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Jiao Chen 0001, Jiayi He, Fangfang Chen, Zuohong Lv, Jianhua Tang

Catastrophic forgetting remains a central challenge in continual learning (CL) with pre-trained models. While existing approaches typically freeze the backbone and fine-tune a small number of parameters to mitigate forgetting, they still rely on iterative error backpropagation and gradient-based optimization, which can be computationally intensive and less suitable for resource-constrained environments.To address this, we propose FoRo, a forward-only, gradient-free continual learning method. FoRo consists of a lightweight prompt tuning strategy and a novel knowledge encoding mechanism, both designed without modifying the pre-trained model. Specifically, prompt embeddings are inserted at the input layer and optimized using the Covariance Matrix Adaptation Evolution Strategy (CMA-ES), which mitigates distribution shifts and extracts high-quality task representations. Subsequently, task-specific knowledge is encoded into a knowledge encoding matrix via nonlinear random projection and recursive least squares, enabling incremental updates to the classifier without revisiting prior data.Experiments show that FoRo significantly reduces average forgetting and improves accuracy. Thanks to forward-only learning, FoRo reduces memory usage and run time while maintaining high knowledge retention across long task sequences. These results suggest that FoRo could serve as a promising direction for exploring continual learning with pre-trained models, especially in real-world multimedia applications where both efficiency and effectiveness are critical.

Jing Ma, Haochen Sun, Zeyuan Zang, Fangxiang Feng, Caixia Yuan, Lei Ren, Huixing Jiang, Wei Chen, Xiaojie Wang 0006

Visual reasoning is a key capability that significantly impacts the performance of multimodal tasks, such as compositional visual question answering and visual grounding. These tasks often require complex, multi-step reasoning processes. In recent years, several training-free methods for Vision-Language Models (VLMs) have emerged, with visual programming methods being proposed to enhance the capability of VLMs in visual reasoning tasks. While these methods have made some progress, they still face two primary challenges due to the lack of verification and refinement mechanisms for each action's output during the reasoning process: error accumulation and feedback delay, as well as insufficient utilization of multimodal contextual information. To address these challenges, we propose VL-DynaRefine, a training-free approach consisting of three modules: a planner, a verifier, and a refiner. The planner generates programmatic actions to solve the problem and executes each action in sequence, which is inspected by a verifier that reassesses the actions via confidence scores and determines whether refinement is necessary based on the evaluation results. In the refiner module, we incorporate a context-aware local refinement mechanism and a global refinement mechanism based on visual and action trajectories to reduce the impact of reasoning errors on the outcome. We evaluate our approach on multiple visual reasoning datasets, and the experimental results show that our method outperforms existing visual programming methods in both reasoning accuracy and efficiency, further validating its effectiveness in visual reasoning tasks.

Zhenni Yu, Li Zhao 0005, Guobao Xiao, Xiaoqin Zhang 0002

This paper introduces a new Segment Anything Model (SAM) that leverages reverse parameter configuration and test-time training to enhance its performance on Camouflaged Object Detection (COD), named SAM-TTT. While most existing SAM-based COD models primarily focus on enhancing SAM by extracting favorable features and amplifying its advantageous parameters, a crucial gap is identified: insufficient attention to adverse parameters that impair SAM's semantic understanding in downstream tasks. To tackle this issue, the Reverse SAM Parameter Configuration Module is proposed to effectively mitigate the influence of adverse parameters in a train-free manner by configuring SAM's parameters. Building on this foundation, the T-Visioner Module is unveiled to strengthen advantageous parameters by integrating Test-Time Training layers, originally developed for language tasks, into vision tasks. Test-Time Training layers represent a new class of sequence modeling layers characterized by linear complexity and an expressive hidden state. By integrating two modules, SAM-TTT simultaneously suppresses adverse parameters while reinforcing advantageous ones, significantly improving SAM's semantic understanding in COD task. Our experimental results on various COD benchmarks demonstrate that the proposed approach achieves state-of-the-art performance, setting a new benchmark in the field. The code will be available at https://github.com/guobaoxiao/SAM-TTT.

