mtybilly/Instruct2DS huggingface dataset:
Task-Conditioned Adaptation of Visual Features in Multi-Task Policy Learning
Authors: Pierre Marza, Laetitia Matignon, Olivier Simonin, Christian Wolf
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Successfully addressing a wide variety of tasks is a core ability of autonomous agents requiring flexibly adapting the underlying decision-making strategies and as we argue in this work also adapting the perception modules. An analogical argument would be the human visual system which uses top-down signals to focus attention determined by the current task. Similarly we adapt pre-trained large vision models conditioned on specific downstream tasks in the context of multi-task policy learning. We introduce task-conditioned adapters that do not require finetuning any pre-trained weights combined with a single policy trained with behavior cloning and capable of addressing multiple tasks. We condition the visual adapters on task embeddings which can be selected at inference if the task is known or alternatively inferred from a set of example demonstrations. To this end we propose a new optimization-based estimator. We evaluate the method on a wide variety of tasks from the CortexBench benchmark and show that compared to existing work it can be addressed with a single policy. In particular we demonstrate that adapting visual features is a key design choice and that the method generalizes to unseen tasks given a few demonstrations.
L0-Sampler: An L0 Model Guided Volume Sampling for NeRF
Authors: Liangchen Li, Juyong Zhang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Since its proposal Neural Radiance Fields (NeRF) has achieved great success in related tasks mainly adopting the hierarchical volume sampling (HVS) strategy for volume rendering. However the HVS of NeRF approximates distributions using piecewise constant functions which provides a relatively rough estimation. Based on the observation that a well-trained weight function w(t) and the L_0 distance between points and the surface have very high similarity we propose L_0-Sampler by incorporating the L_0 model into w(t) to guide the sampling process. Specifically we propose using piecewise exponential functions rather than piecewise constant functions for interpolation which can not only approximate quasi-L_0 weight distributions along rays quite well but can be easily implemented with a few lines of code change without additional computational burden. Stable performance improvements can be achieved by applying L_0-Sampler to NeRF and related tasks like 3D reconstruction. Code is available at https://ustc3dv.github.io/L0-Sampler/.
Hybrid Proposal Refiner: Revisiting DETR Series from the Faster R-CNN Perspective
Authors: Jinjing Zhao, Fangyun Wei, Chang Xu
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: With the transformative impact of the Transformer DETR pioneered the application of the encoder-decoder architecture to object detection. A collection of follow-up research e.g. Deformable DETR aims to enhance DETR while adhering to the encoder-decoder design. In this work we revisit the DETR series through the lens of Faster R-CNN. We find that the DETR resonates with the underlying principles of Faster R-CNN's RPN-refiner design but benefits from end-to-end detection owing to the incorporation of Hungarian matching. We systematically adapt the Faster R-CNN towards the Deformable DETR by integrating or repurposing each component of Deformable DETR and note that Deformable DETR's improved performance over Faster R-CNN is attributed to the adoption of advanced modules such as a superior proposal refiner (e.g. deformable attention rather than RoI Align). When viewing the DETR through the RPN-refiner paradigm we delve into various proposal refinement techniques such as deformable attention cross attention and dynamic convolution. These proposal refiners cooperate well with each other; thus we synergistically combine them to establish a Hybrid Proposal Refiner (HPR). Our HPR is versatile and can be incorporated into various DETR detectors. For instance by integrating HPR to a strong DETR detector we achieve an AP of 54.9 on the COCO benchmark utilizing a ResNet-50 backbone and a 36-epoch training schedule. Code and models are available at https://github.com/ZhaoJingjing713/HPR.
Practical Measurements of Translucent Materials with Inter-Pixel Translucency Prior
Authors: Zhenyu Chen, Jie Guo, Shuichang Lai, Ruoyu Fu, Mengxun Kong, Chen Wang, Hongyu Sun, Zhebin Zhang, Chen Li, Yanwen Guo
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Material appearance is a key component of photorealism with a pronounced impact on human perception. Although there are many prior works targeting at measuring opaque materials using light-weight setups (e.g. consumer-level cameras) little attention is paid on acquiring the optical properties of translucent materials which are also quite common in nature. In this paper we present a practical method for acquiring scattering properties of translucent materials based solely on ordinary images captured with unknown lighting and camera parameters. The key to our method is an inter-pixel translucency prior which states that image pixels of a given homogeneous translucent material typically form curves (dubbed translucent curves) in the RGB space of which the shapes are determined by the parameters of the material. We leverage this prior in a specially-designed convolutional neural network comprising multiple encoders a translucency-aware feature fusion module and a cascaded decoder. We demonstrate through both visual comparisons and quantitative evaluations that high accuracy can be achieved on a wide range of real-world translucent materials.
