pwc-archive/papers-with-abstracts huggingface dataset:
Focus3D: A Practical Method to Adaptively Focus ISAR Data and Provide 3-D Information for Automatic Target Recognition
Authors: John R. Bennett
Date: 2025-04-17 00:00:00

To improve ATR identification of ships at sea requires an advanced ISAR processor - one that not only provides focused images but can also determine the pose of the ship. This tells us whether the image shows a profile (vertical plane) view, a plan (horizontal plane) view or some view in between. If the processor can provide this information, then the ATR processor can try to match the images with known vertical or horizontal features of ships and, in conjunction with estimated ship length, narrow the set of possible identifications. This paper extends the work of Melendez and Bennett [M-B, Ref. 1] by combining a focus algorithm with a method that models the angles of the ship relative to the radar. In M-B the algorithm was limited to a single angle and the plane of rotation was not determined. This assumption may be fine for a short time image where there is limited data available to determine the pose. However, the present paper models the ship rotation with two angles - aspect angle, representing rotation in the horizontal plane, and tilt angle, representing variations in the effective grazing angle to the ship.
Weak Cube R-CNN: Weakly Supervised 3D Detection using only 2D Bounding Boxes
Authors: Andreas Lau Hansen, Lukas Wanzeck, Dim P. Papadopoulos
Date: 2025-04-17 00:00:00
Tasks: 3D Object Detection, Monocular 3D Object Detection, object-detection, Object Detection, Weakly Supervised 3D Detection

Monocular 3D object detection is an essential task in computer vision, and it has several applications in robotics and virtual reality. However, 3D object detectors are typically trained in a fully supervised way, relying extensively on 3D labeled data, which is labor-intensive and costly to annotate. This work focuses on weakly-supervised 3D detection to reduce data needs using a monocular method that leverages a singlecamera system over expensive LiDAR sensors or multi-camera setups. We propose a general model Weak Cube R-CNN, which can predict objects in 3D at inference time, requiring only 2D box annotations for training by exploiting the relationship between 2D projections of 3D cubes. Our proposed method utilizes pre-trained frozen foundation 2D models to estimate depth and orientation information on a training set. We use these estimated values as pseudo-ground truths during training. We design loss functions that avoid 3D labels by incorporating information from the external models into the loss. In this way, we aim to implicitly transfer knowledge from these large foundation 2D models without having access to 3D bounding box annotations. Experimental results on the SUN RGB-D dataset show increased performance in accuracy compared to an annotation time equalized Cube R-CNN baseline. While not precise for centimetre-level measurements, this method provides a strong foundation for further research.
Enabling Fast and Accurate Crowdsourced Annotation for Elevation-Aware Flood Extent Mapping
Authors: Landon Dyken, Saugat Adhikari, Pravin Poudel, Steve Petruzza, Da Yan, Will Usher, Sidharth Kumar
Date: 2024-07-31 00:00:00

Mapping the extent of flood events is a necessary and important aspect of disaster management. In recent years, deep learning methods have evolved as an effective tool to quickly label high resolution imagery and provide necessary flood extent mappings. These methods, though, require large amounts of annotated training data to create models that are accurate and robust to new flooded imagery. In this work, we present FloodTrace, a web-based application that enables effective crowdsourcing of flooded region annotation for machine learning applications. To create this application, we conducted extensive interviews with domain experts to produce a set of formal requirements. Our work brings topological segmentation tools to the web and greatly improves annotation efficiency compared to the state-of-the-art. The user-friendliness of our solution allows researchers to outsource annotations to non-experts and utilize them to produce training data with equal quality to fully expert-labeled data. We conducted a user study to confirm the effectiveness of our application in which 266 graduate students annotated high-resolution aerial imagery from Hurricane Matthew in North Carolina. Experimental results show the efficiency benefits of our application for untrained users, with median annotation time less than half the state-of-the-art annotation method. In addition, using our aggregation and correction framework, flood detection models trained on crowdsourced annotations were able to achieve performance equal to models trained on fully expert-labeled annotations, while requiring a fraction of the time on the part of the expert.
LIFT+: Lightweight Fine-Tuning for Long-Tail Learning
Authors: Jiang-Xin Shi, Tong Wei, Yu-Feng Li
Date: 2025-04-17 00:00:00
Tasks: Data Augmentation, Long-tail Learning