Xiaoqin Wang, Xianxu Hou, Meidan Ding, Junliang Chen 0002, Kaijun Deng, Jinheng Xie, Linlin Shen

Face parsing aims to segment facial images into key components such as eyes, lips, and eyebrows. While existing methods rely on dense pixel-level annotations, such annotations are expensive and labor-intensive to obtain. To reduce annotation cost, we introduce Weakly Supervised Face Parsing (WSFP), a new task setting that performs dense facial component segmentation using only weak supervision, such as image-level labels and natural language descriptions. WSFP introduces unique challenges due to the high co-occurrence and visual similarity of facial components, which lead to ambiguous activations and degraded parsing performance. To address this, we propose DisFaceRep, a representation disentanglement framework designed to separate co-occurring facial components through both explicit and implicit mechanisms. Specifically, we introduce a co-occurring component disentanglement strategy to explicitly reduce dataset-level bias, and a text-guided component disentanglement loss to guide component separation using language supervision implicitly. Extensive experiments on CelebAMask-HQ, LaPa, and Helen demonstrate the difficulty of WSFP and the effectiveness of DisFaceRep, which significantly outperforms existing weakly supervised semantic segmentation methods. The code will be released at https://github.com/CVI-SZU/DisFaceRep.

Yizhi Hu, Zezhao Tian, Xingqun Qi, Chen Su, Bingkun Yang, Junhui Yin, Muyi Sun, Man Zhang 0005, Zhenan Sun

Referring Expression Comprehension (REC) aims to localize specified entities or regions from the source image according to the given natural language descriptions. While existing methods enable single-entity localization, they overlook modeling the complex inter-entity relationship in more practical multi-entity scenes, which limits their ability to produce accurate and reliable results. Moreover, the lack of high-quality multi-entity datasets incorporating fine-grained and paired image-text-relation annotations also limits addressing this challenge. To achieve this task, we first manually construct a relation-aware multi-entity REC dataset with fine-grained relation and text annotations, namely ReMeX. Additionally, we propose ReMeREC, a novel framework that effectively integrates textual and visual cues to localize multiple entities while capturing their inter-relationship. Specifically, to mitigate the semantic ambiguity arising from the absence of explicit entity boundaries in the source natural language description, we introduce a novel Text-adaptive Multi-entity Perceptron (TMP). TMP dynamically infers both the quantity and span of entities from corresponding fine-grained text cues, thus deriving representations that preserve the unique characteristics of each entity. Meanwhile, we design the Entity Inter-relationship Reasoner (EIR) to enhance semantic distinctiveness relationship modeling, leading to a more profound perception of the global scene. Furthermore, to better capture the fine-grained linguistic prompts for delineating multiple entity boundaries and inter-relationship, we leverage LLMs to generate a small-scale textual dataset, dubbed EntityText, which serves as an effective auxiliary resource and further improves the textual understanding. Extensive experiments conducted on four benchmark datasets demonstrate the superior performance of our framework. Remarkably, ReMeREC achieves outstanding results in multi-entity grounding and complex relationship prediction, outperforming other counterparts by a large margin.

Yili Li, Gang Xiong 0001, Gaopeng Gou, Xiangyan Qu, Jiamin Zhuang, Zhen Li 0011, Junzheng Shi

Text-to-video retrieval essentially aims to train models to align visual content with textual descriptions accurately. Due to the impressive general multimodal knowledge demonstrated by image-text pretrained models such as CLIP, existing work has primarily focused on extending CLIP knowledge for video-text tasks. However, videos typically contain richer information than images. In current video-text datasets, textual descriptions can only reflect a portion of the video content, leading to partial misalignment in video-text matching. Therefore, directly aligning text representations with video representations can result in incorrect supervision, ignoring the inequivalence of information. In this work, we propose T2VParser to extract multiview semantic representations from text and video, achieving adaptive semantic alignment rather than aligning the entire representation. To extract corresponding representations from different modalities, we introduce Adaptive Decomposition Tokens, which consist of a set of learnable tokens shared across modalities. The goal of T2VParser is to emphasize precise alignment between text and video while retaining the knowledge of pretrained models. Experimental results demonstrate that T2VParser achieves accurate partial alignment through effective cross-modal content decomposition. The code is available at https://github.com/Lilidamowang/T2VParser.

