ICCV 2025 Papers

Few-shot font generation (FFG) aims to create new font images by imitating the style from a limited set of reference images, while maintaining the content from the source images. Although this task has achieved significant progress, most existing methods still suffer from the incorrect generation of complicated character structure and detailed font style. To address the above issues, in this paper, we regard font generation as a font transfer process from the source font to the target font, and construct a video generation framework to model this process. Moreover, a test-time condition alignment mechanism is further developed to enhance the consistency between the generated samples and the provided condition samples. Specifically, we first construct a diffusion-based image-to-image font generation framework for the few-shot font generation task. This framework is expanded into an image-to-video font generation framework by integrating temporal components and frame-index information, enabling the production of high-quality font videos that transition from the source font to the target font. Based on this framework, we develop a noise inversion mechanism in the generative process to perform content and style alignment between the generated samples and the provided condition samples, enhancing style consistency and structural accuracy. The experimental results show that our model achieves superior performance on FFG tasks, demonstrating the effectiveness of our method. We will release our code after publication.

Visual text rendering are widespread in various real-world applications, requiring careful font selection and typographic choices. Recent progress in diffusion transformer (DiT)-based text-to-image (T2I) models show promise in automating these processes. However, these methods still encounter challenges like inconsistent fonts, style variation, and limited fine-grained control, particularly at the word-level. This paper proposes a two-stage DiT-based pipeline to address these problems by enhancing controllability over typography and style in text rendering. We introduce typography control fine-tuning (TC-FT), an parameter-efficient fine-tuning method (on 5% key parameters) with enclosing typography control tokens (ETC-tokens), which enables precise word-level application of typographic features. To further address style inconsistency in text rendering, we propose a text-agnostic style control adapter (SCA) that prevents content leakage while enhancing style consistency. To implement TC-FT and SCA effectively, we incorporated HTML-render into the data synthesis pipeline and proposed the first word-level controllable dataset. Through comprehensive experiments, we demonstrate the effectiveness of our approach in achieving superior word-level typographic control, font consistency, and style consistency in text rendering tasks. Our project page is available at this site.

Pixel Processor Arrays (PPAs) are vision sensors that embed data and processing into every pixel element. PPAs can execute visual processing directly at the point of light capture, and output only sparse, high-level information. This is in sharp contrast with the conventional visual pipeline, where whole images must be transferred from sensor to processor. This sparse data readout also provides several major benefits such as higher frame rate, lower energy consumption and lower bandwidth requirements. In this work, we demonstrate generation, matching and storage of binary descriptors for visual keypoint features, entirely upon PPA with no need to output images to external processing, making our approach inherently privacy-aware.Our method spreads descriptors across multiple pixel-processors, which allows for significantly larger descriptors than any prior pixel-processing works. These large descriptors can be used for a range of tasks such as place and object recognition. We demonstrate the accuracy of our in-pixel feature matching up to ~94.5%, at ~210fps, across a range of datasets, with a greater than 100xreduction in data transfer and bandwidth requirements over traditional cameras.

Bridging different modalities lies at the heart of cross-modality generation. While conventional approaches treat the text modality as a conditioning signal that gradually guides the denoising process from Gaussian noise to the target image modality, we explore a much simpler paradigm--directly evolving between text and image modalities through flow matching. This requires projecting both modalities into a shared latent space, which poses a significant challenge due to their inherently different representations: text is highly semantic and encoded as 1D tokens, whereas images are spatially redundant and represented as 2D latent embeddings. To address this, we introduce FlowTok, a minimal framework that seamlessly flows across text and images by encoding images into a compact 1D token representation. Compared to prior methods, this design reduces the latent space size by 3.3x at an image resolution of 256, eliminating the need for complex conditioning mechanisms or noise scheduling. Moreover, FlowTok naturally extends to image-to-text generation under the same formulation. With its streamlined architecture centered around compact 1D tokens, FlowTok is highly memory-efficient, requires significantly fewer training resources, and achieves much faster sampling speeds--all while delivering performance comparable to state-of-the-art models. Code is available at https://github.com/TACJu/FlowTok.

Contemporary video stylization approaches struggle to achieve artistic stylization while preserving temporal consistency. While generator-based methods produce visually striking stylized results, they suffer from flickering artifacts in dynamic motion scenarios and require prohibitive computational resources. Conversely, non-generative techniques frequently show either temporal inconsistency or inadequate style preservation.We address these limitations by adapting the physics-inspired transport principles from the Transport-based Neural Style Transfer (TNST) framework (originally developed for volumetric fluid stylization) to enforce inter-frame consistency in video stylization.Our framework employs two complementary transformation fields for artistic stylization: a geometric stylization velocity field governing deformation and an orthogonality-regularized color transfer field managing color adaptations. We further strengthen temporal consistency through two key enhancements to our field architecture: a momentum-preserving strategy mitigating vibration artifacts, and an occlusion-aware temporal lookup strategy addressing motion trailing artifacts. Extensive experiments demonstrate FlowStyler's superior performance across dual dimensions: Compared to generator-based approaches, we achieve 4xlower short-term warping errors, while maintaining comparable style fidelity; Against non-generative methods, FlowStyler attains 22% higher style fidelity with slightly improved temporal stability.

