pwc-archive/papers-with-abstracts huggingface dataset:
ReGen: A good Generative Zero-Shot Video Classifier Should be Rewarded
Authors: Adrian Bulat, Enrique Sanchez, Brais Martinez, Georgios Tzimiropoulos
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Action Classification, Action Recognition, Descriptive, reinforcement-learning, Temporal Action Localization, Video Captioning

    This paper sets out to solve the following problem: How can we turn a generative video captioning model into an open-world video/action classification model? Video captioning models can naturally produce open-ended free-form descriptions of a given video which, however, might not be discriminative enough for video/action recognition. Unfortunately, when fine-tuned to auto-regress the class names directly, video captioning models overfit the base classes losing their open-world zero-shot capabilities. To alleviate base class overfitting, in this work, we propose to use reinforcement learning to enforce the output of the video captioning model to be more class-level discriminative. Specifically, we propose ReGen, a novel reinforcement learning based framework with a three-fold objective and reward functions: (1) a class-level discrimination reward that enforces the generated caption to be correctly classified into the corresponding action class, (2) a CLIP reward that encourages the generated caption to continue to be descriptive of the input video (i.e. video-specific), and (3) a grammar reward that preserves the grammatical correctness of the caption. We show that ReGen can train a model to produce captions that are: discriminative, video-specific and grammatically correct. Importantly, when evaluated on standard benchmarks for zero- and few-shot action classification, ReGen significantly outperforms the previous state-of-the-art.
Tracking by Natural Language Specification with Long Short-term Context Decoupling
Authors: Ding Ma, Xiangqian Wu
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1

    The main challenge of Tracking by Natural Language Specification (TNL) is to predict the movement of the target object by giving two heterogeneous information, e.g., one is the static description of the main characteristics of a video contained in the textual query, i.e., long-term context; the other one is an image patch containing the object and its surroundings cropped from the current frame, i.e., the search area. Currently, most methods still struggle with the rationality of using those two information and simply fusing the two. However, the linguistic information contained in the textual query and the visual representation stored in the search area may sometimes be inconsistent, in which case the direct fusion of the two may lead to conflicts. To address this problem, we propose DecoupleTNL, introducing a video clip containing short-term context information into the framework of TNL and exploring a proper way to reduce the impact when visual representation is inconsistent with linguistic information. Concretely, we design two jointly optimized tasks, i.e., short-term context-matching and long-term context-perceiving. The context-matching task aims to gather the dynamic short-term context information in a period, while the context-perceiving task tends to extract the static long-term context information. After that, we design a long short-term modulation module to integrate both context information for accurate tracking. Extensive experiments have been conducted on three tracking benchmark datasets to demonstrate the superiority of DecoupleTNL
High Quality Entity Segmentation
Authors: Lu Qi, Jason Kuen, Tiancheng Shen, Jiuxiang Gu, Wenbo Li, Weidong Guo, Jiaya Jia, Zhe Lin, Ming-Hsuan Yang
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Image Segmentation, Panop, Segmentation, Semantic Segmentation

    Dense image segmentation tasks (e.g., semantic, panop tic) are useful for image editing, but existing methods can hardly generalize well in an in-the-wild setting where there are unrestricted image domains, classes, and image reso lution & quality variations. Motivated by these observa tions, we construct a new entity segmentation dataset, with a strong focus on high-quality dense segmentation in the wild. The dataset contains images spanning diverse image domains and entities, along with plent(ful high-resolution images and high-quality mask annotations for training and testing. Given the high-quality and -resolution nature of the dataset, we propose CropFormer which is designed to tackle the intractability of instance-level segmentation on high-resolution images. It improves mask prediction by fusing high-res image crops that provides more fine grained image details and the full image. CropFormer is the first query-based Tran. former architecture that can ef fectively fuse mask predictions from multiple image views, by learning queries that effectively associate the same en tities across the full image and its crop. With CropFormer, we achieve a significant AP gain of 1.9 on the challenging entity segmentation task. Furthermore, CropFormer con sistently improves the accuracy of traditional segmentation tasks and datasets. The dataset and code are released at http://luqi.info/entityv2.github.iol
Towards Understanding the Generalization of Deepfake Detectors from a Game-Theoretical View
Authors: Kelu Yao, Jin Wang, Boyu Diao, Chao Li
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: DeepFake Detection, Face Swapping