Dexuan Xu, Yanyuan Chen, Yu Huang 0004, Shihao E, Yiwei Lou, Yongzhi Cao, Hanpin Wang, Meikang Qiu

Medical Visual Question Answering (Medical VQA) plays an important role in medical informatics. However, the robustness of existing medical VQA models is severely challenged by adversarial attacks. Current methods (e.g. adversarial training and noise-based reasoning) heavily rely on additional data or complex procedures and often ignore model-level robustness. To address these issues, we propose Multimodal Variational Masked Autoencoder (MVMAE), a novel pre-training framework designed to enhance the robustness of the medical VQA task. MVMAE leverages masked modeling and variational inference to extract robust multimodal features. The framework introduces a low-cost multimodal bottleneck fusion module and employs reparameterization to sample robust latent representations, ensuring effective feature fusion and reconstruction. Extensive experiments on public medical VQA datasets demonstrate that MVMAE significantly improves resistance to various adversarial attacks and outperforms other medical multimodal pre-training methods.

Qiyan Zhao, Xiaofeng Zhang 0006, Yiheng Li, Yun Xing 0001, Xiaosong Yuan, Feilong Tang, Sinan Fan, Xuhang Chen 0002, Da-Han Wang, Xu-Yao Zhang

Hallucinations pose a significant challenge in Large Vision Language Models (LVLMs), with misalignment between multimodal features identified as a key contributing factor. This paper reveals the negative impact of the long-term decay in Rotary Position Encoding (RoPE), used for positional modeling in LVLMs, on multimodal alignment. Concretely, under long-term decay, instruction tokens exhibit uneven perception of image tokens located at different positions within the two-dimensional space: prioritizing image tokens from the bottom-right region since in the one-dimensional sequence, these tokens are positionally closer to the instruction tokens. This biased perception leads to insufficient image-instruction interaction and suboptimal multimodal alignment. We refer to this phenomenon as ''image alignment bias.'' To enhance instruction's perception of image tokens at different spatial locations, we propose MCA-LLaVA, based on Manhattan distance, which extends the long-term decay to a two-dimensional, multi-directional spatial decay. MCA-LLaVA integrates the one-dimensional sequence order and two-dimensional spatial position of image tokens for positional modeling, mitigating hallucinations by alleviating image alignment bias. Experimental results of MCA-LLaVA across various hallucination and general benchmarks demonstrate its effectiveness and generality. The code can be accessed in https://github.com/ErikZ719/MCA-LLaVA.

Zhiyuan Fan, Keyi Liang

Video-to-Image Affordance Grounding aims to localize object affordances in static images by learning from human demonstration videos. However, existing fully supervised methods rely on paired image-video inputs during both training and inference, which significantly limits their practicality in real-world scenarios. Conversely, weakly supervised approaches support video-free inference but often struggle to capture the most critical interaction features necessary for affordance learning. To overcome these limitations, we propose a novel two-stage framework, VCL. In the first stage, we adopt the standard fully supervised paradigm to train the model, enabling it to effectively extract meaningful interaction features from demonstration videos. In the second stage, these extracted features are conceptualized, and a conceptual module is introduced to map natural language instructions into the concept space. Our approach establishes a new paradigm for affordance learning from demonstrations, enabling the model to learn from video but perform precise text-conditioned inference. Experiments on two benchmark datasets show that our base model outperforms previous state-of-the-art methods, while our text-conditioned model achieves competitive performance without requiring paired video inputs during inference. Code will be released at https://github.com/Fanzy27/VCL.

