pwc-archive/papers-with-abstracts huggingface dataset:
Neural Fields as Distributions: Signal Processing Beyond Euclidean Space
Authors: Daniel Rebain, Soroosh Yazdani, Kwang Moo Yi, Andrea Tagliasacchi
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1

    Neural fields have emerged as a powerful and broadly applicable method for representing signals. However in contrast to classical discrete digital signal processing the portfolio of tools to process such representations is still severely limited and restricted to Euclidean domains. In this paper we address this problem by showing how a probabilistic re-interpretation of neural fields can enable their training and inference processes to become "filter-aware". The formulation we propose not only merges training and filtering in an efficient way but also generalizes beyond the familiar Euclidean coordinate spaces to the more general set of smooth manifolds and convolutions induced by the actions of Lie groups. We demonstrate how this framework can enable novel integrations of signal processing techniques for neural field applications on both Euclidean domains such as images and audio as well as non-Euclidean domains such as rotations and rays. A noteworthy benefit of our method is its applicability. Our method can be summarized as primarily a modification of the loss function and in most cases does not require changes to the network architecture or the inference process.
Improving Generalized Zero-Shot Learning by Exploring the Diverse Semantics from External Class Names
Authors: Yapeng Li, Yong Luo, Zengmao Wang, Bo Du
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Generalized Zero-Shot Learning, Test unseen, Zero-Shot Learning

    Generalized Zero-Shot Learning (GZSL) methods often assume that the unseen classes are similar to seen classes and thus perform poor when unseen classes are dissimilar to seen classes. Although some existing GZSL approaches can alleviate this issue by leveraging additional semantic information from test unseen classes their generalization ability to dissimilar unseen classes is still unsatisfactory. This motivates us to study GZSL in the more practical setting where unseen classes can be either similar or dissimilar to seen classes. In this paper we propose a simple yet effective GZSL framework by exploring diverse semantics from external class names (DSECN) which is simultaneously robust on the similar and dissimilar unseen classes. This is achieved by introducing diverse semantics from external class names and aligning the introduced semantics to visual space using the classification head of pre-trained network. Furthermore we show that the design idea of DSECN can easily be integrate into other advanced GZSL approaches such as the generative-based ones and enhance their robustness for dissimilar unseen classes. Extensive experiments in the practical setting including both similar and dissimilar unseen classes show that our method significantly outperforms the state-of-the-art approaches on all datasets and can be trained very efficiently.
Referring Expression Counting
Authors: Siyang Dai, Jun Liu, Ngai-Man Cheung
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: 8k, object-detection, Object Detection, Referring Expression

    Existing counting tasks are limited to the class level which don't account for fine-grained details within the class. In real applications it often requires in-context or referring human input for counting target objects. Take urban analysis as an example fine-grained information such as traffic flow in different directions pedestrians and vehicles waiting or moving at different sides of the junction is more beneficial. Current settings of both class-specific and class-agnostic counting treat objects of the same class indifferently which pose limitations in real use cases. To this end we propose a new task named Referring Expression Counting (REC) which aims to count objects with different attributes within the same class. To evaluate the REC task we create a novel dataset named REC-8K which contains 8011 images and 17122 referring expressions. Experiments on REC-8K show that our proposed method achieves state-of-the-art performance compared with several text-based counting methods and an open-set object detection model. We also outperform prior models on the class agnostic counting (CAC) benchmark [36] for the zero-shot setting and perform on par with the few-shot methods. Code and dataset is available at https://github.com/sydai/referring-expression-counting.
Brush2Prompt: Contextual Prompt Generator for Object Inpainting
Authors: Mang Tik Chiu, Yuqian Zhou, Lingzhi Zhang, Zhe Lin, Connelly Barnes, Sohrab Amirghodsi, Eli Shechtman, Humphrey Shi
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Diversity, Object

    Object inpainting is a task that involves adding objects to real images and seamlessly compositing them. With the recent commercialization of products like Stable Diffusion and Generative Fill inserting objects into images by using prompts has achieved impressive visual results. In this paper we propose a prompt suggestion model to simplify the process of prompt input. When the user provides an image and a mask our model predicts suitable prompts based on the partial contextual information in the masked image and the shape and location of the mask. Specifically we introduce a concept-diffusion in the CLIP space that predicts CLIP-text embeddings from a masked image. These diffused embeddings can be directly injected into open-source inpainting models like Stable Diffusion and its variants. Alternatively they can be decoded into natural language for use in other publicly available applications such as Generative Fill. Our prompt suggestion model demonstrates a balanced accuracy and diversity showing its capability to be both contextually aware and creatively adaptive.
LEAD: Exploring Logit Space Evolution for Model Selection
Authors: Zixuan Hu, Xiaotong Li, Shixiang Tang, Jun Liu, Yichun Hu, Ling-Yu Duan
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: model, Model Selection