    This paper aims to explain the generalization of deepfake detectors from the novel perspective of multi-order interactions among visual concepts. Specifically, we propose three hypotheses:  1. Deepfake detectors encode multi-order interactions among visual concepts, in which the low-order interactions usually have substantially negative contributions to deepfake detection.  2. Deepfake detectors with better generalization abilities tend to encode low-order interactions with fewer negative contributions.  3. Generalized deepfake detectors usually weaken the negative contributions of low-order interactions by suppressing their strength. Accordingly, we design several mathematical metrics to evaluate the effect of low-order interaction for deepfake detectors. Extensive comparative experiments are conducted, which verify the soundness of our hypotheses. Based on the analyses, we further propose a generic method, which directly reduces the toxic effects of low-order interactions to improve the generalization of deepfake detectors to some extent.  The code will be released when the paper is accepted.
Continual Learning for Personalized Co-speech Gesture Generation
Authors: Chaitanya Ahuja, Pratik Joshi, Ryo Ishii, Louis-Philippe Morency
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Continual Learning, Gesture Generation

    Co-speech gestures are a key channel of human communication, making them important for personalized chat agents to generate. In the past, gesture generation models assumed that data for each speaker is available all at once, and in large amounts. However in practical scenarios, speaker data comes sequentially and in small amounts as the agent personalizes with more speakers, akin to a continual learning paradigm. While more recent works have shown progress in adapting to low-resource data, they catastrophically forget the gesture styles of initial speakers they were trained on. Also, prior generative continual learning works are not multimodal, making this space less studied. In this paper, we explore this new paradigm and propose C-DiffGAN: an approach that continually learns new speaker gesture styles with only a few minutes of per-speaker data, while retaining previously learnt styles. Inspired by prior continual learning works, C-DiffGAN encourages knowledge retention by 1) generating reminiscences of previous low-resource speaker data, then 2) crossmodally aligning to them to mitigate catastrophic forgetting. We quantitatively demonstrate improved performance and reduced forgetting over strong baselines through standard continual learning measures, reinforced by a qualitative user study that shows that our method produces more natural, style-preserving gestures. Code and videos can be found at https://chahuja.com/cdiffgan
DG3D: Generating High Quality 3D Textured Shapes by Learning to Discriminate Multi-Modal Diffusion-Renderings
Authors: Qi Zuo, Yafei Song, Jianfang Li, Lin Liu, Liefeng Bo
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1

    Many virtual reality applications require massive 3D content, which impels the need for low-cost and efficient modeling tools in terms of quality and quantity. In this paper, we present a Diffusion-augmented Generative model to generate high-fidelity 3D textured meshes that can be directly used in modern graphics engines. Challenges in directly generating textured mesh arise from the instability and texture incompleteness of a hybrid framework which contains conversion between 2D features and 3D space. To alleviate these difficulties, DG3D incorporates a diffusion-based augmentation module into the min-max game between the 3D tetrahedral mesh generator and 2D renderings discriminators, which stabilizes network optimization and prevents mode collapse in vanilla GANs. We also suggest using multi-modal renderings in discrimination to further increase the aesthetics and completeness of generated textures. Extensive experiments on the public benchmark and real scans show that our proposed DG3D outperforms existing state-of-the-art methods by a large margin, i.e., 5%   40% in FID-3D score and 5%   10% in geometry-related metrics. Code is available at https://github.com/seakforzq/DG3D.
Essential Matrix Estimation using Convex Relaxations in Orthogonal Space
Authors: Arman Karimian, Roberto Tron
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1

    We introduce a novel method to estimate the essential matrix for two-view Structure from Motion (SfM). We show that every 3 by 3 essential matrix can be embedded in a 4 by 4 rotation, having its bottom right entry fixed to zero; we call the latter the quintessential matrix. This embedding leads to rich relations with the space of 4-D rotations, quaternions, and the classical twisted-pair ambiguity in two-view SfM. We use this structure to derive a succession of semidefinite relaxations that require fewer parameters than the existing non-minimal solvers and yield faster convergence with certifiable optimality. We then exploit the low-rank geometry of these relaxations to reduce them to an equivalent optimization on a Riemannian manifold and solve them via the Riemannian Staircase method. The experimental evaluation confirms that our algorithm always finds the globally optimal solution and outperforms the existing non-minimal methods. We make our implementations open source.
CrossMatch: Source-Free Domain Adaptive Semantic Segmentation via Cross-Modal Consistency Training
Authors: Yifang Yin, Wenmiao Hu, Zhenguang Liu, Guanfeng Wang, Shili Xiang, Roger Zimmermann
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Denoising, Domain Adaptation, Pseudo Label, Semantic Segmentation, Unsupervised Domain Adaptation