Xiangyu Shan, Heng Song, Junwu Zhu

In audio-visual joint analysis, generalized zero-shot learning (GZSL) aims to recognize unseen categories by aligning semantic information across modalities. However, significant challenges arise from temporal and semantic discrepancies between audio and video modalities. Traditional methods typically depend on static semantic embeddings, thereby overlooking the dynamic nature of these modalities and often resulting in modality imbalance. We propose the Dual-Factor Compensatory Clustering Network (DFCNet), an end-to-end framework for dynamic fusion and optimized alignment of heterogeneous modal information to address these limitations. DFCNet employs a multi-branch architecture, integrating a parallel multi-layer perceptron (MLP) for semantic modeling and a Bidirectional Long Short-Term Memory (BiLSTM) network for capturing temporal consistency. The Compensatory Fusion Block (CFB) employs tensor decomposition to facilitate cross-modal coupling, where the low-rank representation decomposition aligns intra-modal feature distributions. Additionally, we introduce the Dual-Factor Clustering Multi-objective Optimization Framework (DCMOF), which ensures gradient equilibrium and adaptively adjusts modality contribution weights to strengthen robust cross-modal alignment. Designed as a pluggable module, DFCNet can be seamlessly integrated into existing base models. Experimental results demonstrate that our framework significantly improves the performance of the Audio-Visual Cross-Modal Alignment (AVCA) model across multiple GZSL datasets. Ablation studies further validate the critical role of CFB in cross-modal alignment and highlight the significance of DCMOF in optimizing modality coordination. The code is available at https://github.com/ATKEROM/DFCNet.

Dingwei Zhang, Dong Zhang, Jinhui Tang 0001

Recently, query-based methods have achieved remarkable performance in Referring Video Object Segmentation (RVOS) by using textual static object queries to drive cross-modal alignment. However, these static queries are easily misled by distractors with similar appearance or motion, resulting in query selection bias. To address this issue, we propose Triple Query Former (TQF), which factorizes the referring query into three specialized components: an appearance query for static attributes, an intra-frame interaction query for spatial relations, and an inter-frame motion query for temporal association. Instead of relying solely on textual embeddings, our queries are dynamically constructed by integrating both linguistic cues and visual guidance. Furthermore, we introduce two motion-aware aggregation modules that enhance object token representations: Intra-frame Interaction Aggregation incorporates position-aware interactions among objects within a single frame, while Inter-frame Motion Aggregation leverages trajectory-guided alignment across frames to ensure temporal coherence. Extensive experiments on multiple RVOS benchmarks demonstrate the advantages of TQF and the effectiveness of our structured query design and motion-aware aggregation modules. The code is available at https://github.com/DavidZhang-1025/TQF.

Yonghyeon Jo, Janghyun Kim, Jinsun Park

Multi-label classification has recently demonstrated promising performance through CLIP-based unsupervised learning. However, existing CLIP-based approaches primarily focus on object-centric features, which limits their ability to capture rich contextual dependencies between objects and their surrounding scenes. In addition, the vision transformer architecture of CLIP exhibits a bias toward the most prominent object, often failing to recognize small or less conspicuous objects precisely. To address these limitations, we propose Background-Aware CLIP-GCN (BAC-GCN), a novel framework that explicitly models class-background interactions and is designed to capture fine-grained visual patterns of small objects effectively. BAC-GCN is composed of three key components: (i) a Similarity Kernel that extracts patch-level local features for each category (i.e., class and background), (ii) a CLIP-GCN that captures relational dependencies between local-global and class-background features, and (iii) a Re-Training for Small Objects (ReSO) strategy that enhances the representation of small and hard-to-learn objects by learning their distinctive visual characteristics. Therefore, our method facilitates a deeper understanding of complex visual contexts, enabling the model to make decisions by leveraging diverse visual cues and their contextual relationships. Extensive experiments demonstrate that BAC-GCN achieves state-of-the-art performance on three benchmark multi-label datasets: VOC07, COCO, and NUS, validating the effectiveness of our approach. The project page is available at: https://github.com/yonghyeonjo46/BAC-GCN.

