mtybilly/Instruct2DS huggingface dataset:
From SAM to CAMs: Exploring Segment Anything Model for Weakly Supervised Semantic Segmentation
Authors: Kuk-Jin Yoon Hyeokjun Kweon
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Weakly Supervised Semantic Segmentation (WSSS) aims to learn the concept of segmentation using image-level class labels. Recent WSSS works have shown promising results by using the Segment Anything Model (SAM) a foundation model for segmentation during the inference phase. However we observe that these methods can still be vulnerable to the noise of class activation maps (CAMs) serving as initial seeds. As a remedy this paper introduces From-SAM-to-CAMs (S2C) a novel WSSS framework that directly transfers the knowledge of SAM to the classifier during the training process enhancing the quality of CAMs itself. S2C comprises SAM-segment Contrasting (SSC) and a CAM-based prompting module (CPM) which exploit SAM at the feature and logit levels respectively. SSC performs prototype-based contrasting using SAM's automatic segmentation results. It constrains each feature to be close to the prototype of its segment and distant from prototypes of the others. Meanwhile CPM extracts prompts from the CAM of each class and uses them to generate class-specific segmentation masks through SAM. The masks are aggregated into unified self-supervision based on the confidence score designed to consider the reliability of both SAM and CAMs. S2C achieves a new state-of-the-art performance across all benchmarks outperforming existing studies by significant margins. The code is available at https://github.com/sangrockEG/S2C.
Boosting Flow-based Generative Super-Resolution Models via Learned Prior
Authors: Yi-Chen Lo, Chia-Che Chang, Hao-Wei Chen, Roy Tseng, Chien Feng, Chun-Yi Lee Li-Yuan Tsao
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Flow-based super-resolution (SR) models have demonstrated astonishing capabilities in generating high-quality images. However these methods encounter several challenges during image generation such as grid artifacts exploding inverses and suboptimal results due to a fixed sampling temperature. To overcome these issues this work introduces a conditional learned prior to the inference phase of a flow-based SR model. This prior is a latent code predicted by our proposed latent module conditioned on the low-resolution image which is then transformed by the flow model into an SR image. Our framework is designed to seamlessly integrate with any contemporary flow-based SR model without modifying its architecture or pre-trained weights. We evaluate the effectiveness of our proposed framework through extensive experiments and ablation analyses. The proposed framework successfully addresses all the inherent issues in flow-based SR models and enhances their performance in various SR scenarios. Our code is available at: https://github.com/liyuantsao/FlowSR-LP
How to Handle Sketch-Abstraction in Sketch-Based Image Retrieval?
Authors: Ayan Kumar Bhunia, Aneeshan Sain, Pinaki Nath Chowdhury, Tao Xiang, Yi-Zhe Song Subhadeep Koley
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In this paper we propose a novel abstraction-aware sketch-based image retrieval framework capable of handling sketch abstraction at varied levels. Prior works had mainly focused on tackling sub-factors such as drawing style and order we instead attempt to model abstraction as a whole and propose feature-level and retrieval granularity-level designs so that the system builds into its DNA the necessary means to interpret abstraction. On learning abstraction-aware features we for the first-time harness the rich semantic embedding of pre-trained StyleGAN model together with a novel abstraction-level mapper that deciphers the level of abstraction and dynamically selects appropriate dimensions in the feature matrix correspondingly to construct a feature matrix embedding that can be freely traversed to accommodate different levels of abstraction. For granularity-level abstraction understanding we dictate that the retrieval model should not treat all abstraction-levels equally and introduce a differentiable surrogate Acc.@q loss to inject that understanding into the system. Different to the gold-standard triplet loss our Acc.@q loss uniquely allows a sketch to narrow/broaden its focus in terms of how stringent the evaluation should be - the more abstract a sketch the less stringent (higher q). Extensive experiments depict our method to outperform existing state-of-the-arts in standard SBIR tasks along with challenging scenarios like early retrieval forensic sketch-photo matching and style-invariant retrieval.