The fine-tuning paradigm has emerged as a prominent approach for addressing long-tail learning tasks in the era of foundation models. However, the impact of fine-tuning strategies on long-tail learning performance remains unexplored. In this work, we disclose that existing paradigms exhibit a profound misuse of fine-tuning methods, leaving significant room for improvement in both efficiency and accuracy. Specifically, we reveal that heavy fine-tuning (fine-tuning a large proportion of model parameters) can lead to non-negligible performance deterioration on tail classes, whereas lightweight fine-tuning demonstrates superior effectiveness. Through comprehensive theoretical and empirical validation, we identify this phenomenon as stemming from inconsistent class conditional distributions induced by heavy fine-tuning. Building on this insight, we propose LIFT+, an innovative lightweight fine-tuning framework to optimize consistent class conditions. Furthermore, LIFT+ incorporates semantic-aware initialization, minimalist data augmentation, and test-time ensembling to enhance adaptation and generalization of foundation models. Our framework provides an efficient and accurate pipeline that facilitates fast convergence and model compactness. Extensive experiments demonstrate that LIFT+ significantly reduces both training epochs (from $\sim$100 to $\leq$15) and learned parameters (less than 1%), while surpassing state-of-the-art approaches by a considerable margin. The source code is available at https://github.com/shijxcs/LIFT-plus.
ChartQA-X: Generating Explanations for Charts
Authors: Shamanthak Hegde, Pooyan Fazli, Hasti Seifi
Date: 2025-04-17 00:00:00
Tasks: Decision Making, Explanation Generation, Informativeness, Question Answering

The ability to interpret and explain complex information from visual data in charts is crucial for data-driven decision-making. In this work, we address the challenge of providing explanations alongside answering questions about chart images. We present ChartQA-X, a comprehensive dataset comprising various chart types with 28,299 contextually relevant questions, answers, and detailed explanations. These explanations are generated by prompting six different models and selecting the best responses based on metrics such as faithfulness, informativeness, coherence, and perplexity. Our experiments show that models fine-tuned on our dataset for explanation generation achieve superior performance across various metrics and demonstrate improved accuracy in question-answering tasks on new datasets. By integrating answers with explanatory narratives, our approach enhances the ability of intelligent agents to convey complex information effectively, improve user understanding, and foster trust in the generated responses.
Dynamic Memory-enhanced Transformer for Hyperspectral Image Classification
Authors: Muhammad Ahmad, Manuel Mazzara, Salvatore Distefano, Adil Mehmood Khan
Date: 2025-04-17 00:00:00
Tasks: Classification, Hyperspectral Image Classification, image-classification, Image Classification

Hyperspectral image (HSI) classification remains a challenging task due to the intricate spatial-spectral correlations. Existing transformer models excel in capturing long-range dependencies but often suffer from information redundancy and attention inefficiencies, limiting their ability to model fine-grained relationships crucial for HSI classification. To overcome these limitations, this work proposes MemFormer, a lightweight and memory-enhanced transformer. MemFormer introduces a memory-enhanced multi-head attention mechanism that iteratively refines a dynamic memory module, enhancing feature extraction while reducing redundancy across layers. Additionally, a dynamic memory enrichment strategy progressively captures complex spatial and spectral dependencies, leading to more expressive feature representations. To further improve structural consistency, we incorporate a spatial-spectral positional encoding (SSPE) tailored for HSI data, ensuring continuity without the computational burden of convolution-based approaches. Extensive experiments on benchmark datasets demonstrate that MemFormer achieves superior classification accuracy, outperforming state-of-the-art methods.
SSTAF: Spatial-Spectral-Temporal Attention Fusion Transformer for Motor Imagery Classification
Authors: Ummay Maria Muna, Md. Mehedi Hasan Shawon, Md Jobayer, Sumaiya Akter, Saifur Rahman Sabuj
Date: 2025-04-17 00:00:00
Tasks: EEG, Motor Imagery