Hanning Chen, Yang Ni 0001, Wenjun Huang 0001, Hyunwoo Oh, Yezi Liu, Tamoghno Das, Mohsen Imani

Large Vision Language Models (LVLMs) have been widely adopted to guide vision foundation models in performing reasoning segmentation tasks, achieving impressive performance. However, the substantial computational overhead associated with LVLMs presents a new challenge. The primary source of this computational cost arises from processing hundreds of image tokens. Therefore, an effective strategy to mitigate such overhead is to reduce the number of image tokens-a process known as image token pruning. Previous studies on image token pruning for LVLMs have primarily focused on high-level visual understanding tasks, such as visual question answering and image captioning. In contrast, guiding vision foundation models to generate accurate visual masks based on textual queries demands precise semantic and spatial reasoning capabilities. Consequently, pruning methods must carefully control individual image tokens throughout the LVLM reasoning process. Our empirical analysis reveals that existing methods struggle to adequately balance reductions in computational overhead with the necessity to maintain high segmentation accuracy. In this work, we propose LVLM_CSP, a novel training-free visual token pruning method specifically designed for LVLM-based reasoning segmentation tasks. LVLM_CSP consists of three stages: clustering, scattering, and pruning. Initially, the LVLM performs coarse-grained visual reasoning using a subset of selected image tokens. Next, fine-grained reasoning is conducted, and finally, most visual tokens are pruned in the last stage. Extensive experiments demonstrate that LVLM_CSP achieves a 65% reduction in image token inference FLOPs with virtually no accuracy degradation, and a 70% reduction with only a minor 1% drop in accuracy on the 7B LVLM.

Ziming Zhao 0008, Zhaoxuan Li, Tingting Li 0004, Fan Zhang 0010

Deep Neural Networks (DNNs) have become increasingly prevalent in various applications, yet they remain vulnerable to adversarial attacks, particularly through the use of adversarial examples (AEs). This paper introduces the concept of stealthy AE, which is benign before transmission through Online Social Networks (OSNs) but becomes adversarial after processing. The inherent transformations applied by OSNs, such as image compression and format conversion, can activate the properties of adversarial examples that are originally hidden. We present a suite of stealthy AE generation frameworks. Subsequently, our scheme involves the quality factor calculation, leveraging the diffusion model with differential JPEG layers to simulate OSN transmission, and utilizing the Lagrange multiplier method for AE generation optimization. Extensive experiments demonstrate that our method consistently outperforms seven state-of-the-art adversarial example generation techniques across multiple OSNs and victim models. Moreover, resistance detection evaluation and extended experiments with different attack settings also demonstrated the scalability of our scheme.

Shanshan Li, Jiawei Hou, Da Huang, Yanwei Fu 0001, Xiangyang Xue 0001

Visual language navigation (VLN) poses challenges in guiding agents through unseen environments based on natural language instructions. Existing methods either rely on imitation learning, for which training across various complex scenarios remains challenging, or leverage large visual language models (LVLMs) for zero-shot object recognition and expert iterative reasoning for improved scene understanding. Although LVLMs enhance target detection generalization, current VLN methods lack robustness in terms of environmental generalization and struggle with multi-step, coarsely directed instructions. Addressing these challenges, we introduce Ali-UI, a novel vision-language navigation approach that enables agents to navigate from random starting points in unvisited scenes and handle complex multi-step instructions. Specifically, we incorporate continuously accumulating global grid maps and local semantic maps as scene memory by employing frontier-based exploration. Multi-step coarsely directed commands are broken down with the assistance of LLaVA and matched with the scene, considering temporal and spatial alignment. Panoramic data are saved in topological form and queried by instruction segments for sequential navigation. Extensive experiments carried out in simulated environments demonstrate that Ali-UI outperforms existing state-of-the-art methods in terms of flexible human instructions and scene generalization, with the success rate improved by 23.37% and the SPL increased by 19.27% in R2R dataset.