What You See is What You GAN: Rendering Every Pixel for High-Fidelity Geometry in 3D GANs
Authors: Matthew Chan, Towaki Takikawa, Umar Iqbal, Shalini De Mello, Manmohan Chandraker, Ravi Ramamoorthi, Koki Nagano Alex Trevithick
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: 3D-aware Generative Adversarial Networks (GANs) have shown remarkable progress in learning to generate multi-view-consistent images and 3D geometries of scenes from collections of 2D images via neural volume rendering. Yet the significant memory and computational costs of dense sampling in volume rendering have forced 3D GANs to adopt patch-based training or employ low-resolution rendering with post-processing 2D super resolution which sacrifices multiview consistency and the quality of resolved geometry. Consequently 3D GANs have not yet been able to fully resolve the rich 3D geometry present in 2D images. In this work we propose techniques to scale neural volume rendering to the much higher resolution of native 2D images thereby resolving fine-grained 3D geometry with unprecedented detail. Our approach employs learning-based samplers for accelerating neural rendering for 3D GAN training using up to 5 times fewer depth samples. This enables us to explicitly "render every pixel" of the full-resolution image during training and inference without post-processing superresolution in 2D. Together with our strategy to learn high-quality surface geometry our method synthesizes high-resolution 3D geometry and strictly view-consistent images while maintaining image quality on par with baselines relying on post-processing super resolution. We demonstrate state-of-the-art 3D gemetric quality on FFHQ and AFHQ setting a new standard for unsupervised learning of 3D shapes in 3D GANs.
Style Injection in Diffusion: A Training-free Approach for Adapting Large-scale Diffusion Models for Style Transfer
Authors: Sangeek Hyun, Jae-Pil Heo Jiwoo Chung
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Despite the impressive generative capabilities of diffusion models existing diffusion model-based style transfer methods require inference-stage optimization (e.g. fine-tuning or textual inversion of style) which is time-consuming or fails to leverage the generative ability of large-scale diffusion models. To address these issues we introduce a novel artistic style transfer method based on a pre-trained large-scale diffusion model without any optimization. Specifically we manipulate the features of self-attention layers as the way the cross-attention mechanism works; in the generation process substituting the key and value of content with those of style image. This approach provides several desirable characteristics for style transfer including 1) preservation of content by transferring similar styles into similar image patches and 2) transfer of style based on similarity of local texture (e.g. edge) between content and style images. Furthermore we introduce query preservation and attention temperature scaling to mitigate the issue of disruption of original content and initial latent Adaptive Instance Normalization (AdaIN) to deal with the disharmonious color (failure to transfer the colors of style). Our experimental results demonstrate that our proposed method surpasses state-of-the-art methods in both conventional and diffusion-based style transfer baselines.
Towards Robust Learning to Optimize with Theoretical Guarantees
Authors: Wei Lin, Juncheng Wang, Hong Xu Qingyu Song
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Learning to optimize (L2O) is an emerging technique to solve mathematical optimization problems with learning-based methods. Although with great success in many real-world scenarios such as wireless communications computer networks and electronic design existing L2O works lack theoretical demonstration of their performance and robustness in out-of-distribution (OOD) scenarios. We address this gap by providing comprehensive proofs. First we prove a sufficient condition for a robust L2O model with homogeneous convergence rates over all In-Distribution (InD) instances. We assume an L2O model achieves robustness for an InD scenario. Based on our proposed methodology of aligning OOD problems to InD problems we also demonstrate that the L2O model's convergence rate in OOD scenarios will deteriorate by an equation of the L2O model's input features. Moreover we propose an L2O model with a concise gradient-only feature construction and a novel gradient-based history modeling method. Numerical simulation demonstrates that our proposed model outperforms the state-of-the-art baseline in both InD and OOD scenarios and achieves up to 10 xconvergence speedup. The code of our method can be found from https://github.com/NetX-lab/GoMathL2O-Official.
Differentiable Neural Surface Refinement for Modeling Transparent Objects
Authors: Dylan Campbell, Chunyi Sun, Shubham Kanitkar, Matthew E. Shaffer, Stephen Gould Weijian Deng
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Neural implicit surface reconstruction leveraging volume rendering has led to significant advances in multi-view reconstruction. However results for transparent objects can be very poor primarily because the rendering function fails to account for the intricate light transport induced by refraction and reflection. In this study we introduce transparent neural surface refinement (TNSR) a novel surface reconstruction framework that explicitly incorporates physical refraction and reflection tracing. Beginning with an initial approximate surface our method employs sphere tracing combined with Snell's law to cast both reflected and refracted rays. Central to our proposal is an innovative differentiable technique devised to allow signals from the photometric evidence to propagate back to the surface model by considering how the surface bends and reflects light rays. This allows us to connect surface refinement with volume rendering enabling end-to-end optimization solely on multi-view RGB images. In our experiments TNSR demonstrates significant improvements in novel view synthesis and geometry estimation of transparent objects without prior knowledge of the refractive index.