TurboSL: Dense Accurate and Fast 3D by Neural Inverse Structured Light
Authors: Parsa Mirdehghan, Maxx Wu, Wenzheng Chen, David B. Lindell, Kiriakos N. Kutulakos
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: We show how to turn a noisy and fragile active triangulation technique--three-pattern structured light with a grayscale camera--into a fast and powerful tool for 3D capture: able to output sub-pixel accurate disparities at megapixel resolution along with reflectance normals and a no-reference estimate of its own pixelwise 3D error. To achieve this we formulate structured-light decoding as a neural inverse rendering problem. We show that despite having just three or four input images--all from the same viewpoint--this problem can be tractably solved by TurboSL an algorithm that combines (1) a precise image formation model (2) a signed distance field scene representation and (3) projection pattern sequences optimized for accuracy instead of precision. We use TurboSL to reconstruct a variety of complex scenes from images captured at up to 60 fps with a camera and a common projector. Our experiments highlight TurboSL's potential for dense and highly-accurate 3D acquisition from data captured in fractions of a second.
Text2QR: Harmonizing Aesthetic Customization and Scanning Robustness for Text-Guided QR Code Generation
Authors: Guangyang Wu, Xiaohong Liu, Jun Jia, Xuehao Cui, Guangtao Zhai
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In the digital era QR codes serve as a linchpin connecting virtual and physical realms. Their pervasive integration across various applications highlights the demand for aesthetically pleasing codes without compromised scannability. However prevailing methods grapple with the intrinsic challenge of balancing customization and scannability. Notably stable-diffusion models have ushered in an epoch of high-quality customizable content generation. This paper introduces Text2QR a pioneering approach leveraging these advancements to address a fundamental challenge: concurrently achieving user-defined aesthetics and scanning robustness. To ensure stable generation of aesthetic QR codes we introduce the QR Aesthetic Blueprint (QAB) module generating a blueprint image exerting control over the entire generation process. Subsequently the Scannability Enhancing Latent Refinement (SELR) process refines the output iteratively in the latent space enhancing scanning robustness. This approach harnesses the potent generation capabilities of stable-diffusion models navigating the trade-off between image aesthetics and QR code scannability. Our experiments demonstrate the seamless fusion of visual appeal with the practical utility of aesthetic QR codes markedly outperforming prior methods. Codes are available at https://github.com/mulns/Text2QR
GS-IR: 3D Gaussian Splatting for Inverse Rendering
Authors: Zhihao Liang, Qi Zhang, Ying Feng, Ying Shan, Kui Jia
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: We propose GS-IR a novel inverse rendering approach based on 3D Gaussian Splatting (GS) that leverages forward mapping volume rendering to achieve photorealistic novel view synthesis and relighting results. Unlike previous works that use implicit neural representations and volume rendering (e.g. NeRF) which suffer from low expressive power and high computational complexity we extend GS a top-performance representation for novel view synthesis to estimate scene geometry surface material and environment illumination from multi-view images captured under unknown lighting conditions. There are two main problems when introducing GS to inverse rendering: 1) GS does not support producing plausible normal natively; 2) forward mapping (e.g. rasterization and splatting) cannot trace the occlusion like backward mapping (e.g. ray tracing). To address these challenges our GS-IR proposes an efficient optimization scheme that incorporates a depth-derivation-based regularization for normal estimation and a baking-based occlusion to model indirect lighting. The flexible and expressive GS representation allows us to achieve fast and compact geometry reconstruction photorealistic novel view synthesis and effective physically-based rendering. We demonstrate the superiority of our method over baseline methods through qualitative and quantitative evaluations on various challenging scenes.
SynFog: A Photo-realistic Synthetic Fog Dataset based on End-to-end Imaging Simulation for Advancing Real-World Defogging in Autonomous Driving
Authors: Yiming Xie, Henglu Wei, Zhenyi Liu, Xiaoyu Wang, Xiangyang Ji
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: To advance research in learning-based defogging algorithms various synthetic fog datasets have been developed. However exsiting datasets created using the Atmospheric Scattering Model (ASM) or real-time rendering engines often struggle to produce photo-realistic foggy images that accurately mimic the actual imaging process. This limitation hinders the effective generalization of models from synthetic to real data. In this paper we introduce an end-to-end simulation pipeline designed to generate photo-realistic foggy images. This pipeline comprehensively considers the entire physically-based foggy scene imaging process closely aligning with real-world image capture methods. Based on this pipeline we present a new synthetic fog dataset named SynFog which features both sky light and active lighting conditions as well as three levels of fog density. Experimental results demonstrate that models trained on SynFog exhibit superior performance in visual perception and detection accuracy compared to others when applied to real-world foggy images.