Changtao Miao, Qi Chu 0001, Tao Gong, Zhentao Tan, Zhenchao Jin, Wanyi Zhuang, Man Luo, Honggang Hu, Nenghai Yu

With the advancement of face manipulation technology, forgery images in multi-face scenarios are gradually becoming a more complex and realistic challenge. Despite this, detection and localization methods for such multi-face manipulations remain underdeveloped. Traditional manipulation localization methods either indirectly derive detection results from localization masks, resulting in limited detection performance, or employ a naive two-branch structure to simultaneously obtain detection and localization results, which cannot effectively benefit the localization capability due to limited interaction between the two tasks. This paper proposes a new framework, namely MoNFAP, specifically tailored for multi-face manipulation detection and localization. The MoNFAP primarily introduces two novel modules: the Forgery-aware Unified Predictor (FUP) Module and the Mixture-of-Noises Module (MNM). The proposed FUP integrates detection and localization tasks using a token learning strategy and multiple forgery-aware transformers, which facilitates the use of classification information to enhance localization capability. Furthermore, to mitigate the interference from general semantic object information, we propose the MNM that leverages multiple noise extractors based on the mixture of experts concept. This allows the MNM to learn semantic-agnostic forgery features from general RGB features, further boosting the performance of our proposed framework. Finally, we establish a comprehensive benchmark for multi-face detection and localization, and the proposed MoNFAP achieves significant performance. The code is available: https://github.com/miaoct/MoNFAP.

Sijing Li, Tianwei Lin 0001, Lingshuai Lin, Wenqiao Zhang, Jiang Liu, Xiaoda Yang, Juncheng Li 0006, Yucheng He, Xiaohui Song, Jun Xiao 0001 等

Medical Large Vision-Language Models (Med-LVLMs) demonstrate significant potential in healthcare, but their reliance on general medical data and coarse-grained global visual understanding limits them in intelligent ophthalmic diagnosis. Currently, intelligent ophthalmic diagnosis faces three major challenges: (i) Data. The lack of deeply annotated, high-quality, multi-modal ophthalmic visual instruction data; (ii) Benchmark. The absence of a comprehensive and systematic benchmark for evaluating diagnostic performance; (iii) Model. The difficulty of adapting holistic visual architectures to fine-grained, region-specific ophthalmic lesion identification. In this paper, we propose the Eyecare Kit, which systematically tackles the aforementioned three key challenges with the tailored dataset, benchmark and model: First, we construct a multi-agent data engine with real-life ophthalmology data to produce Eyecare-100K, a high-quality ophthalmic visual instruction dataset. Subsequently, we design Eyecare-Bench, a benchmark that comprehensively evaluates the overall performance of LVLMs on intelligent ophthalmic diagnosis tasks across multiple dimensions. Finally, we develop the EyecareGPT, optimized for fine-grained ophthalmic visual understanding thoroughly, which incorporates an adaptive resolution mechanism and a layer-wise dense connector. Extensive experimental results indicate that the EyecareGPT achieves state-of-the-art performance in a range of ophthalmic tasks, underscoring its significant potential for the advancement of open research in intelligent ophthalmic diagnosis. Our project is available at https://github.com/DCDmllm/EyecareGPT.