OrthCaps: An Orthogonal CapsNet with Sparse Attention Routing and Pruning
Authors: Jiaming Wang, Jiawei Gong, Yuerong Xue, Jun Xu, Fanglin Chen, Xiaolin Huang Xinyu Geng
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Redundancy is a persistent challenge in Capsule Networks (CapsNet) leading to high computational costs and parameter counts. Although previous studies have introduced pruning after the initial capsule layer dynamic routing's fully connected nature and non-orthogonal weight matrices reintroduce redundancy in deeper layers. Besides dynamic routing requires iterating to converge further increasing computational demands. In this paper we propose an Orthogonal Capsule Network (OrthCaps) to reduce redundancy improve routing performance and decrease parameter counts. Firstly an efficient pruned capsule layer is introduced to discard redundant capsules. Secondly dynamic routing is replaced with orthogonal sparse attention routing eliminating the need for iterations and fully connected structures. Lastly weight matrices during routing are orthogonalized to sustain low capsule similarity which is the first approach to use Householder orthogonal decomposition to enforce orthogonality in CapsNet. Our experiments on baseline datasets affirm the efficiency and robustness of OrthCaps in classification tasks in which ablation studies validate the criticality of each component. OrthCaps-Shallow outperforms other Capsule Network benchmarks on four datasets utilizing only 110k parameters - a mere 1.25% of a standard Capsule Network's total. To the best of our knowledge it achieves the smallest parameter count among existing Capsule Networks. Similarly OrthCaps-Deep demonstrates competitive performance across four datasets utilizing only 1.2% of the parameters required by its counterparts.
ProS: Prompting-to-simulate Generalized knowledge for Universal Cross-Domain Retrieval
Authors: Jingkuan Song, Lianli Gao, Pengpeng Zeng, Zhi-Qi Cheng, Xiyao Li, Heng Tao Shen Kaipeng Fang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: The goal of Universal Cross-Domain Retrieval (UCDR) is to achieve robust performance in generalized test scenarios wherein data may belong to strictly unknown domains and categories during training. Recently pre-trained models with prompt tuning have shown strong generalization capabilities and attained noteworthy achievements in various downstream tasks such as few-shot learning and video-text retrieval. However applying them directly to UCDR may not be sufficient to handle both domain shift (i.e. adapting to unfamiliar domains) and semantic shift (i.e. transferring to unknown categories). To this end we propose Prompting-to-Simulate (ProS) the first method to apply prompt tuning for UCDR. ProS employs a two-step process to simulate Content-aware Dynamic Prompts (CaDP) which can impact models to produce generalized features for UCDR. Concretely in Prompt Units Learning stage we introduce two Prompt Units to individually capture domain and semantic knowledge in a mask-and-align way. Then in Context-aware Simulator Learning stage we train a Content-aware Prompt Simulator under a simulated test scenario to produce the corresponding CaDP. Extensive experiments conducted on three benchmark datasets show that our method achieves new state-of-the-art performance without bringing excessive parameters. Code is available at https://github.com/fangkaipeng/ProS
Florence-2: Advancing a Unified Representation for a Variety of Vision Tasks
Authors: Haiping Wu, Weijian Xu, Xiyang Dai, Houdong Hu, Yumao Lu, Michael Zeng, Ce Liu, Lu Yuan Bin Xiao
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: We introduce Florence-2 a novel vision foundation model with a unified prompt-based representation for various computer vision and vision-language tasks. While existing large vision models excel in transfer learning they struggle to perform diverse tasks with simple instructions a capability that implies handling the complexity of various spatial hierarchy and semantic granularity. Florence-2 was designed to take text-prompt as task instructions and generate desirable results in text forms whether it be captioning object detection grounding or segmentation. This multi-task learning setup demands large-scale high-quality annotated data. To this end we co-developed FLD-5B that consists of 5.4 billion comprehensive visual annotations on 126 million images using an iterative strategy of automated image annotation and model refinement. We adopted a sequence-to-sequence structure to train Florence-2 to perform versatile and comprehensive vision tasks. Extensive evaluations on numerous tasks demonstrated Florence-2 to be a strong vision foundation model contender with unprecedented zero-shot and fine-tuning capabilities.
NeRF On-the-go: Exploiting Uncertainty for Distractor-free NeRFs in the Wild
Authors: Zihan Zhu, Boyang Sun, Jiaqi Chen, Marc Pollefeys, Songyou Peng Weining Ren
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Neural Radiance Fields (NeRFs) have shown remarkable success in synthesizing photorealistic views from multi-view images of static scenes but face challenges in dynamic real-world environments with distractors like moving objects shadows and lighting changes. Existing methods manage controlled environments and low occlusion ratios but fall short in render quality especially under high occlusion scenarios. In this paper we introduce NeRF On-the-go a simple yet effective approach that enables the robust synthesis of novel views in complex in-the-wild scenes from only casually captured image sequences. Delving into uncertainty our method not only efficiently eliminates distractors even when they are predominant in captures but also achieves a notably faster convergence speed. Through comprehensive experiments on various scenes our method demonstrates a significant improvement over state-of-the-art techniques. This advancement opens new avenues for NeRF in diverse and dynamic real-world applications.