Video Harmonization with Triplet Spatio-Temporal Variation Patterns
Authors: Zonghui Guo, Xinyu Han, Jie Zhang, Shiguang Shan, Haiyong Zheng
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Video harmonization is an important and challenging task that aims to obtain visually realistic composite videos by automatically adjusting the foreground's appearance to harmonize with the background. Inspired by the short-term and long-term gradual adjustment process of manual harmonization we present a Video Triplet Transformer framework to model three spatio-temporal variation patterns within videos i.e. short-term spatial as well as long-term global and dynamic for video-to-video tasks like video harmonization. Specifically for short-term harmonization we adjust foreground appearance to consist with background in spatial dimension based on the neighbor frames; for long-term harmonization we not only explore global appearance variations to enhance temporal consistency but also alleviate motion offset constraints to align similar contextual appearances dynamically. Extensive experiments and ablation studies demonstrate the effectiveness of our method achieving state-of-the-art performance in video harmonization video enhancement and video demoireing tasks. We also propose a temporal consistency metric to better evaluate the harmonized videos. Code is available at https://github.com/zhenglab/VideoTripletTransformer.
TRINS: Towards Multimodal Language Models that Can Read
Authors: Ruiyi Zhang, Yanzhe Zhang, Jian Chen, Yufan Zhou, Jiuxiang Gu, Changyou Chen, Tong Sun
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Large multimodal language models have shown remarkable proficiency in understanding and editing images. However a majority of these visually-tuned models struggle to comprehend the textual content embedded in images primarily due to the limitation of training data. In this work we introduce TRINS: a Text-Rich image1 INStruction dataset with the objective of enhancing the reading ability of the multimodal large language model. TRINS is built upon LAION 2 using hybrid data annotation strategies that include machine-assisted and human-assisted annotation process. It contains 39153 text-rich images captions and 102437 questions. Specifically we show that the number of words per annotation in TRINS is significantly longer than that of related datasets providing new challenges. Furthermore we introduce a simple and effective architecture called a Language-Vision Reading Assistant (LaRA) which is good at understanding textual content within images. LaRA outperforms existing state-of-the-art multimodal large language models on the TRINS dataset as well as other classical benchmarks. Lastly we conducted a comprehensive evaluation with TRINS on various text-rich image understanding and generation tasks demonstrating its effectiveness.
Self-Supervised Representation Learning from Arbitrary Scenarios
Authors: Zhaowen Li, Yousong Zhu, Zhiyang Chen, Zongxin Gao, Rui Zhao, Chaoyang Zhao, Ming Tang, Jinqiao Wang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Current self-supervised methods can primarily be categorized into contrastive learning and masked image modeling. Extensive studies have demonstrated that combining these two approaches can achieve state-of-the-art performance. However these methods essentially reinforce the global consistency of contrastive learning without taking into account the conflicts between these two approaches which hinders their generalizability to arbitrary scenarios. In this paper we theoretically prove that MAE serves as a patch-level contrastive learning where each patch within an image is considered as a distinct category. This presents a significant conflict with global-level contrastive learning which treats all patches in an image as an identical category. To address this conflict this work abandons the non-generalizable global-level constraints and proposes explicit patch-level contrastive learning as a solution. Specifically this work employs the encoder of MAE to generate dual-branch features which then perform patch-level learning through a decoder. In contrast to global-level data augmentation in contrastive learning our approach leverages patch-level feature augmentation to mitigate interference from global-level learning. Consequently our approach can learn heterogeneous representations from a single image while avoiding the conflicts encountered by previous methods. Massive experiments affirm the potential of our method for learning from arbitrary scenarios.
Improved Zero-Shot Classification by Adapting VLMs with Text Descriptions
Authors: Oindrila Saha, Grant Van Horn, Subhransu Maji
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: The zero-shot performance of existing vision-language models (VLMs) such as CLIP is limited by the availability of large-scale aligned image and text datasets in specific domains. In this work we leverage two complementary sources of information -- descriptions of categories generated by large language models (LLMs) and abundant fine-grained image classification datasets -- to improve the zero-shot classification performance of VLMs across fine-grained domains. On the technical side we develop methods to train VLMs with this "bag-level" image-text supervision. We find that simply using these attributes at test-time does not improve performance but our training strategy for example on the iNaturalist dataset leads to an average improvement of 4-5% in zero-shot classification accuracy for novel categories of birds and flowers. Similar improvements are observed in domains where a subset of the categories was used to fine-tune the model. By prompting LLMs in various ways we generate descriptions that capture visual appearance habitat and geographic regions and pair them with existing attributes such as the taxonomic structure of the categories. We systematically evaluate their ability to improve zero-shot categorization in natural domains. Our findings suggest that geographic priors can be just as effective and are complementary to visual appearance. Our method also outperforms prior work on prompt-based tuning of VLMs. We release the benchmark consisting of 14 datasets at https://github.com/cvl-umass/AdaptCLIPZS which will contribute to future research in zero-shot recognition.