Yangxu Yin, Honglong Chen, Yudong Gao, Peng Sun 0003, Liantao Wu, Zhe Li 0026, Weifeng Liu 0001

Backdoor attacks pose a significant threat to deep neural networks, as backdoored models would misclassify poisoned samples with specific triggers into target classes while maintaining normal performance on clean samples. Among these, multi-target backdoor attacks can simultaneously target multiple classes. However, existing multi-target backdoor attacks all follow the dirty-label paradigm, where poisoned samples are mislabeled, and most of them require an extremely high poisoning rate. This makes them easily detectable by manual inspection. In contrast, clean-label attacks are more stealthy, as they avoid modifying the labels of poisoned samples. However, they generally struggle to achieve stable and satisfactory attack performance and often fail to scale effectively to multi-target attacks. To address this issue, we propose the Feature-based Full-target Clean-label Backdoor Attacks (FFCBA) which consists of two paradigms: Feature-Spanning Backdoor Attacks (FSBA) and Feature-Migrating Backdoor Attacks (FMBA). FSBA leverages class-conditional autoencoders to generate noise triggers that align perturbed in-class samples with the original category's features, ensuring the effectiveness, intra-class consistency, inter-class specificity and natural-feature correlation of triggers. While FSBA supports swift and efficient attacks, its cross-model attack capability is relatively weak. FMBA employs a two-stage class-conditional autoencoder training process that alternates between using out-of-class samples and in-class samples. This allows FMBA to generate triggers with strong target-class features, making it highly effective for cross-model attacks. We conduct experiments on multiple datasets and models, the results show that FFCBA achieves outstanding attack performance and maintains desirable robustness against the state-of-the-art backdoor defenses. Our source code is available at (https://github.com/YangxvYin/FFCBA_code).

Junkang Liu, Fanhua Shang, Yuxuan Tian, Hongying Liu 0001, Yuanyuan Liu 0001

In federated learning (FL), multi-step local updates and data heterogeneity usually lead to sharper global minima, which degrades the performance of the global model. Popular FL algorithms integrate sharpness-aware minimization (SAM) into local training to address this issue. However, in the high data heterogeneity setting, the flatness in local training does not imply the flatness of the global model. Therefore, minimizing the sharpness of the local loss surfaces on the client data does not enable the effectiveness of SAM in FL to improve the generalization ability of the global model. We define the flatness distance to explain this phenomenon. By rethinking the SAM in FL and theoretically analyzing the flatness distance, we propose a novel FedNSAM algorithm that accelerates the SAM algorithm by introducing global Nesterov momentum into the local update to harmonize the consistency of global and local flatness. FedNSAM uses the global Nesterov momentum as the direction of local estimation of client global perturbations and extrapolation. Theoretically, we prove a tighter convergence bound than FedSAM by Nesterov extrapolation. Empirically, we conduct comprehensive experiments on CNN and Transformer models to verify the superior performance and efficiency of FedNSAM. The code is available at https://github.com/junkangLiu0/FedNSAM.

Jingxing Guo, Guilian Chen, Yimu Sun, Huisi Wu, Jing Qin 0001

Automatic segmentation of echocardiography videos is crucial for computer-aided cardiovascular function assessment in clinical practice. However, it is a challenging task owing to the existence of massive speckle noise, the large shape variations of heart structures between frames, and limited annotations. In this paper, we propose a novel semi-supervised video segmentation model to comprehensively meet these challenges. The proposed approach has two key techniques. First, we propose a dual-stream architecture that processes spatial and temporal features through separate pathways to capture structural details and motion patterns, then enhances spatiotemporal representations by interacting these decomposed features with query features generated from the original input. Second, as speckle noise primarily concentrates in high-frequency regions, we extend the traditional dilated convolution from a frequency perspective, enabling it to adaptively adjust the dilation rate and convolution kernel weights based on high frequency speckle noise information. This enables the network to focus on specific frequency bands, thereby enhancing its ability to capture both low-frequency context and high-frequency local details. Extensive experiments on the CAMUS and EchoNet-Dynamic datasets demonstrate that our method outperforms existing state-of-the-art methods in terms of both accuracy and inference speed. Codes are available at https://github.com/guojx2255/HSCA-SDC.