    The remarkable success of "pretrain-then-finetune" paradigm has led to a proliferation of available pre-trained models for vision tasks. This surge presents a significant challenge in efficiently choosing the most suitable pre-trained models for downstream tasks. The critical aspect of this challenge lies in effectively predicting the model transferability by considering the underlying fine-tuning dynamics. Existing methods often model fine-tuning dynamics in feature space with linear transformations which do not precisely align with the fine-tuning objective and fail to grasp the essential nonlinearity from optimization. To this end we present LEAD a finetuning-aligned approach based on the network output of logits. LEAD proposes a theoretical framework to model the optimization process and derives an ordinary differential equation (ODE) to depict the nonlinear evolution toward the final logit state. Additionally we design a class-aware decomposition method to consider the varying evolution dynamics across classes and further ensure practical applicability. Integrating the closely aligned optimization objective and nonlinear modeling capabilities derived from the differential equation our method offers a concise solution to effectively bridge the optimization gap in a single step bypassing the lengthy fine-tuning process. The comprehensive experiments on 24 supervised and self-supervised pre-trained models across 10 downstream datasets demonstrate impressive performances and showcase its broad adaptability even in low-data scenarios.
Video Harmonization with Triplet Spatio-Temporal Variation Patterns
Authors: Zonghui Guo, Xinyu Han, Jie Zhang, Shiguang Shan, Haiyong Zheng
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Triplet, Video Enhancement, Video Harmonization

    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.
TULIP: Multi-camera 3D Precision Assessment of Parkinson's Disease
Authors: Kyungdo Kim, Sihan Lyu, Sneha Mantri, Timothy W. Dunn
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1

    Parkinson's disease (PD) is a devastating movement disorder accelerating in global prevalence but a lack of precision symptom measurement has made the development of effective therapies challenging. The Unified Parkinson's Disease Rating Scale (UPDRS) is the gold-standard for assessing motor symptom severity yet its manual scoring criteria are vague and subjective resulting in coarse and noisy clinical assessments. Machine learning approaches have the potential to modernize PD symptom assessments by making them more quantitative objective and scalable. However the lack of benchmark video datasets for PD motor exams hinders model development. Here we introduce the TULIP dataset to bridge this gap. TULIP emphasizes precision and comprehensiveness comprising multi-view video recordings (6 cameras) of all 25 UPDRS motor exam components together with ratings by 3 clinical experts in a cohort of Parkinson's patients and healthy controls. The multi-view recordings enable 3D reconstructions of body movement that better capture disease signatures than more conventional 2D methods. Using the dataset we establish a baseline model for predicting UPDRS scores from 3D poses illustrating how existing diagnostics could be automated. Looking ahead TULIP could aid the development of new precision diagnostics that transcend UPDRS scores providing a deeper understanding of PD and its potential treatments.
Density-Guided Semi-Supervised 3D Semantic Segmentation with Dual-Space Hardness Sampling
Authors: Jianan Li, Qiulei Dong
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: 3D Semantic Segmentation, Contrastive Learning, Semantic Segmentation

    Densely annotating the large-scale point clouds is laborious. To alleviate the annotation burden contrastive learning has attracted increasing attention for tackling semi-supervised 3D semantic segmentation. However existing point-to-point contrastive learning techniques in literature are generally sensitive to outliers resulting in insufficient modeling of the point-wise representations. To address this problem we propose a method named DDSemi for semi-supervised 3D semantic segmentation where a density-guided contrastive learning technique is explored. This technique calculates the contrastive loss in a point-to-anchor manner by estimating an anchor for each class from the memory bank based on the finding that the cluster centers tend to be located in dense regions. In this technique an inter-contrast loss is derived from the perturbed unlabeled point cloud pairs while an intra-contrast loss is derived from a single unlabeled point cloud. The derived losses could enhance the discriminability of the features and implicitly constrain the semantic consistency between the perturbed unlabeled point cloud pairs. In addition we propose a dual-space hardness sampling strategy to pay more attention to the hard samples located in sparse regions of both the geometric space and feature space by reweighting the point-wise intra-contrast loss. Experimental results on both indoor-scene and outdoor-scene datasets demonstrate that the proposed method outperforms the comparative state-of-the-art semi-supervised methods.
Towards Surveillance Video-and-Language Understanding: New Dataset Baselines and Challenges
Authors: Tongtong Yuan, Xuange Zhang, Kun Liu, Bo Liu, Chen Chen, Jian Jin, Zhenzhen Jiao
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Anomaly Detection