Living Scenes: Multi-object Relocalization and Reconstruction in Changing 3D Environments
Authors: Liyuan Zhu, Shengyu Huang, Konrad Schindler, Iro Armeni
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Research into dynamic 3D scene understanding has primarily focused on short-term change tracking from dense observations while little attention has been paid to long-term changes with sparse observations. We address this gap with MoRE a novel approach for multi-object relocalization and reconstruction in evolving environments. We view these environments as Living Scenes and consider the problem of transforming scans taken at different points in time into a 3D reconstruction of the object instances whose accuracy and completeness increase over time. At the core of our method lies an SE(3) equivariant representation in a single encoder-decoder network trained on synthetic data. This representation enables us to seamlessly tackle instance matching registration and reconstruction. We also introduce a joint optimization algorithm that facilitates the accumulation of point clouds originating from the same instance across multiple scans taken at different points in time. We validate our method on synthetic and real-world data and demonstrate state-of-the-art performance in both end-to-end performance and individual subtasks.
CricaVPR: Cross-image Correlation-aware Representation Learning for Visual Place Recognition
Authors: Feng Lu, Xiangyuan Lan, Lijun Zhang, Dongmei Jiang, Yaowei Wang, Chun Yuan
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Over the past decade most methods in visual place recognition (VPR) have used neural networks to produce feature representations. These networks typically produce a global representation of a place image using only this image itself and neglect the cross-image variations (e.g. viewpoint and illumination) which limits their robustness in challenging scenes. In this paper we propose a robust global representation method with cross-image correlation awareness for VPR named CricaVPR. Our method uses the attention mechanism to correlate multiple images within a batch. These images can be taken in the same place with different conditions or viewpoints or even captured from different places. Therefore our method can utilize the cross-image variations as a cue to guide the representation learning which ensures more robust features are produced. To further facilitate the robustness we propose a multi-scale convolution-enhanced adaptation method to adapt pre-trained visual foundation models to the VPR task which introduces the multi-scale local information to further enhance the cross-image correlation-aware representation. Experimental results show that our method outperforms state-of-the-art methods by a large margin with significantly less training time. The code is released at https://github.com/Lu-Feng/CricaVPR.
ECLIPSE: A Resource-Efficient Text-to-Image Prior for Image Generations
Authors: Maitreya Patel, Changhoon Kim, Sheng Cheng, Chitta Baral, Yezhou Yang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Text-to-image (T2I) diffusion models notably the unCLIP models (e.g. DALL-E-2) achieve state-of-the-art (SOTA) performance on various compositional T2I benchmarks at the cost of significant computational resources. The unCLIP stack comprises T2I prior and diffusion image decoder. The T2I prior model alone adds a billion parameters compared to the Latent Diffusion Models which increases the computational and high-quality data requirements. We introduce ECLIPSE a novel contrastive learning method that is both parameter and data-efficient. ECLIPSE leverages pre-trained vision-language models (e.g. CLIP) to distill the knowledge into the prior model. We demonstrate that the ECLIPSE trained prior with only 3.3% of the parameters and trained on a mere 2.8% of the data surpasses the baseline T2I priors with an average of 71.6% preference score under resource-limited setting. It also attains performance on par with SOTA big models achieving an average of 63.36% preference score in terms of the ability to follow the text compositions. Extensive experiments on two unCLIP diffusion image decoders Karlo and Kandinsky affirm that ECLIPSE priors consistently deliver high performance while significantly reducing resource dependency. Project page: https://eclipse-t2i.vercel.app/
Adaptive Bidirectional Displacement for Semi-Supervised Medical Image Segmentation
Authors: Hanyang Chi, Jian Pang, Bingfeng Zhang, Weifeng Liu
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Consistency learning is a central strategy to tackle unlabeled data in semi-supervised medical image segmentation (SSMIS) which enforces the model to produce consistent predictions under the perturbation. However most current approaches solely focus on utilizing a specific single perturbation which can only cope with limited cases while employing multiple perturbations simultaneously is hard to guarantee the quality of consistency learning. In this paper we propose an Adaptive Bidirectional Displacement (ABD) approach to solve the above challenge. Specifically we first design a bidirectional patch displacement based on reliable prediction confidence for unlabeled data to generate new samples which can effectively suppress uncontrollable regions and still retain the influence of input perturbations. Meanwhile to enforce the model to learn the potentially uncontrollable content a bidirectional displacement operation with inverse confidence is proposed for the labeled images which generates samples with more unreliable information to facilitate model learning. Extensive experiments show that ABD achieves new state-of-the-art performances for SSMIS significantly improving different baselines. Source code is available at https://github.com/chy-upc/ABD.