3D Human Pose Perception from Egocentric Stereo Videos
Authors: Jian Wang, Vladislav Golyanik, Christian Theobalt Hiroyasu Akada
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: While head-mounted devices are becoming more compact they provide egocentric views with significant self-occlusions of the device user. Hence existing methods often fail to accurately estimate complex 3D poses from egocentric views. In this work we propose a new transformer-based framework to improve egocentric stereo 3D human pose estimation which leverages the scene information and temporal context of egocentric stereo videos. Specifically we utilize 1) depth features from our 3D scene reconstruction module with uniformly sampled windows of egocentric stereo frames and 2) human joint queries enhanced by temporal features of the video inputs. Our method is able to accurately estimate human poses even in challenging scenarios such as crouching and sitting. Furthermore we introduce two new benchmark datasets i.e. UnrealEgo2 and UnrealEgo-RW (RealWorld). UnrealEgo2 is a large-scale in-the-wild dataset captured in synthetic 3D scenes. UnrealEgo-RW is a real-world dataset captured with our newly developed device. The proposed datasets offer a much larger number of egocentric stereo views with a wider variety of human motions than the existing datasets allowing comprehensive evaluation of existing and upcoming methods. Our extensive experiments show that the proposed approach significantly outperforms previous methods. UnrealEgo2 UnrealEgo-RW and trained models are available on our project page and Benchmark Challenge.
Grid Diffusion Models for Text-to-Video Generation
Authors: Soyeong Kwon, Taehwan Kim Taegyeong Lee
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Recent advances in the diffusion models have significantly improved text-to-image generation. However generating videos from text is a more challenging task than generating images from text due to the much larger dataset and higher computational cost required. Most existing video generation methods use either a 3D U-Net architecture that considers the temporal dimension or autoregressive generation. These methods require large datasets and are limited in terms of computational costs compared to text-to-image generation. To tackle these challenges we propose a simple but effective novel grid diffusion for text-to-video generation without temporal dimension in architecture and a large text-video paired dataset. We can generate a high-quality video using a fixed amount of GPU memory regardless of the number of frames by representing the video as a grid image. Additionally since our method reduces the dimensions of the video to the dimensions of the image various image-based methods can be applied to videos such as text-guided video manipulation from image manipulation. Our proposed method outperforms the existing methods in both quantitative and qualitative evaluations demonstrating the suitability of our model for real-world video generation.
Boosting Object Detection with Zero-Shot Day-Night Domain Adaptation
Authors: Miaojing Shi, Jiankang Deng Zhipeng Du
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Detecting objects in low-light scenarios presents a persistent challenge as detectors trained on well-lit data exhibit significant performance degradation on low-light data due to low visibility. Previous methods mitigate this issue by exploring image enhancement or object detection techniques with real low-light image datasets. However the progress is impeded by the inherent difficulties about collecting and annotating low-light images. To address this challenge we propose to boost low-light object detection with zero-shot day-night domain adaptation which aims to generalize a detector from well-lit scenarios to low-light ones without requiring real low-light data. Revisiting Retinex theory in the low-level vision we first design a reflectance representation learning module to learn Retinex-based illumination invariance in images with a carefully designed illumination invariance reinforcement strategy. Next an interchange-redecomposition-coherence procedure is introduced to improve over the vanilla Retinex image decomposition process by performing two sequential image decompositions and introducing a redecomposition cohering loss. Extensive experiments on ExDark DARK FACE and CODaN datasets show strong low-light generalizability of our method. Our code is available at https://github.com/ZPDu/DAI-Net.
LucidDreamer: Towards High-Fidelity Text-to-3D Generation via Interval Score Matching
Authors: Xin Yang, Jiantao Lin, Haodong Li, Xiaogang Xu, Yingcong Chen Yixun Liang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: The recent advancements in text-to-3D generation mark a significant milestone in generative models unlocking new possibilities for creating imaginative 3D assets across various real-world scenarios. While recent advancements in text-to-3D generation have shown promise they often fall short in rendering detailed and high-quality 3D models. This problem is especially prevalent as many methods base themselves on Score Distillation Sampling (SDS). This paper identifies a notable deficiency in SDS that it brings inconsistent and low-quality updating direction for the 3D model causing the over-smoothing effect. To address this we propose a novel approach called Interval Score Matching (ISM). ISM employs deterministic diffusing trajectories and utilizes interval-based score matching to counteract over-smoothing. Furthermore we incorporate 3D Gaussian Splatting into our text-to-3D generation pipeline. Extensive experiments show that our model largely outperforms the state-of-the-art in quality and training efficiency.
