Oral Session
Oral Session 3A: Generative Diffusion Modeling
Breaking Semantic Boundaries: Distribution-Guided Semantic Exploration for Creative Generation
Fu Feng ⋅ Yucheng Xie ⋅ Ruixiao Shi ⋅ Xu Yang ⋅ Jing Wang ⋅ Xin Geng
Text-to-image (T2I) diffusion models effectively produce semantically aligned images, but their reliance on training distributions constrains their capacity for synthesizing truly novel, out-of-distribution concepts. Existing methods attempt to enhance creativity through semantic exploration, such as fusing known concept pairs, but the resulting images remain linguistically describable and confined to familiar semantic spaces. Inspired by the soft probabilistic outputs of classifiers on novel or out-of-distribution inputs, we propose Distribution-Conditional Generation, a paradigm that models novel concepts as image synthesis conditioned on class distributions, enabling controllable yet semantically unconstrained creative generation. Building on this, we propose DisTok, an encoder–decoder framework that unifies conditional and unconditional creative generation by decoding latent representations—either randomly sampled or mapped from conditions (e.g., class distributions)—into tokens representing novel concepts. DisTok is trained by iteratively sampling and fusing concept pairs from a dynamic pool to model progressively complex distributions, while enforcing semantic consistency through a vision-language model that aligns the class distributions of generated images with the input distributions. Extensive experiments demonstrate that DisTok enables efficient and flexible semantic exploration for token-level creative synthesis, achieving state-of-the-art text–image alignment and human preference.
Guiding a Diffusion Model by Swapping Its Tokens
Weijia Zhang ⋅ Yuehao Liu ⋅ Shanyan Guan ⋅ Wu Ran ⋅ Yanhao Ge ⋅ Wei Li ⋅ Chao Ma
Classifier-Free Guidance (CFG) is a widely used inference-time technique to boost the image quality of diffusion models. Yet, its reliance on text conditions prevents its use in unconditional generation. We propose a simple method to enable CFG-like guidance for both conditional and unconditional generation. The key idea is to generate a perturbed prediction via simple token swap operations, and use the direction between it and the clean prediction to steer sampling toward higher-fidelity distributions. In practice, we swap pairs of most semantically dissimilar tokens in either spatial or channel dimensions.Unlike existing methods that apply perturbation in a global or less constrained manner, our approach modifies only selected tokens, allowing finer control over perturbation and its influence on generated samples. Experiments on MS-COCO2014, MS-COCO 2017, and ImageNet datasets demonstrate that our Self-Swap Guidance (SSG), when applied to state-of-the-art diffusion models, outperforms previous condition-free methods in image fidelity and prompt alignment under different set-ups. Its fine-grained perturbation granularity also improves robustness, reducing side-effects across a wider range of perturbation strengths. Overall, SSG extends CFG to a broader scope of applications including both conditional and unconditional generation, and can be readily inserted into any diffusion model as a plug-in to gain immediate improvements.
PixelDiT: Pixel Diffusion Transformers for Image Generation
Yongsheng Yu ⋅ Wei Xiong ⋅ Weili Nie ⋅ Yichen Sheng ⋅ Shiqiu Liu ⋅ Jiebo Luo
Latent-space modeling has been the standard for Diffusion Transformers (DiTs). However, it relies on a two-stage pipeline where the pretrained autoencoder introduces lossy reconstruction, leading to error accumulation while hindering joint optimization. To address these issues, we propose PixelDiT, a single-stage, end-to-end model that eliminates the need for the autoencoder and learns the diffusion process directly in the pixel space. PixelDiT adopts a fully transformer-based architecture shaped by a dual-level design: a patch-level DiT that captures global semantics and a pixel-level DiT that refines texture details, enabling efficient training of a pixel-space diffusion model while preserving fine details. PixelDiT achieves 1.61 FID on ImageNet 256 and 2.21 FID on ImageNet 512, surpassing existing pixel generative models by a large margin. We further extend PixelDiT to text-to-image generation and pretrain it at the $1024^{2}$ resolution in pixel space. It achieves 0.74 on GenEval and 83.5 on DPG-bench, approaching the best latent diffusion models.