    Source-free domain adaptive semantic segmentation has gained increasing attention recently. It eases the requirement of full data access to the source domain by transferring knowledge only from a well-trained source model. However, reducing the uncertainty of the target pseudo labels becomes inevitably more challenging without the supervision of the labeled source data. In this work, we propose a novel asymmetric two-stream architecture that learns more robustly from noisy pseudo labels. Our approach simultaneously conducts dual-head pseudo label denoising and cross-modal consistency regularization. Towards the former, we introduce a multimodal auxiliary network during training (and discard it during inference), which effectively enhances the pseudo labels' correctness by leveraging the guidance from the depth information. Towards the latter, we enforce a new cross-modal pixel-wise consistency between the predictions of the two streams, encouraging our model to behave smoothly for both modality variance and image perturbations. It serves as an effective regularization to further reduce the impact of the inaccurate pseudo labels in source-free unsupervised domain adaptation. Experiments on GTA5 to Cityscapes and SYNTHIA to Cityscapes benchmarks demonstrate the superiority of our proposed method, obtaining the new state-of-the-art mIoU of 57.7% and 57.5%, respectively.
Re:PolyWorld - A Graph Neural Network for Polygonal Scene Parsing
Authors: Stefano Zorzi, Friedrich Fraundorfer
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Graph Neural Network, Instance Segmentation, Scene Parsing, Semantic Segmentation, Wireframe Parsing

    While most state-of-the-art instance segmentation methods produce pixel-wise segmentation masks, numerous applications demand precise vector polygons of detected objects instead of rasterized output. This paper proposes Re:PolyWorld as a remastered and improved version of PolyWorld, a neural network that extracts object vertices from an image and connects them optimally to generate precise polygons. The objective of this work was to overcome weaknesses and shortcomings of the original model, as well as introducing an improved polygonal representation to obtain a general-purpose method for polygon extraction in images. The architecture has been redesigned to not only exploit vertex features, but to also make use of the visual appearance of edges. To this end, an edge-aware Graph Neural Network predicts the connection strength between each pair of vertices, which is further used to compute the assignment by solving a differentiable optimal transport problem. The proposed redefinition of the polygonal scene turns the method into a powerful generalized approach that can be applied to a large variety of tasks and problem settings, such as building extraction, floorplan reconstruction and even wireframe parsing. Re:PolyWorld not only outperforms the original model on building extraction in aerial images, thanks to the proposed joint analysis of vertices and edges, but also beats the state-of-the-art in multiple other domains.
Rethinking Point Cloud Registration as Masking and Reconstruction
Authors: Guangyan Chen, Meiling Wang, Li Yuan, Yi Yang, Yufeng Yue
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Point Cloud Registration

    Point cloud registration is essential in computer vision and robotics. In this paper, a critical observation is made that the invisible parts of each point cloud can be directly utilized as inherent masks, and the aligned point cloud pair can be regarded as the reconstruction target. Motivated by this observation, we rethink the point cloud registration problem as a masking and reconstruction task. To this end, a generic and concise auxiliary training network, the Masked Reconstruction Auxiliary Network (MRA), is proposed. The MRA reconstructs the complete point cloud by separately using the encoded features of each point cloud obtained from the backbone, guiding the contextual features in the backbone to capture fine-grained geometric details and the overall structures of point cloud pairs. Unlike recently developed high-performing methods that incorporate specific encoding methods into transformer models, which sacrifice versatility and introduce significant computational complexity during the inference process, our MRA can be easily inserted into other methods to further improve registration accuracy. Additionally, the MRA is detached after training, thereby avoiding extra computational complexity during the inference process. Building upon the MRA, we present a novel transformer-based method, the Masked Reconstruction Transformer (MRT), which achieves both precise and efficient alignment using standard transformers. Extensive experiments conducted on the 3DMatch, ModelNet40, and KITTI datasets demonstrate the superior performance of our MRT over state-of-the-art methods, and the efficiency of the MRA in improving registration accuracy.
BT^2: Backward-compatible Training with Basis Transformation
Authors: Yifei Zhou, Zilu Li, Abhinav Shrivastava, Hengshuang Zhao, Antonio Torralba, Taipeng Tian, Ser-Nam Lim
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1

    Modern retrieval system often requires recomputing the representation of every piece of data in the gallery when updating to a better representation model. This process is known as backfilling and can be especially costly in the real world where the gallery often contains billions of samples. Recently, researchers have proposed the idea of Backward Compatible Training (BCT) where the new representation model can be trained with an auxiliary loss to make it backward compatible with the old representation. In this way, the new representation can be directly compared with the old representation, in principle avoiding the need for any backfilling. However, follow-up work shows that there is an inherent trade-off where a backward-compatible representation model cannot simultaneously maintain the performance of the new model itself. This paper reports our "not-so-surprising" finding that adding extra dimensions to the representation can help here. However, we also found that naively increasing the dimension of the representation did not work. To deal with this, we propose Backward-compatible Training with a novel Basis Transformation (BT2). A basis transformation (BT) is basically a learnable set of parameters that applies an orthonormal transformation. Such a transformation possesses an important property whereby the original information contained in its input is retained in its output. We show in this paper how a BT can be utilized to add only the necessary amount of additional dimensions. We empirically verify the advantage of BT2 over other state-of-the-art methods in a wide range of settings. We then further extend BT2 to other challenging yet more practical settings, including significant changes in model architecture (CNN to Transformers), modality change, and even a series of updates in the model architecture mimicking the evolution of deep learning models in the past decade.
MAP: Towards Balanced Generalization of IID and OOD through Model-Agnostic Adapters
Authors: Min Zhang, Junkun Yuan, Yue He, Wenbin Li, Zhengyu Chen, Kun Kuang
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Bilevel Optimization, Inductive Bias