Brain-computer interfaces (BCI) in electroencephalography (EEG)-based motor imagery classification offer promising solutions in neurorehabilitation and assistive technologies by enabling communication between the brain and external devices. However, the non-stationary nature of EEG signals and significant inter-subject variability cause substantial challenges for developing robust cross-subject classification models. This paper introduces a novel Spatial-Spectral-Temporal Attention Fusion (SSTAF) Transformer specifically designed for upper-limb motor imagery classification. Our architecture consists of a spectral transformer and a spatial transformer, followed by a transformer block and a classifier network. Each module is integrated with attention mechanisms that dynamically attend to the most discriminative patterns across multiple domains, such as spectral frequencies, spatial electrode locations, and temporal dynamics. The short-time Fourier transform is incorporated to extract features in the time-frequency domain to make it easier for the model to obtain a better feature distinction. We evaluated our SSTAF Transformer model on two publicly available datasets, the EEGMMIDB dataset, and BCI Competition IV-2a. SSTAF Transformer achieves an accuracy of 76.83% and 68.30% in the data sets, respectively, outperforms traditional CNN-based architectures and a few existing transformer-based approaches.
The Tenth NTIRE 2025 Image Denoising Challenge Report
Authors: Lei Sun, Hang Guo, Bin Ren, Luc van Gool, Radu Timofte, Yawei Li, Xiangyu Kong, Hyunhee Park, Xiaoxuan Yu, Suejin Han, Hakjae Jeon, Jia Li, Hyung-Ju Chun, Donghun Ryou, Inju Ha, Bohyung Han, JingYu Ma, Zhijuan Huang, Huiyuan Fu, Hongyuan Yu, Boqi Zhang, Jiawei Shi, Heng Zhang, Huadong Ma, Deepak Kumar Tyagi, Aman Kukretti, Gajender Sharma, Sriharsha Koundinya, Asim Manna, Jun Cheng, Shan Tan, Jun Liu, Jiangwei Hao, Jianping Luo, Jie Lu, Satya Narayan Tazi, Arnim Gautam, Aditi Pawar, Aishwarya Joshi, Akshay Dudhane, Praful Hambadre, Sachin Chaudhary, Santosh Kumar Vipparthi, Subrahmanyam Murala, Jiachen Tu, Nikhil Akalwadi, Vijayalaxmi Ashok Aralikatti, Dheeraj Damodar Hegde, G Gyaneshwar Rao, Jatin Kalal, Chaitra Desai, Ramesh Ashok Tabib, Uma Mudenagudi, Zhenyuan Lin, Yubo Dong, Weikun Li, Anqi Li, Ang Gao, Weijun Yuan, Zhan Li, Ruting Deng, Yihang Chen, Yifan Deng, Zhanglu Chen, Boyang Yao, Shuling Zheng, Feng Zhang, Zhiheng Fu, Anas M. Ali, Bilel Benjdira, Wadii Boulila, Jan Seny, Pei Zhou, Jianhua Hu, K. L. Eddie Law, Jaeho Lee, M. J. Aashik Rasool, Abdur Rehman, SMA Sharif, Seongwan Kim, Alexandru Brateanu, Raul Balmez, Ciprian Orhei, Cosmin Ancuti, Zeyu Xiao, Zhuoyuan Li, Ziqi Wang, Yanyan Wei, Fei Wang, Kun Li, Shengeng Tang, Yunkai Zhang, Weirun Zhou, Haoxuan Lu
Date: 2025-04-16 00:00:00
Tasks: Denoising, Image Denoising, valid

This paper presents an overview of the NTIRE 2025 Image Denoising Challenge ({\sigma} = 50), highlighting the proposed methodologies and corresponding results. The primary objective is to develop a network architecture capable of achieving high-quality denoising performance, quantitatively evaluated using PSNR, without constraints on computational complexity or model size. The task assumes independent additive white Gaussian noise (AWGN) with a fixed noise level of 50. A total of 290 participants registered for the challenge, with 20 teams successfully submitting valid results, providing insights into the current state-of-the-art in image denoising.
Hysteresis-Aware Neural Network Modeling and Whole-Body Reinforcement Learning Control of Soft Robots
Authors: Zongyuan Chen, Yan Xia, Jiayuan Liu, Jijia Liu, Wenhao Tang, Jiayu Chen, Feng Gao, Longfei Ma, Hongen Liao, Yu Wang, Chao Yu, Boyu Zhang, Fei Xing
Date: 2025-04-18 00:00:00