    Surveillance videos are important for public security. However current surveillance video tasks mainly focus on classifying and localizing anomalous events. Existing methods are limited to detecting and classifying the predefined events with unsatisfactory semantic understanding although they have obtained considerable performance. To address this issue we propose a new research direction of surveillance video-and-language understanding(VALU) and construct the first multimodal surveillance video dataset. We manually annotate the real-world surveillance dataset UCF-Crime with fine-grained event content and timing. Our newly annotated dataset UCA (UCF-Crime Annotation) contains 23542 sentences with an average length of 20 words and its annotated videos are as long as 110.7 hours. Furthermore we benchmark SOTA models for four multimodal tasks on this newly created dataset which serve as new baselines for surveillance VALU. Through experiments we find that mainstream models used in previously public datasets perform poorly on surveillance video demonstrating new challenges in surveillance VALU. We also conducted experiments on multimodal anomaly detection. These results demonstrate that our multimodal surveillance learning can improve the performance of anomaly detection. All the experiments highlight the necessity of constructing this dataset to advance surveillance AI.
SaCo Loss: Sample-wise Affinity Consistency for Vision-Language Pre-training
Authors: Sitong Wu, Haoru Tan, Zhuotao Tian, Yukang Chen, Xiaojuan Qi, Jiaya Jia
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1

    Vision-language pre-training (VLP) aims to learn joint representations of vision and language modalities. The contrastive paradigm is currently dominant in this field. However we observe a notable misalignment phenomenon that is the affinity between samples has an obvious disparity across different modalities namely "Affinity Inconsistency Problem". Our intuition is that for a well-aligned model two images that look similar to each other should have the same level of similarity as their corresponding texts that describe them. In this paper we first investigate the reason of this inconsistency problem. We discover that the lack of consideration for sample-wise affinity consistency across modalities in existing training objectives is the central cause. To address this problem we propose a novel loss function named Sample-wise affinity Consistency (SaCo) loss which is designed to enhance such consistency by minimizing the distance between image embedding similarity and text embedding similarity for any two samples. Our SaCo loss can be easily incorporated into existing vision-language models as an additional loss due to its complementarity for most training objectives. In addition considering that pre-training from scratch is computationally expensive we also provide a more efficient way to continuously pre-train on a converged model by integrating our loss. Experimentally the model trained with our SaCo loss significantly outperforms the baseline on a variety of vision and language tasks.
Omni-Q: Omni-Directional Scene Understanding for Unsupervised Visual Grounding
Authors: Sai Wang, Yutian Lin, Yu Wu
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Scene Understanding, Visual Grounding

    Unsupervised visual grounding methods alleviate the issue of expensive manual annotation of image-query pairs by generating pseudo-queries. However existing methods are prone to confusing the spatial relationships between objects and rely on designing complex prompt modules to generate query texts which severely impedes the ability to generate accurate and comprehensive queries due to ambiguous spatial relationships and manually-defined fixed templates. To tackle these challenges we propose a omni-directional language query generation approach for unsupervised visual grounding named Omni-Q. Specifically we develop a 3D spatial relation module to extend the 2D spatial representation to 3D thereby utilizing 3D location information to accurately determine the spatial position among objects. Besides we introduce a spatial graph module leveraging the power of graph structures to establish accurate and diverse object relationships and thus enhancing the flexibility of query generation. Extensive experiments on five public benchmark datasets demonstrate that our method significantly outperforms existing state-of-the-art unsupervised methods by up to 16.17%. In addition when applied in the supervised setting our method can freely save up to 60% human annotations without a loss of performance.
Compositional Video Understanding with Spatiotemporal Structure-based Transformers
Authors: Hoyeoung Yun, Jinwoo Ahn, Minseo Kim, Eun-Sol Kim
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Video Understanding