PTM-VQA: Efficient Video Quality Assessment Leveraging Diverse PreTrained Models from the Wild
Authors: Hongbo Liu, Mading Li, Muyi Sun, Ming Sun, Jiachao Gong, Jinhua Hao, Chao Zhou, Yansong Tang Kun Yuan
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Video quality assessment (VQA) is a challenging problem due to the numerous factors that can affect the perceptual quality of a video e.g. content attractiveness distortion type motion pattern and level. However annotating the Mean opinion score (MOS) for videos is expensive and time-consuming which limits the scale of VQA datasets and poses a significant obstacle for deep learning-based methods. In this paper we propose a VQA method named PTM-VQA which leverages PreTrained Models to transfer knowledge from models pretrained on various pre-tasks enabling benefits for VQA from different aspects. Specifically we extract features of videos from different pretrained models with frozen weights and integrate them to generate representation. Since these models possess various fields of knowledge and are often trained with labels irrelevant to quality we propose an Intra-Consistency and Inter-Divisibility (ICID) loss to impose constraints on features extracted by multiple pretrained models. The intra-consistency constraint ensures that features extracted by different pretrained models are in the same unified quality-aware latent space while the inter-divisibility introduces pseudo clusters based on the annotation of samples and tries to separate features of samples from different clusters. Furthermore with a constantly growing number of pretrained models it is crucial to determine which models to use and how to use them. To address this problem we propose an efficient scheme to select suitable candidates. Models with better clustering performance on VQA datasets are chosen to be our candidates. Extensive experiments demonstrate the effectiveness of the proposed method.
Versatile Medical Image Segmentation Learned from Multi-Source Datasets via Model Self-Disambiguation
Authors: Hao Zheng, Yuemeng Li, Yuncong Ma, Liang Ma, Hongming Li, Yong Fan Xiaoyang Chen
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: A versatile medical image segmentation model applicable to images acquired with diverse equipment and protocols can facilitate model deployment and maintenance. However building such a model typically demands a large diverse and fully annotated dataset which is challenging to obtain due to the labor-intensive nature of data curation. To address this challenge we propose a cost-effective alternative that harnesses multi-source data with only partial or sparse segmentation labels for training substantially reducing the cost of developing a versatile model. We devise strategies for model self-disambiguation prior knowledge incorporation and imbalance mitigation to tackle challenges associated with inconsistently labeled multi-source data including label ambiguity and modality dataset and class imbalances. Experimental results on a multi-modal dataset compiled from eight different sources for abdominal structure segmentation have demonstrated the effectiveness and superior performance of our method compared to state-of-the-art alternative approaches. We anticipate that its cost-saving features which optimize the utilization of existing annotated data and reduce annotation efforts for new data will have a significant impact in the field.
Improving Generalization via Meta-Learning on Hard Samples
Authors: Arun S. Suggala, Pradeep Shenoy Nishant Jain
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Learned reweighting (LRW) approaches to supervised learning use an optimization criterion to assign weights for training instances in order to maximize performance on a representative validation dataset. We pose and formalize the problem of optimized selection of the validation set used in LRW training to improve classifier generalization. In particular we show that using hard-to-classify instances in the validation set has both a theoretical connection to and strong empirical evidence of generalization. We provide an efficient algorithm for training this meta-optimized model as well as a simple train-twice heuristic for careful comparative study. We demonstrate that LRW with easy validation data performs consistently worse than LRW with hard validation data establishing the validity of our meta-optimization problem. Our proposed algorithm outperforms a wide range of baselines on a range of datasets and domain shift challenges (Imagenet-1K CIFAR-100 Clothing-1M CAMELYON WILDS etc.) with  1% gains using VIT-B on Imagenet. We also show that using naturally hard examples for validation (Imagenet-R / Imagenet-A) in LRW training for Imagenet improves performance on both clean and naturally hard test instances by 1-2%. Secondary analyses show that using hard validation data in an LRW framework improves margins on test data hinting at the mechanism underlying our empirical gains. We believe this work opens up new research directions for the meta-optimization of meta-learning in a supervised learning context.
Align and Aggregate: Compositional Reasoning with Video Alignment and Answer Aggregation for Video Question-Answering
Authors: Jiangtong Li, Li Niu, Liqing Zhang Zhaohe Liao
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Despite the recent progress made in Video Question-Answering (VideoQA) these methods typically function as black-boxes making it difficult to understand their reasoning processes and perform consistent compositional reasoning. To address these challenges we propose a model-agnostic Video Alignment and Answer Aggregation (VA3) framework which is capable of enhancing both compositional consistency and accuracy of existing VidQA methods by integrating video aligner and answer aggregator modules. The video aligner hierarchically selects the relevant video clips based on the question while the answer aggregator deduces the answer to the question based on its sub-questions with compositional consistency ensured by the information flow along the question decompose graph and the contrastive learning strategy. We evaluate our framework on three settings of the AGQA-Decomp dataset with three baseline methods and propose new metrics to measure the compositional consistency of VidQA methods more comprehensively. Moreover we propose a large language model (LLM) based automatic question decompose pipeline to apply our framework on any VidQA data. We extend MSVD and NExT-QA datasets with it to evaluate such scheme and our VA3 framework on broader scenarios. Extensive experiments show that our framework improves both compositional consistency and accuracy of existing methods leading to more interpretable models in real-world applications.