Accurate Training Data for Occupancy Map Prediction in Automated Driving Using Evidence Theory
Authors: Jonas Kälble, Sascha Wirges, Maxim Tatarchenko, Eddy Ilg
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Automated driving fundamentally requires knowledge about the surrounding geometry of the scene. Modern approaches use only captured images to predict occupancy maps that represent the geometry. Training these approaches requires accurate data that may be acquired with the help of LiDAR scanners. We show that the techniques used for current benchmarks and training datasets to convert LiDAR scans into occupancy grid maps yield very low quality and subsequently present a novel approach using evidence theory that yields more accurate reconstructions. We demonstrate that these are superior by a large margin both qualitatively and quantitatively and that we additionally obtain meaningful uncertainty estimates. When converting the occupancy maps back to depth estimates and comparing them with the raw LiDAR measurements our method yields a MAE improvement of 30% to 52% on nuScenes and 53% on Waymo over other occupancy ground-truth data. Finally we use the improved occupancy maps to train a state-of-the-art occupancy prediction method and demonstrate that it improves the MAE by 25% on nuScenes.
DiffusionLight: Light Probes for Free by Painting a Chrome Ball
Authors: Pakkapon Phongthawee, Worameth Chinchuthakun, Nontaphat Sinsunthithet, Varun Jampani, Amit Raj, Pramook Khungurn, Supasorn Suwajanakorn
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: We present a simple yet effective technique to estimate lighting in a single input image. Current techniques rely heavily on HDR panorama datasets to train neural networks to regress an input with limited field-of-view to a full environment map. However these approaches often struggle with real-world uncontrolled settings due to the limited diversity and size of their datasets. To address this problem we leverage diffusion models trained on billions of standard images to render a chrome ball into the input image. Despite its simplicity this task remains challenging: the diffusion models often insert incorrect or inconsistent objects and cannot readily generate chrome balls in HDR format. Our research uncovers a surprising relationship between the appearance of chrome balls and the initial diffusion noise map which we utilize to consistently generate high-quality chrome balls. We further fine-tune an LDR diffusion model (Stable Diffusion XL) with LoRA enabling it to perform exposure bracketing for HDR light estimation. Our method produces convincing light estimates across diverse settings and demonstrates superior generalization to in-the-wild scenarios.
Instance-level Expert Knowledge and Aggregate Discriminative Attention for Radiology Report Generation
Authors: Shenshen Bu, Taiji Li, Yuedong Yang, Zhiming Dai
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Automatic radiology report generation can provide substantial advantages to clinical physicians by effectively reducing their workload and improving efficiency. Despite the promising potential of current methods challenges persist in effectively extracting and preventing degradation of prominent features as well as enhancing attention on pivotal regions. In this paper we propose an Instance-level Expert Knowledge and Aggregate Discriminative Attention framework (EKAGen) for radiology report generation. We convert expert reports into an embedding space and generate comprehensive representations for each disease which serve as Preliminary Knowledge Support (PKS). To prevent feature disruption we select the representations in the embedding space with the smallest distances to PKS as Rectified Knowledge Support (RKS). Then EKAGen diagnoses the diseases and retrieves knowledge from RKS creating Instance-level Expert Knowledge (IEK) for each query image boosting generation. Additionally we introduce Aggregate Discriminative Attention Map (ADM) which uses weak supervision to create maps of discriminative regions that highlight pivotal regions. For training we propose a Global Information Self-Distillation (GID) strategy using an iteratively optimized model to distill global knowledge into EKAGen. Extensive experiments and analyses on IU X-Ray and MIMIC-CXR datasets demonstrate that EKAGen outperforms previous state-of-the-art methods.