SeaCache: Spectral-Evolution-Aware Cache for Accelerating Diffusion Models
Jiwoo Chung ⋅ Sangeek Hyun ⋅ MinKyu Lee ⋅ Byeongju Han ⋅ Geonho Cha ⋅ Dongyoon Wee ⋅ Youngjun Hong ⋅ Jae-Pil Heo
Diffusion models are a strong backbone for visual generation, but their inherently sequential denoising process leads to slow inference. Previous methods accelerate sampling by caching and reusing intermediate outputs based on feature distances between adjacent timesteps. However, existing caching strategies typically rely on raw feature differences that entangle content and noise. This design overlooks spectral evolution, where low-frequency structure appears early and high-frequency detail is refined later. We introduce Spectral-Evolution-Aware Cache (SeaCache), a training-free cache schedule that bases reuse decisions on a spectrally aligned representation. Through theoretical and empirical analysis, we derive a Spectral-Evolution-Aware (SEA) filter that preserves content-relevant components while suppressing noise. Employing SEA-filtered input features to estimate redundancy leads to dynamic schedules that adapt to content while respecting the spectral priors of the underlying diffusion model. Extensive experiments on diverse visual generative models and the baselines show that SeaCache achieves state-of-the-art latency-quality trade-offs.
SenCache: Accelerating Diffusion Model Inference via Sensitivity-Aware Caching
Yasaman Haghighi ⋅ Alex Alahi
Diffusion models achieve state-of-the-art video generation but their many sequential denoising steps create a major computational bottleneck. Existing acceleration methods reuse cached model outputs at fixed timesteps chosen through heuristics, requiring heavy tuning and failing to adapt to each sample’s complexity. We address this with a principled, sensitivity-aware caching framework. We first formalize the caching problem by analyzing the network's output sensitivity with respect to changes in its inputs—namely, the noisy latent and the timestep. We demonstrate that this sensitivity is the key indicator of caching error. Building on this insight, we introduce Sensitivity-Aware Caching ($\text{SenCache}$), a dynamic strategy that adaptively selects which timesteps to cache on a per-sample basis. This allows for less caching on challenging samples and more aggressive acceleration on simpler ones. Our method provides a robust theoretical grounding for adaptive caching, offering an explanation for why previous empirical criteria are partially effective and extending them with a dynamic, sample-specific approach. Experiments on Wan 2.1, CogVideoX and LTX-Video models demonstrate that our method outperforms existing caching strategies in visual quality under similar computational budgets.
Streaming Diffusion Model for Fast Infrared and Visible Video Fusion
Jinyuan Liu ⋅ Ludan Sun ⋅ Tengyu Ma ⋅ Chunyan Yang ⋅ Zhiying Jiang ⋅ Long Ma ⋅ Risheng Liu ⋅ Xin Fan
Infrared and visible video fusion is pivotal for robust perceptual systems, aiming to synthesize a comprehensive video stream that leverages both thermal resilience and textured details. However, prevailing methods, by treating video as independent frames, inherently introduce temporal incoherence, such as flickering and ghosting artifacts. While diffusion models possess strong generative priors to remedy this, their iterative nature is prohibitively slow for video. To resolve this fundamental dilemma, we propose a streaming diffusion model for efficient infrared and visible video fusion, termed SDMFusion. Our key insight is to distill the generative prior of a pre-trained diffusion model into a one-step sampling framework, while explicitly modeling temporal dynamics. We design a memory-augmented latent pipeline where a temporal aggregation adapter aligns and propagates cross-frame features to ensure coherence, supported by a dedicated temporal consistency loss. This approach effectively decouples the challenge of achieving high fidelity from maintaining temporal stability. Extensive experiments on four benchmarks demonstrate that our method establishes a new state-of-the-art, generating fused videos with exceptional spatio-temporal consistency at a speed suitable for real-time application.