    In this paper we suggest a new novel method to understand complex semantic structures through long video inputs. Conventional methods for understanding videos have been focused on short-term clips and trained to get visual representations for the short clips using convolutional neural networks or transformer architectures. However most real-world videos are composed of long videos ranging from minutes to hours therefore it essentially brings limitations to understanding the overall semantic structures of the long videos by dividing them into small clips and learning the representations of them. We suggest a new algorithm to learn the multi-granular semantic structures of videos by defining spatiotemporal high-order relationships among object-based representations as semantic units. The proposed method includes a new transformer architecture capable of learning spatiotemporal graphs and a compositional learning method to learn disentangled features for each semantic unit. Using the suggested method we resolve the challenging video task which is compositional generalization understanding of unseen videos. In experiments we demonstrate new state-of-the-art performances for two challenging video datasets.
HDQMF: Holographic Feature Decomposition Using Quantum Algorithms
Authors: Prathyush Prasanth Poduval, Zhuowen Zou, Mohsen Imani
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1

    This paper addresses the decomposition of holographic feature vectors in Hyperdimensional Computing (HDC) aka Vector Symbolic Architectures (VSA). HDC uses high-dimensional vectors with brain-like properties to represent symbolic information and leverages efficient operators to construct and manipulate complexly structured data in a cognitive fashion. Existing models face challenges in decomposing these structures a process crucial for understanding and interpreting a composite hypervector. We address this challenge by proposing the HDC Memorized-Factorization Problem that captures the common patterns of construction in HDC models. To solve this problem efficiently we introduce HDQMF a HyperDimensional Quantum Memorized-Factorization algorithm. HDQMF is unique in its approach utilizing quantum computing to offer efficient solutions. It modifies crucial steps in Grover's algorithm to achieve hypervector decomposition achieving quadratic speed-up.
CrossMAE: Cross-Modality Masked Autoencoders for Region-Aware Audio-Visual Pre-Training
Authors: Yuxin Guo, Siyang Sun, Shuailei Ma, Kecheng Zheng, Xiaoyi Bao, Shijie Ma, Wei Zou, Yun Zheng
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1

    Learning joint and coordinated features across modalities is essential for many audio-visual tasks. Existing pre-training methods primarily focus on global information neglecting fine-grained features and positions leading to suboptimal performance in dense prediction tasks. To address this issue we take a further step towards region-aware audio-visual pre-training and propose CrossMAE which excels in Cross-modality interaction and region alignment. Specifically we devise two masked autoencoding (MAE) pretext tasks at both pixel and embedding levels namely Cross-Conditioned Reconstruction and Cross-Embedding Reconstruction. Taking the visual modality as an example (the same goes for audio) in Cross-Conditioned Reconstruction the visual modality reconstructs the input image pixels conditioned on audio Attentive Tokens. As for the more challenging Cross-Embedding Reconstruction unmasked visual tokens reconstruct complete audio features under the guidance of learnable queries implying positional information which effectively enhances the interaction between modalities and exploits fine-grained semantics. Experimental results demonstrate that CrossMAE achieves state-of-the-art performance not only in classification and retrieval but also in dense prediction tasks. Furthermore we dive into the mechanism of modal interaction and region alignment of CrossMAE highlighting the effectiveness of the proposed components.
Real-Time Exposure Correction via Collaborative Transformations and Adaptive Sampling
Authors: Ziwen Li, Feng Zhang, Meng Cao, Jinpu Zhang, Yuanjie Shao, Yuehuan Wang, Nong Sang
Date: 2024-01-01 00:00:00
Proceeding: CVPR 2024 1
Tasks: Exposure Correction, Image Enhancement

    Most of the previous exposure correction methods learn dense pixel-wise transformations to achieve promising results but consume huge computational resources. Recently Learnable 3D lookup tables (3D LUTs) have demonstrated impressive performance and efficiency for image enhancement. However these methods can only perform global transformations and fail to finely manipulate local regions. Moreover they uniformly downsample the input image which loses the rich color information and limits the learning of color transformation capabilities. In this paper we present a collaborative transformation framework (CoTF) for real-time exposure correction which integrates global transformation with pixel-wise transformations in an efficient manner. Specifically the global transformation adjusts the overall appearance using image-adaptive 3D LUTs to provide decent global contrast and sharp details while the pixel transformation compensates for local context. Then a relation-aware modulation module is designed to combine these two components effectively. In addition we propose an adaptive sampling strategy to preserve more color information by predicting the sampling intervals thus providing higher quality input data for the learning of 3D LUTs. Extensive experiments demonstrate that our method can process high-resolution images in real-time on GPUs while achieving comparable performance against current state-of-the-art methods. The code is available at https://github.com/HUST-IAL/CoTF.