Task-Adaptive Saliency Guidance for Exemplar-free Class Incremental Learning
Authors: Xialei Liu, Jiang-Tian Zhai, Andrew D. Bagdanov, Ke Li, Ming-Ming Cheng
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Exemplar-free Class Incremental Learning (EFCIL) aims to sequentially learn tasks with access only to data from the current one. EFCIL is of interest because it mitigates concerns about privacy and long-term storage of data while at the same time alleviating the problem of catastrophic forgetting in incremental learning. In this work we introduce task-adaptive saliency for EFCIL and propose a new framework which we call Task-Adaptive Saliency Supervision (TASS) for mitigating the negative effects of saliency drift between different tasks. We first apply boundary-guided saliency to maintain task adaptivity and plasticity on model attention. Besides we introduce task-agnostic low-level signals as auxiliary supervision to increase the stability of model attention. Finally we introduce a module for injecting and recovering saliency noise to increase the robustness of saliency preservation. Our experiments demonstrate that our method can better preserve saliency maps across tasks and achieve state-of-the-art results on the CIFAR-100 Tiny-ImageNet and ImageNet-Subset EFCIL benchmarks. Code is available at https://github.com/scok30/tass.
Rethinking the Spatial Inconsistency in Classifier-Free Diffusion Guidance
Authors: Dazhong Shen, Guanglu Song, Zeyue Xue, Fu-Yun Wang, Yu Liu
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Classifier-Free Guidance (CFG) has been widely used in text-to-image diffusion models where the CFG scale is introduced to control the strength of text guidance on the whole image space. However we argue that a global CFG scale results in spatial inconsistency on varying semantic strengths and suboptimal image quality. To address this problem we present a novel approach Semantic-aware Classifier-Free Guidance (S-CFG) to customize the guidance degrees for different semantic units in text-to-image diffusion models. Specifically we first design a training-free semantic segmentation method to partition the latent image into relatively independent semantic regions at each denoising step. In particular the cross-attention map in the denoising U-net backbone is renormalized for assigning each patch to the corresponding token while the self-attention map is used to complete the semantic regions. Then to balance the amplification of diverse semantic units we adaptively adjust the CFG scales across different semantic regions to rescale the text guidance degrees into a uniform level. Finally extensive experiments demonstrate the superiority of S-CFG over the original CFG strategy on various text-to-image diffusion models without requiring any extra training cost. our codes are available at https://github.com/SmilesDZgk/S-CFG.
Language-driven All-in-one Adverse Weather Removal
Authors: Hao Yang, Liyuan Pan, Yan Yang, Wei Liang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: All-in-one (AiO) frameworks restore various adverse weather degradations with a single set of networks jointly. To handle various weather conditions an AiO framework is expected to adaptively learn weather-specific knowledge for different degradations and shared knowledge for common patterns. However existing method: 1) rely on extra supervision signals which are usually unknown in real-world applications; 2) employ fixed network structures which restrict the diversity of weather-specific knowledge. In this paper we propose a Language-driven Restoration framework (LDR) to alleviate the aforementioned issues. First we leverage the power of pre-trained vision-language (PVL) models to enrich the diversity of weather-specific knowledge by reasoning about the occurrence type and severity of degradation generating description-based degradation priors. Then with the guidance of degradation prior we sparsely select restoration experts from a candidate list dynamically based on a Mixture-of-Experts (MoE) structure. This enables us to adaptively learn the weather-specific and shared knowledge to handle various weather conditions (e.g. unknown or mixed weather). Experiments on extensive restoration scenarios show our superior performance (see Fig. 1). The source code will be made available.
Each Test Image Deserves A Specific Prompt: Continual Test-Time Adaptation for 2D Medical Image Segmentation
Authors: Ziyang Chen, Yongsheng Pan, Yiwen Ye, Mengkang Lu, Yong Xia
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Distribution shift widely exists in medical images acquired from different medical centres and poses a significant obstacle to deploying the pre-trained semantic segmentation model in real-world applications. Test-time adaptation has proven its effectiveness in tackling the cross-domain distribution shift during inference. However most existing methods achieve adaptation by updating the pre-trained models rendering them susceptible to error accumulation and catastrophic forgetting when encountering a series of distribution shifts (i.e. under the continual test-time adaptation setup). To overcome these challenges caused by updating the models in this paper we freeze the pre-trained model and propose the Visual Prompt-based Test-Time Adaptation (VPTTA) method to train a specific prompt for each test image to align the statistics in the batch normalization layers. Specifically we present the low-frequency prompt which is lightweight with only a few parameters and can be effectively trained in a single iteration. To enhance prompt initialization we equip VPTTA with a memory bank to benefit the current prompt from previous ones. Additionally we design a warm-up mechanism which mixes source and target statistics to construct warm-up statistics thereby facilitating the training process. Extensive experiments demonstrate the superiority of our VPTTA over other state-of-the-art methods on two medical image segmentation benchmark tasks. The code and weights of pre-trained source models are available at https://github.com/Chen-Ziyang/VPTTA.