    Deep learning has achieved tremendous success in recent years, but most of these successes are built on an independent and identically distributed (IID) assumption. This somewhat hinders the application of deep learning to the more challenging out-of-distribution (OOD) scenarios. Although many OOD methods have been proposed to address this problem and have obtained good performance on testing data that is of major shifts with training distributions, interestingly, we experimentally find that these methods achieve excellent OOD performance by making a great sacrifice of the IID performance. We call this finding the IID-OOD dilemma. Clearly, in real-world applications, distribution shifts between training and testing data are often uncertain, where shifts could be minor, and even close to the IID scenario, and thus it is truly important to design a deep model with the balanced generalization ability between IID and OOD. To this end, in this paper, we investigate an intriguing problem of balancing IID and OOD generalizations and propose a novel Model Agnostic adaPters (MAP) method, which is more reliable and effective for distribution-shift-agnostic real-world data. Our key technical contribution is to use auxiliary adapter layers to incorporate the inductive bias of IID into OOD methods. To achieve this goal, we apply a bilevel optimization to explicitly model and optimize the coupling relationship between the OOD model and auxiliary adapter layers. We also theoretically give a first-order approximation to save computational time. Experimental results on six datasets successfully demonstrate that MAP can greatly improve the performance of IID while achieving good OOD performance.
PODA: Prompt-driven Zero-shot Domain Adaptation
Authors: Mohammad Fahes, Tuan-Hung Vu, Andrei Bursuc, Patrick Pérez, Raoul de Charette
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: Domain Adaptation, image-classification, Image Classification, Language Modeling, Language Modelling, object-detection, Object Detection, One-shot Unsupervised Domain Adaptation, Prompt-driven Zero-shot Domain Adaptation, Semantic Segmentation, Style Transfer, Unsupervised Domain Adaptation

    Domain adaptation has been vastly investigated in computer vision but still requires access to target images at train time, which might be intractable in some uncommon conditions. In this paper, we propose the task of 'Prompt-driven Zero-shot Domain Adaptation', where we adapt a model trained on a source domain using only a general description in natural language of the target domain, i.e., a prompt. First, we leverage a pretrained contrastive vision-language model (CLIP) to optimize affine transformations of source features, steering them towards the target text embedding while preserving their content and semantics. To achieve this, we propose Prompt-driven Instance Normalization (PIN). Second, we show that these prompt-driven augmentations can be used to perform zero-shot domain adaptation for semantic segmentation. Experiments demonstrate that our method significantly outperforms CLIP-based style transfer baselines on several datasets for the downstream task at hand, even surpassing one-shot unsupervised domain adaptation. A similar boost is observed on object detection and image classification. The code is available at https://github.com/astra-vision/PODA .
UHDNeRF: Ultra-High-Definition Neural Radiance Fields
Authors: Quewei Li, Feichao Li, Jie Guo, Yanwen Guo
Date: 2023-01-01 00:00:00
Proceeding: ICCV 2023 1
Tasks: 4k, NeRF, Novel View Synthesis

    We propose UHDNeRF, a new framework for novel view synthesis on the challenging ultra-high-resolution (e.g., 4K) real-world scenes. Previous NeRF methods are not specifically designed for rendering on extremely high resolutions, leading to burry results with notable detail-losing problems even though trained on 4K images. This is mainly due to the mismatch between the high-resolution inputs and the low-dimensional volumetric representation. To address this issue, we introduce an adaptive implicit-explicit scene representation with which an explicit sparse point cloud is used to boost the performance of an implicit volume on modeling subtle details. Specifically, we reconstruct the complex real-world scene with a frequency separation strategy that the implicit volume learns to represent the low-frequency properties of the whole scene, and the sparse point cloud is used for reproducing high-frequency details. To better explore the information embedded in the point cloud, we extract a global structure feature and a local point-wise feature from the point cloud for each sample located in the high-frequency regions. Furthermore, a patch-based sampling strategy is introduced to reduce the computational cost. The high-fidelity rendering results demonstrate the superiority of our method for retaining high-frequency details at 4K ultra-high-resolution scenarios against state-of-the-art NeRF-based solutions.