We present FlowSeek, a novel framework for optical flow requiring minimal hardware resources for training. FlowSeek marries the latest advances on the design space of optical flow networks with cutting-edge single-image depth foundation models and classical low-dimensional motion parametrization, implementing a compact, yet accurate architecture. FlowSeek is trained on a single consumer-grade GPU, a hardware budget about 8x lower compared to most recent methods, and still achieves superior cross-dataset generalization on Sintel Final and KITTI, with a relative improvement of 10 and 15% over the previous state-of-the-art SEA-RAFT, as well as on Spring and LayeredFlow datasets.

3D Gaussian splatting enables high-quality novel view synthesis (NVS) at real-time frame rates. However, its quality drops sharply as we depart from the training views. Thus, dense captures are needed to match the high-quality expectations of applications like Virtual Reality (VR). However, such dense captures are very laborious and expensive to obtain. Existing works have explored using 2D generative models to alleviate this requirement by distillation or generating additional training views. These models typically rely on a noise-to-data generative process conditioned only on a handful of reference input views, leading to hallucinations, inconsistent generation results, and subsequent reconstruction artifacts. Instead, we propose a multi-view, flow matching model that learns a flow to directly connect novel view renderings from possibly sparse reconstructions to renderings that we expect from dense reconstructions. This enables augmenting scene captures with consistent, generated views to improve reconstruction quality. Our model is trained on a novel dataset of 3.6M image pairs and can process up to 45 views at 540x960 resolution (91K tokens) on one H100 GPU in a single forward pass. Our pipeline consistently improves NVS in sparse- and dense-view scenarios, leading to higher-quality reconstructions than prior works across multiple, widely-used NVS benchmarks.

Editing real images using a pre-trained text-to-image (T2I) diffusion/flow model often involves inverting the image into its corresponding noise map. However, inversion by itself is typically insufficient for obtaining satisfactory results, and therefore many methods additionally intervene in the sampling process. Such methods achieve improved results but are not seamlessly transferable between model architectures. Here, we introduce FlowEdit, a text-based editing method for pre-trained T2I flow models, which is inversion-free, optimization-free and model agnostic. Our method constructs an ODE that directly maps between the source and target distributions (corresponding to the source and target text prompts) and achieves a lower transport cost than the inversion approach. This leads to state-of-the-art results, as we illustrate with Stable Diffusion 3 and FLUX.

Flow matching is a recent state-of-the-art framework for generative modeling based on ordinary differential equations (ODEs). While closely related to diffusion models, it provides a more general perspective on generative modeling.Although inverse problem solving has been extensively explored using diffusion models, it has not been rigorously examined within the broader context of flow models. Therefore, here we extend the diffusion inverse solvers (DIS)-- which perform posterior sampling by combining a denoising diffusion prior with an likelihood gradient--into the flow framework. Specifically, by driving the flow-version of Tweedie's formula, we decompose the flow ODE into two components: one for clean image estimation and the other for noise estimation.By integrating the likelihood gradient and stochastic noise into each component, respectively, we demonstrate that posterior sampling for inverse problem solving can be effectively achieved using flows. Our proposed solver, Flow-Driven Posterior Sampling (FlowDPS), can also be seamlessly integrated into a latent flow model with a transformer architecture. Across four linear inverse problems, we confirm that FlowDPS outperforms state-of-the-art alternatives, all without requiring additional training.

Despite recent advances in Rectified Flow Models (RFMs), unlocking their full potential for controlled generation tasks--such as inverse problems and image editing--remains a significant hurdle. Although RFMs and Diffusion Models (DMs) represent state-of-the-art approaches in generative modeling, their reliance on computationally demanding backpropagation through ODE solvers and inversion strategies often undermines efficiency and precision. In this paper, we present FlowChef, a novel training, inversion, and gradient-free inference-time steering strategy for RFMs that deterministically guides the denoising process. We first develop a theoretical and empirical understanding of the vector-field dynamics of RFMs in efficiently guiding the denoising trajectory. Specifically, leveraging the straightness and smooth Jacobian properties, we derive the mathematical relationship between gradients of rectified flow ODEs. We extend our theoretical findings to solve linear-inverse problems, image editing, classifier guidance, and many more tasks. We perform extensive evaluations and show that FlowChef significantly exceeds baselines in terms of performance, memory, and time requirements, achieving new state-of-the-art results. Remarkably, for the first time, it scales effortlessly to billion-parameter models such as Flux. Project Page: https://flowchef.github.io/