KTPFormer: Kinematics and Trajectory Prior Knowledge-Enhanced Transformer for 3D Human Pose Estimation
Authors: Jihua Peng, Yanghong Zhou, P. Y. Mok
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: This paper presents a novel Kinematics and Trajectory Prior Knowledge-Enhanced Transformer (KTPFormer) which overcomes the weakness in existing transformer-based methods for 3D human pose estimation that the derivation of Q K V vectors in their self-attention mechanisms are all based on simple linear mapping. We propose two prior attention modules namely Kinematics Prior Attention (KPA) and Trajectory Prior Attention (TPA) to take advantage of the known anatomical structure of the human body and motion trajectory information to facilitate effective learning of global dependencies and features in the multi-head self-attention. KPA models kinematic relationships in the human body by constructing a topology of kinematics while TPA builds a trajectory topology to learn the information of joint motion trajectory across frames. Yielding Q K V vectors with prior knowledge the two modules enable KTPFormer to model both spatial and temporal correlations simultaneously. Extensive experiments on three benchmarks (Human3.6M MPI-INF-3DHP and HumanEva) show that KTPFormer achieves superior performance in comparison to state-of-the-art methods. More importantly our KPA and TPA modules have lightweight plug-and-play designs and can be integrated into various transformer-based networks (i.e. diffusion-based) to improve the performance with only a very small increase in the computational overhead. The code is available at: https://github.com/JihuaPeng/KTPFormer.
MAPLM: A Real-World Large-Scale Vision-Language Benchmark for Map and Traffic Scene Understanding
Authors: Xu Cao, Tong Zhou, Yunsheng Ma, Wenqian Ye, Can Cui, Kun Tang, Zhipeng Cao, Kaizhao Liang, Ziran Wang, James M. Rehg, Chao Zheng
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Vision-language generative AI has demonstrated remarkable promise for empowering cross-modal scene understanding of autonomous driving and high-definition (HD) map systems. However current benchmark datasets lack multi-modal point cloud image and language data pairs. Recent approaches utilize visual instruction learning and cross-modal prompt engineering to expand vision-language models into this domain. In this paper we propose a new vision-language benchmark that can be used to finetune traffic and HD map domain-specific foundation models. Specifically we annotate and leverage large-scale broad-coverage traffic and map data extracted from huge HD map annotations and use CLIP and LLaMA-2 / Vicuna to finetune a baseline model with instruction-following data. Our experimental results across various algorithms reveal that while visual instruction-tuning large language models (LLMs) can effectively learn meaningful representations from MAPLM-QA there remains significant room for further advancements. To facilitate applying LLMs and multi-modal data into self-driving research we will release our visual-language QA data and the baseline models at GitHub.com/LLVM-AD/MAPLM.
EgoExoLearn: A Dataset for Bridging Asynchronous Ego- and Exo-centric View of Procedural Activities in Real World
Authors: Yifei Huang, Guo Chen, Jilan Xu, Mingfang Zhang, Lijin Yang, Baoqi Pei, Hongjie Zhang, Lu Dong, Yali Wang, Limin Wang, Yu Qiao
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Being able to map the activities of others into one's own point of view is one fundamental human skill even from a very early age. Taking a step toward understanding this human ability we introduce EgoExoLearn a large-scale dataset that emulates the human demonstration following process in which individuals record egocentric videos as they execute tasks guided by demonstration videos. Focusing on the potential applications of daily assistance and professional support EgoExoLearn contains egocentric and demonstration video data spanning 120 hours captured in daily life scenarios and specialized laboratories. Along with the videos we record high-quality gaze data and provide detailed multimodal annotations formulating a playground for modeling the human ability to bridge asynchronous procedural actions from different viewpoints. To this end we present benchmarks such as cross-view association cross-view action planning and cross-view referenced skill assessment along with detailed analysis. We expect EgoExoLearn can serve as an important resource for bridging the actions across views thus paving the way for creating AI agents capable of seamlessly learning by observing humans in the real world. The dataset and benchmark codes are available at https://github.com/OpenGVLab/EgoExoLearn.
