testing on various high-resolution datasets confirms the effectiveness and adaptability of our method, indicating the promising yet unexplored capabilities of Wasserstein metrics in dataset distillation.