Long-form video understanding has always been a challenging problem due to the significant redundancy in both temporal and spatial contents. This challenge is further exacerbated by the limited context length of Multimodal Large Language Models (MLLMs). To address this issue, many previous works have attempted to extract key video information, where the "key" is typically semantic-aware and heavily dependent on the CLIP model as prior. In this paper, we propose Flow4Agent, a novel framework that pioneeringly incorporates motion priors from optical flow to facilitate LLM-based long video understanding. Flow4Agent mitigates the redundancy in long videos at both temporal and spatial levels through two core modules: Temporal Granularity Optimization (TGO) adaptively refines frame-level hierarchies, which first leverages coarse flow priors to group similar visual contents and then applies semantic priors to filter out highly irrelevant scene information. Motion Token Pruning (MTP) further refines the intra-frame visual representations, pruning high-redundancy video tokens using fine-grained optical flow information. Extensive experiments demonstrate that our Flow4Agent outperforms existing methods across a wide range of video MLLM benchmarks, especially for hour-level video understanding tasks, achieving 64.7% on Video-MME, 71.4% on MLVU and 60.4% on LongVideoBench.

Whole Slide Image (WSI) classification has been widely used in pathological diagnosis and prognosis prediction, and it is commonly formulated as a weakly-supervised Multiple Instance Learning (MIL) problem because of the large size of WSIs and the difficulty of obtaining fine-grained annotations. In the MIL formulation, a WSI is treated as a bag and the patches cut from it are treated as its instances, and most existing methods first extract instance features and then aggregate them into bag feature using attention-based mechanism for bag-level prediction. These models are trained using only bag-level labels, so they often lack instance-level insights and lose detailed semantic information, which limits their bag-level classification performance and damages their ability to explore high-expressive information. In this paper, we propose Flow-MIL, which leverages normalizing flow-based Latent Semantic Embedding Space (LSES) to enhance feature representation. By mapping patches into the simple and highly-expressive latent space LSES, Flow-MIL achieves effective slide-level aggregation while preserving critical semantic information. We also introduce Gaussian Mixture Model-based Latent Semantic Prototypes (LSP) within the LSES to capture class-specific pathological distribution for each class and refine pseudo instance labels. Extensive experiments on three public WSI datasets show that Flow-MIL outperforms recent SOTA methods in both bag-level and instance-level classification and offers improved interpretability.

Since the advent of popular visual generation frameworks like VQGAN and Latent Diffusion Models, state-of-the-art image generation systems have generally been two-stage systems that first tokenize or compress visual data into a lower-dimensional latent space before learning a generative model. Tokenizer training typically follows a standard recipe in which images are compressed and reconstructed subject to a combination of MSE, perceptual, and adversarial losses. Diffusion autoencoders have been proposed in prior work as a way to learn end-to-end perceptually-oriented image compression, but have not yet shown state-of-the-art performance on the competitive task of ImageNet-1K reconstruction. In this work, we propose FlowMo, a transformer-based diffusion autoencoder. FlowMo achieves a new state-of-the-art for image tokenization at multiple bitrates. We achieve this without using convolutions, adversarial losses, spatially-aligned 2D latent codes, or distilling from other tokenizers. Our key insight is that FlowMo training should be broken into a mode-matching pre-training stage and a mode-seeking post-training stage. We conduct extensive analysis and ablations, and we additionally train generative models atop the FlowMo tokenizer and verify the performance. We will release our code and model checkpoints upon acceptance.

We propose the Flow Stochastic Segmentation Network (Flow-SSN), a generative model for probabilistic segmentation featuring discrete-time autoregressive and modern continuous-time flow parameterisations. We prove fundamental limitations of the low-rank parameterisation of previous methods and show that Flow-SSNs can estimate arbitrarily high-rank pixel-wise covariances without assuming the rank or storing the distributional parameters. Flow-SSNs are also more efficient to sample from than standard diffusion-based segmentation models, as most of the model capacity is allocated to learning the base distribution of the flow, which constitutes an expressive prior. We apply Flow-SSNs to challenging medical imaging benchmarks and achieve state-of-the-art results.