Soft robots exhibit inherent compliance and safety, which makes them particularly suitable for applications requiring direct physical interaction with humans, such as surgical procedures. However, their nonlinear and hysteretic behavior, resulting from the properties of soft materials, presents substantial challenges for accurate modeling and control. In this study, we present a soft robotic system designed for surgical applications and propose a hysteresis-aware whole-body neural network model that accurately captures and predicts the soft robot's whole-body motion, including its hysteretic behavior. Building upon the high-precision dynamic model, we construct a highly parallel simulation environment for soft robot control and apply an on-policy reinforcement learning algorithm to efficiently train whole-body motion control strategies. Based on the trained control policy, we developed a soft robotic system for surgical applications and validated it through phantom-based laser ablation experiments in a physical environment. The results demonstrate that the hysteresis-aware modeling reduces the Mean Squared Error (MSE) by 84.95 percent compared to traditional modeling methods. The deployed control algorithm achieved a trajectory tracking error ranging from 0.126 to 0.250 mm on the real soft robot, highlighting its precision in real-world conditions. The proposed method showed strong performance in phantom-based surgical experiments and demonstrates its potential for complex scenarios, including future real-world clinical applications.
A Model-Based Approach to Imitation Learning through Multi-Step Predictions
Authors: Haldun Balim, Yang Hu, Yuyang Zhang, Na Li
Date: 2025-04-18 00:00:00
Tasks: Decision Making, Imitation Learning, Model Predictive Control

Imitation learning is a widely used approach for training agents to replicate expert behavior in complex decision-making tasks. However, existing methods often struggle with compounding errors and limited generalization, due to the inherent challenge of error correction and the distribution shift between training and deployment. In this paper, we present a novel model-based imitation learning framework inspired by model predictive control, which addresses these limitations by integrating predictive modeling through multi-step state predictions. Our method outperforms traditional behavior cloning numerical benchmarks, demonstrating superior robustness to distribution shift and measurement noise both in available data and during execution. Furthermore, we provide theoretical guarantees on the sample complexity and error bounds of our method, offering insights into its convergence properties.
Integration of a Graph-Based Path Planner and Mixed-Integer MPC for Robot Navigation in Cluttered Environments
Authors: Joshua A. Robbins, Stephen J. Harnett, Andrew F. Thompson, Sean Brennan, Herschel C. Pangborn
Date: 2025-04-17 00:00:00
Tasks: Model Predictive Control, Robot Navigation

The ability to update a path plan is a required capability for autonomous mobile robots navigating through uncertain environments. This paper proposes a re-planning strategy using a multilayer planning and control framework for cases where the robot's environment is partially known. A medial axis graph-based planner defines a global path plan based on known obstacles where each edge in the graph corresponds to a unique corridor. A mixed-integer model predictive control (MPC) method detects if a terminal constraint derived from the global plan is infeasible, subject to a non-convex description of the local environment. Infeasibility detection is used to trigger efficient global re-planning via medial axis graph edge deletion. The proposed re-planning strategy is demonstrated experimentally.
Beyond Reconstruction: A Physics Based Neural Deferred Shader for Photo-realistic Rendering
Authors: Zhuo He, Paul Henderson, Nicolas Pugeault
Date: 2025-04-16 00:00:00
Tasks: Image Generation

Deep learning based rendering has demonstrated major improvements for photo-realistic image synthesis, applicable to various applications including visual effects in movies and photo-realistic scene building in video games. However, a significant limitation is the difficulty of decomposing the illumination and material parameters, which limits such methods to reconstruct an input scene, without any possibility to control these parameters. This paper introduces a novel physics based neural deferred shading pipeline to decompose the data-driven rendering process, learn a generalizable shading function to produce photo-realistic results for shading and relighting tasks, we also provide a shadow estimator to efficiently mimic shadowing effect. Our model achieves improved performance compared to classical models and a state-of-art neural shading model, and enables generalizable photo-realistic shading from arbitrary illumination input.
VGDFR: Diffusion-based Video Generation with Dynamic Latent Frame Rate
Authors: Zhihang Yuan, Rui Xie, Yuzhang Shang, Hanling Zhang, Siyuan Wang, Shengen Yan, Guohao Dai, Yu Wang
Date: 2025-04-16 00:00:00
Tasks: Video Generation