REACTO: Reconstructing Articulated Objects from a Single Video
Authors: Jiacheng Wei, Chuan Sheng Foo, Guosheng Lin, Fayao Liu Chaoyue Song
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In this paper we address the challenge of reconstructing general articulated 3D objects from a single video. Existing works employing dynamic neural radiance fields have advanced the modeling of articulated objects like humans and animals from videos but face challenges with piece-wise rigid general articulated objects due to limitations in their deformation models. To tackle this we propose Quasi-Rigid Blend Skinning a novel deformation model that enhances the rigidity of each part while maintaining flexible deformation of the joints. Our primary insight combines three distinct approaches: 1) an enhanced bone rigging system for improved component modeling 2) the use of quasi-sparse skinning weights to boost part rigidity and reconstruction fidelity and 3) the application of geodesic point assignment for precise motion and seamless deformation. Our method outperforms previous works in producing higher-fidelity 3D reconstructions of general articulated objects as demonstrated on both real and synthetic datasets. Project page: https://chaoyuesong.github.io/REACTO.
Egocentric Whole-Body Motion Capture with FisheyeViT and Diffusion-Based Motion Refinement
Authors: Zhe Cao, Diogo Luvizon, Lingjie Liu, Kripasindhu Sarkar, Danhang Tang, Thabo Beeler, Christian Theobalt Jian Wang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In this work we explore egocentric whole-body motion capture using a single fisheye camera which simultaneously estimates human body and hand motion. This task presents significant challenges due to three factors: the lack of high-quality datasets fisheye camera distortion and human body self-occlusion. To address these challenges we propose a novel approach that leverages FisheyeViT to extract fisheye image features which are subsequently converted into pixel-aligned 3D heatmap representations for 3D human body pose prediction. For hand tracking we incorporate dedicated hand detection and hand pose estimation networks for regressing 3D hand poses. Finally we develop a diffusion-based whole-body motion prior model to refine the estimated whole-body motion while accounting for joint uncertainties. To train these networks we collect a large synthetic dataset EgoWholeBody comprising 840000 high-quality egocentric images captured across a diverse range of whole-body motion sequences. Quantitative and qualitative evaluations demonstrate the effectiveness of our method in producing high-quality whole-body motion estimates from a single egocentric camera.
Language Embedded 3D Gaussians for Open-Vocabulary Scene Understanding
Authors: Miao Wang, Hao-Bin Duan, Shao-Hua Guan Jin-Chuan Shi
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Open-vocabulary querying in 3D space is challenging but essential for scene understanding tasks such as object localization and segmentation. Language-embedded scene representations have made progress by incorporating language features into 3D spaces. However their efficacy heavily depends on neural networks that are resource-intensive in training and rendering. Although recent 3D Gaussians offer efficient and high-quality novel view synthesis directly embedding language features in them leads to prohibitive memory usage and decreased performance. In this work we introduce Language Embedded 3D Gaussians a novel scene representation for open-vocabulary query tasks. Instead of embedding high-dimensional raw semantic features on 3D Gaussians we propose a dedicated quantization scheme that drastically alleviates the memory requirement and a novel embedding procedure that achieves smoother yet high accuracy query countering the multi-view feature inconsistencies and the high-frequency inductive bias in point-based representations. Our comprehensive experiments show that our representation achieves the best visual quality and language querying accuracy across current language-embedded representations while maintaining real-time rendering frame rates on a single desktop GPU.
Towards Automated Movie Trailer Generation
Authors: Mattia Soldan, Alejandro Pardo, Chen Zhao, Fabian Caba Heilbron, Joon Son Chung, Bernard Ghanem Dawit Mureja Argaw
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Movie trailers are an essential tool for promoting films and attracting audiences. However the process of creating trailers can be time-consuming and expensive. To streamline this process we propose an automatic trailer generation framework that generates plausible trailers from a full movie by automating shot selection and composition. Our approach draws inspiration from machine translation techniques and models the movies and trailers as sequences of shots thus formulating the trailer generation problem as a sequence-to-sequence task. We introduce Trailer Generation Transformer (TGT) a deep-learning framework utilizing an encoder-decoder architecture. TGT movie encoder is tasked with contextualizing each movie shot representation via self-attention while the autoregressive trailer decoder predicts the feature representation of the next trailer shot accounting for the relevance of shots' temporal order in trailers. Our TGT significantly outperforms previous methods on a comprehensive suite of metrics.