Few-Shot Class-Incremental Learning (FSCIL) is challenged by limited data and expanding class spaces, leading to overfitting and catastrophic forgetting. Existing methods, which often freeze feature extractors and use Nearest Class Mean classifiers, sacrifice adaptability to new feature distributions. To address these issues, we propose Flexi-FSCIL, a semi-supervised framework that integrates three novel strategies: Adaptive Gated Residual Fusion (AGRF), Attention-Guided Dynamic Hybrid Distillation (ADHD), and Prototype Offset Equilibrium (POE). Flexi-FSCIL effectively balances stability and plasticity in FSCIL. AGRF resolves the rigidity of frozen feature extractors by integrating both frozen and trainable components, enabling adaptive feature learning while retaining old-class knowledge. ADHD tackles the imbalance between old and new tasks by dynamically aligning features using cross-attention maps and direct matching, preserving old-class knowledge while facilitating new-class learning. POE addresses the issue of prototype drift in semi-supervised settings by selecting high-quality unlabeled samples, maintaining feature space separability and preventing overfitting. Evaluated on three benchmark datasets, Flexi-FSCIL achieves state-of-the-art performance, significantly outperforming existing FSCIL methods with only 12.97 performance drop on CUB200.

In this work, we introduce FlexGen, a flexible framework designed to generate controllable and consistent multi-view images, conditioned on a single-view image, or a text prompt, or both. FlexGen tackles the challenges of controllable multi-view synthesis through additional conditioning on 3D-aware text annotations. We utilize the strong reasoning capabilities of GPT-4V to generate 3D-aware text annotations. By analyzing four orthogonal views of an object arranged as tiled multi-view images, GPT-4V can produce text annotations that include 3D-aware information with spatial relationship. By integrating the control signal with proposed adaptive dual-control module, our model can generate multi-view images that correspond to the specified text. FlexGen supports multiple controllable capabilities, allowing users to modify text prompts to generate reasonable and corresponding unseen parts. Additionally, users can influence attributes such as appearance and material properties, including metallic and roughness. Extensive experiments demonstrate that our approach offers enhanced multiple controllability, marking a significant advancement over existing multi-view diffusion models. This work has substantial implications for fields requiring rapid and flexible 3D content creation, including game development, animation, and virtual reality.

A versatile video depth estimation model should be consistent and accurate across frames, produce high-resolution depth maps, and support real-time streaming. We propose a method, FlashDepth, that satisfies all three requirements, performing depth estimation for a 2044x1148 streaming video at 24 FPS. We show that, with careful modifications to pretrained single-image depth models, these capabilities are enabled with relatively little data and training. We validate our approach across multiple unseen datasets against state-of-the-art depth models, and find that our method outperforms them in terms of boundary sharpness and speed by a significant margin, while maintaining competitive accuracy. We hope our model will enable various applications that require high-resolution depth, such as visual effects editing, and online decision-making, such as robotics. We release all code and model weights at https://github.com/Eyeline-Research/FlashDepth.

Benefiting from the advances in large language models and cross-modal alignment, existing multimodal large language models have achieved prominent performance in image and short video understanding. However, the understanding of long videos is still challenging, as their long-context nature results in significant computational and memory overhead. Most existing work treats long videos in the same way as short videos, which is inefficient for real-world applications and hard to generalize to even longer videos. To address these issues, we propose Flash-VStream, an efficient video language model capable of processing extremely long videos and responding to user queries in real time. Particularly, we design a Flash Memory module, containing a low-capacity context memory to aggregate long-context temporal information and model the distribution of information density, and a high-capacity augmentation memory to retrieve detailed spatial information based on this distribution. Compared to existing models, Flash-VStream achieves significant reductions in inference latency. Extensive experiments on long video benchmarks and comprehensive video benchmarks, i.e., EgoSchema, MLVU, LVBench, MVBench and Video-MME, demonstrate the state-of-the-art performance and outstanding efficiency of our method. Code is available at https://github.com/IVGSZ/Flash-VStream.

Talking head generation is gaining significant importance across various domains, with a growing demand for high-quality rendering. However, existing methods often suffer from identity leakage (IL) and rendering artifacts (RA), particularly in extreme cases. Through an in-depth analysis of previous approaches, we identify two key insights: (1) IL arises from identity information embedded within motion features, and (2) this identity information can be leveraged to address RA. Building on these findings, this paper introduces FixTalk, a novel framework designed to simultaneously resolve both issues for high-quality talking head generation. Firstly, we propose an Enhanced Motion Indicator (EMI) to effectively decouple identity information from motion features, mitigating the impact of IL on generated talking heads. To address RA, we introduce an Enhanced Detail Indicator (EDI), which utilizes the leaked identity information to supplement missing details, thus fixing the artifacts. Extensive experiments demonstrate that FixTalk effectively mitigates IL and RA, achieving superior performance compared to state-of-the-art methods.