Differentiable Micro-Mesh Construction
Authors: Yishun Dou, Zhong Zheng, Qiaoqiao Jin, Rui Shi, Yuhan Li, Bingbing Ni
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Micro-mesh (u-mesh) is a new graphics primitive for compact representation of extreme geometry consisting of a low-polygon base mesh enriched by per micro-vertex displacement. A new generation of GPUs supports this structure with hardware evolution on u-mesh ray tracing achieving real-time rendering in pixel level geometric details. In this article we present a differentiable framework to convert standard meshes into this efficient format offering a holistic scheme in contrast to the previous stage-based methods. In our construction context a u-mesh is defined where each base triangle is a parametric primitive which is then reparameterized with Laplacian operators for efficient geometry optimization. Our framework offers numerous advantages for high-quality u-mesh production: (i) end-to-end geometry optimization and displacement baking; (ii) enabling the differentiation of renderings with respect to umesh for faithful reprojectability; (iii) high scalability for integrating useful features for u-mesh production and rendering such as minimizing shell volume maintaining the isotropy of the base mesh and visual-guided adaptive level of detail. Extensive experiments on u-mesh construction for a large set of high-resolution meshes demonstrate the superior quality achieved by the proposed scheme.
Improved Implicit Neural Representation with Fourier Reparameterized Training
Authors: Kexuan Shi, Xingyu Zhou, Shuhang Gu
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Implicit Neural Representation (INR) as a mighty representation paradigm has achieved success in various computer vision tasks recently. Due to the low-frequency bias issue of vanilla multi-layer perceptron (MLP) existing methods have investigated advanced techniques such as positional encoding and periodic activation function to improve the accuracy of INR. In this paper we connect the network training bias with the reparameterization technique and theoretically prove that weight reparameterization could provide us a chance to alleviate the spectral bias of MLP. Based on our theoretical analysis we propose a Fourier reparameterization method which learns coefficient matrix of fixed Fourier bases to compose the weights of MLP. We evaluate the proposed Fourier reparameterization method on different INR tasks with various MLP architectures including vanilla MLP MLP with positional encoding and MLP with advanced activation function etc. The superiority approximation results on different MLP architectures clearly validate the advantage of our proposed method. Armed with our Fourier reparameterization method better INR with more textures and less artifacts can be learned from the training data. The codes are available at https://github.com/LabShuHangGU/FR-INR.
SNED: Superposition Network Architecture Search for Efficient Video Diffusion Model
Authors: Zhengang Li, Yan Kang, Yuchen Liu, Difan Liu, Tobias Hinz, Feng Liu, Yanzhi Wang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: While AI-generated content has garnered significant attention achieving photo-realistic video synthesis remains a formidable challenge. Despite the promising advances in diffusion models for video generation quality the complex model architecture and substantial computational demands for both training and inference create a significant gap between these models and real-world applications. This paper presents SNED a superposition network architecture search method for efficient video diffusion model. Our method employs a supernet training paradigm that targets various model cost and resolution options using a weight-sharing method. Moreover we propose the supernet training sampling warm-up for fast training optimization. To showcase the flexibility of our method we conduct experiments involving both pixel-space and latent-space video diffusion models. The results demonstrate that our framework consistently produces comparable results across different model options with high efficiency. According to the experiment for the pixel-space video diffusion model we can achieve consistent video generation results simultaneously across 64 x 64 to 256 x 256 resolutions with a large range of model sizes from 640M to 1.6B number of parameters for pixel-space video diffusion models.
Groupwise Query Specialization and Quality-Aware Multi-Assignment for Transformer-based Visual Relationship Detection
Authors: Jongha Kim, Jihwan Park, Jinyoung Park, Jinyoung Kim, Sehyung Kim, Hyunwoo J. Kim
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Visual Relationship Detection (VRD) has seen significant advancements with Transformer-based architectures recently. However we identify two key limitations in a conventional label assignment for training Transformer-based VRD models which is a process of mapping a ground-truth (GT) to a prediction. Under the conventional assignment an 'unspecialized' query is trained since a query is expected to detect every relation which makes it difficult for a query to specialize in specific relations. Furthermore a query is also insufficiently trained since a GT is assigned only to a single prediction therefore near-correct or even correct predictions are suppressed by being assigned 'no relation' as a GT. To address these issues we propose Groupwise Query Specialization and Quality-Aware Multi-Assignment (SpeaQ). Groupwise Query Specialization trains a 'specialized' query by dividing queries and relations into disjoint groups and directing a query in a specific query group solely toward relations in the corresponding relation group. Quality-Aware Multi-Assignment further facilitates the training by assigning a GT to multiple predictions that are significantly close to a GT in terms of a subject an object and the relation in between. Experimental results and analyses show that SpeaQ effectively trains 'specialized' queries which better utilize the capacity of a model resulting in consistent performance gains with 'zero' additional inference cost across multiple VRD models and benchmarks. Code is available at https://github.com/mlvlab/SpeaQ.