Diffusion Transformer(DiT)-based generation models have achieved remarkable success in video generation. However, their inherent computational demands pose significant efficiency challenges. In this paper, we exploit the inherent temporal non-uniformity of real-world videos and observe that videos exhibit dynamic information density, with high-motion segments demanding greater detail preservation than static scenes. Inspired by this temporal non-uniformity, we propose VGDFR, a training-free approach for Diffusion-based Video Generation with Dynamic Latent Frame Rate. VGDFR adaptively adjusts the number of elements in latent space based on the motion frequency of the latent space content, using fewer tokens for low-frequency segments while preserving detail in high-frequency segments. Specifically, our key contributions are: (1) A dynamic frame rate scheduler for DiT video generation that adaptively assigns frame rates for video segments. (2) A novel latent-space frame merging method to align latent representations with their denoised counterparts before merging those redundant in low-resolution space. (3) A preference analysis of Rotary Positional Embeddings (RoPE) across DiT layers, informing a tailored RoPE strategy optimized for semantic and local information capture. Experiments show that VGDFR can achieve a speedup up to 3x for video generation with minimal quality degradation.
Modeling L1 Influence on L2 Pronunciation: An MFCC-Based Framework for Explainable Machine Learning and Pedagogical Feedback
Authors: Peyman Jahanbin
Date: 2025-04-18 00:00:00

This study investigates the extent to which Mel-Frequency Cepstral Coefficients (MFCCs) capture first language (L1) transfer in extended second language (L2) English speech. Speech samples from Mandarin and American English L1 speakers were extracted from the GMU Speech Accent Archive, converted to WAV format, and processed to obtain thirteen MFCCs per speaker. A multi-method analytic framework combining inferential statistics (t-tests, MANOVA, Canonical Discriminant Analysis) and machine learning (Random Forest classification) identified MFCC-1 (broadband energy), MFCC-2 (first formant region), and MFCC-5 (voicing and fricative energy) as the most discriminative features for distinguishing L1 backgrounds. A reduced-feature model using these MFCCs significantly outperformed the full-feature model, as confirmed by McNemar's test and non-overlapping confidence intervals. The findings empirically support the Perceptual Assimilation Model for L2 (PAM-L2) and the Speech Learning Model (SLM), demonstrating that L1-conditioned variation in L2 speech is both perceptually grounded and acoustically quantifiable. Methodologically, the study contributes to applied linguistics and explainable AI by proposing a transparent, data-efficient pipeline for L2 pronunciation modeling. The results also offer pedagogical implications for ESL/EFL instruction by highlighting L1-specific features that can inform intelligibility-oriented instruction, curriculum design, and speech assessment tools.
Cobra: Efficient Line Art COlorization with BRoAder References
Authors: Junhao Zhuang, Lingen Li, Xuan Ju, Zhaoyang Zhang, Chun Yuan, Ying Shan
Date: 2025-04-16 00:00:00
Tasks: Colorization, Image Generation, Line Art Colorization

The comic production industry requires reference-based line art colorization with high accuracy, efficiency, contextual consistency, and flexible control. A comic page often involves diverse characters, objects, and backgrounds, which complicates the coloring process. Despite advancements in diffusion models for image generation, their application in line art colorization remains limited, facing challenges related to handling extensive reference images, time-consuming inference, and flexible control. We investigate the necessity of extensive contextual image guidance on the quality of line art colorization. To address these challenges, we introduce Cobra, an efficient and versatile method that supports color hints and utilizes over 200 reference images while maintaining low latency. Central to Cobra is a Causal Sparse DiT architecture, which leverages specially designed positional encodings, causal sparse attention, and Key-Value Cache to effectively manage long-context references and ensure color identity consistency. Results demonstrate that Cobra achieves accurate line art colorization through extensive contextual reference, significantly enhancing inference speed and interactivity, thereby meeting critical industrial demands. We release our codes and models on our project page: https://zhuang2002.github.io/Cobra/.