Differentiable Information Bottleneck for Deterministic Multi-view Clustering
Authors: Zhixiang Jin, Fengshou Han, Yangdong Ye Xiaoqiang Yan
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In recent several years the information bottleneck (IB) principle provides an information-theoretic framework for deep multi-view clustering (MVC) by compressing multi-view observations while preserving the relevant information of multiple views. Although existing IB-based deep MVC methods have achieved huge success they rely on variational approximation and distribution assumption to estimate the lower bound of mutual information which is a notoriously hard and impractical problem in high-dimensional multi-view spaces. In this work we propose a new differentiable information bottleneck (DIB) method which provides a deterministic and analytical MVC solution by fitting the mutual information without the necessity of variational approximation. Specifically we first propose to directly fit the mutual information of high-dimensional spaces by leveraging normalized kernel Gram matrix which does not require any auxiliary neural estimator to estimate the lower bound of mutual information. Then based on the new mutual information measurement a deterministic multi-view neural network with analytical gradients is explicitly trained to parameterize IB principle which derives a deterministic compression of input variables from different views. Finally a triplet consistency discovery mechanism is devised which is capable of mining the feature consistency cluster consistency and joint consistency based on the deterministic and compact representations. Extensive experimental results show the superiority of our DIB method on 6 benchmarks compared with 13 state-of-the-art baselines.
Sheared Backpropagation for Fine-tuning Foundation Models
Authors: Li Shen, Liang Ding, Xinmei Tian, Yixin Chen, Dacheng Tao Zhiyuan Yu
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Fine-tuning is the process of extending the training of pre-trained models on specific target tasks thereby significantly enhancing their performance across various applications. However fine-tuning often demands large memory consumption posing a challenge for low-memory devices that some previous memory-efficient fine-tuning methods attempted to mitigate by pruning activations for gradient computation albeit at the cost of significant computational overhead from the pruning processes during training. To address these challenges we introduce PreBackRazor a novel activation pruning scheme offering both computational and memory efficiency through a sparsified backpropagation strategy which judiciously avoids unnecessary activation pruning and storage and gradient computation. Before activation pruning our approach samples a probability of selecting a portion of parameters to freeze utilizing a bandit method for updates to prioritize impactful gradients on convergence. During the feed-forward pass each model layer adjusts adaptively based on parameter activation status obviating the need for sparsification and storage of redundant activations for subsequent backpropagation. Benchmarking on fine-tuning foundation models our approach maintains baseline accuracy across diverse tasks yielding over 20% speedup and around 10% memory reduction. Moreover integrating with an advanced CUDA kernel achieves up to 60% speedup without extra memory costs or accuracy loss significantly enhancing the efficiency of fine-tuning foundation models on memory-constrained devices.
Action-slot: Visual Action-centric Representations for Multi-label Atomic Activity Recognition in Traffic Scenes
Authors: Shu-Wei Lu, Yi-Hsuan Tsai, Yi-Ting Chen Chi-Hsi Kung
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: In this paper we study multi-label atomic activity recognition. Despite the notable progress in action recognition it is still challenging to recognize atomic activities due to a deficiency in holistic understanding of both multiple road users' motions and their contextual information. In this paper we introduce Action-slot a slot attention-based approach that learns visual action-centric representations capturing both motion and contextual information. Our key idea is to design action slots that are capable of paying attention to regions where atomic activities occur without the need for explicit perception guidance. To further enhance slot attention we introduce a background slot that competes with action slots aiding the training process in avoiding unnecessary focus on background regions devoid of activities. Yet the imbalanced class distribution in the existing dataset hampers the assessment of rare activities. To address the limitation we collect a synthetic dataset called TACO which is four times larger than OATS and features a balanced distribution of atomic activities. To validate the effectiveness of our method we conduct comprehensive experiments and ablation studies against various action recognition baselines. We also show that the performance of multi-label atomic activity recognition on real-world datasets can be improved by pretraining representations on TACO.
Animatable Gaussians: Learning Pose-dependent Gaussian Maps for High-fidelity Human Avatar Modeling
Authors: Zerong Zheng, Lizhen Wang, Yebin Liu Zhe Li
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Modeling animatable human avatars from RGB videos is a long-standing and challenging problem. Recent works usually adopt MLP-based neural radiance fields (NeRF) to represent 3D humans but it remains difficult for pure MLPs to regress pose-dependent garment details. To this end we introduce Animatable Gaussians a new avatar representation that leverages powerful 2D CNNs and 3D Gaussian splatting to create high-fidelity avatars. To associate 3D Gaussians with the animatable avatar we learn a parametric template from the input videos and then parameterize the template on two front & back canonical Gaussian maps where each pixel represents a 3D Gaussian. The learned template is adaptive to the wearing garments for modeling looser clothes like dresses. Such template-guided 2D parameterization enables us to employ a powerful StyleGAN-based CNN to learn the pose-dependent Gaussian maps for modeling detailed dynamic appearances. Furthermore we introduce a pose projection strategy for better generalization given novel poses. Overall our method can create lifelike avatars with dynamic realistic and generalized appearances. Experiments show that our method outperforms other state-of-the-art approaches. Code: https://github.com/lizhe00/AnimatableGaussians.
Latency Correction for Event-guided Deblurring and Frame Interpolation
Authors: Jinxiu Liang, Bohan Yu, Yan Chen, Jimmy S. Ren, Boxin Shi Yixin Yang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Event cameras with their high temporal resolution dynamic range and low power consumption are particularly good at time-sensitive applications like deblurring and frame interpolation. However their performance is hindered by latency variability especially under low-light conditions and with fast-moving objects. This paper addresses the challenge of latency in event cameras -- the temporal discrepancy between the actual occurrence of changes in the corresponding timestamp assigned by the sensor. Focusing on event-guided deblurring and frame interpolation tasks we propose a latency correction method based on a parameterized latency model. To enable data-driven learning we develop an event-based temporal fidelity to describe the sharpness of latent images reconstructed from events and the corresponding blurry images and reformulate the event-based double integral model differentiable to latency. The proposed method is validated using synthetic and real-world datasets demonstrating the benefits of latency correction for deblurring and interpolation across different lighting conditions.
Retraining-Free Model Quantization via One-Shot Weight-Coupling Learning
Authors: Yuan Meng, Jiacheng Jiang, Shuzhao Xie, Rongwei Lu, Xinzhu Ma, Zhi Wang, Wenwu Zhu Chen Tang
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Quantization is of significance for compressing the over-parameterized deep neural models and deploying them on resource-limited devices. Fixed-precision quantization suffers from performance drop due to the limited numerical representation ability. Conversely mixed-precision quantization (MPQ) is advocated to compress the model effectively by allocating heterogeneous bit-width for layers. MPQ is typically organized into a searching-retraining two-stage process. Previous works only focus on determining the optimal bit-width configuration in the first stage efficiently while ignoring the considerable time costs in the second stage. However retraining always consumes hundreds of GPU-hours on the cutting-edge GPUs thus hindering deployment efficiency significantly. In this paper we devise a one-shot training-searching paradigm for mixed-precision model compression. Specifically in the first stage all potential bit-width configurations are coupled and thus optimized simultaneously within a set of shared weights. However our observations reveal a previously unseen and severe bit-width interference phenomenon among highly coupled weights during optimization leading to considerable performance degradation under a high compression ratio. To tackle this problem we first design a bit-width scheduler to dynamically freeze the most turbulent bit-width of layers during training to ensure the rest bit-widths converged properly. Then taking inspiration from information theory we present an information distortion mitigation technique to align the behaviour of the bad-performing bit-widths to the well-performing ones. In the second stage an inference-only greedy search scheme is devised to evaluate the goodness of configurations without introducing any additional training costs. Extensive experiments on three representative models and three datasets demonstrate the effectiveness of the proposed method.
EVCap: Retrieval-Augmented Image Captioning with External Visual-Name Memory for Open-World Comprehension
Authors: Duc Minh Vo, Akihiro Sugimoto, Hideki Nakayama Jiaxuan Li
Published in: IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2024 (Main Conference Track), 2024

Abstract: Large language models (LLMs)-based image captioning has the capability of describing objects not explicitly observed in training data; yet novel objects occur frequently necessitating the requirement of sustaining up-to-date object knowledge for open-world comprehension. Instead of relying on large amounts of data and/or scaling up network parameters we introduce a highly effective retrieval-augmented image captioning method that prompts LLMs with object names retrieved from External Visual--name memory (EVCap). We build ever-changing object knowledge memory using objects' visuals and names enabling us to (i) update the memory at a minimal cost and (ii) effortlessly augment LLMs with retrieved object names by utilizing a lightweight and fast-to-train model. Our model which was trained only on the COCO dataset can adapt to out-of-domain without requiring additional fine-tuning or re-training. Our experiments conducted on benchmarks and synthetic commonsense-violating data show that EVCap with only 3.97M trainable parameters exhibits superior performance compared to other methods based on frozen pre-trained LLMs. Its performance is also competitive to specialist SOTAs that require extensive training.