Video Individual Counting (VIC) is a recently introduced task that aims to estimate pedestrian flux from a video. It extends conventional Video Crowd Counting (VCC) beyond the per-frame pedestrian count. In contrast to VCC that only learns to count repeated pedestrian patterns across frames, the key problem of VIC is how to identify co-existent pedestrians between frames, which turns out to be a correspondence problem. Existing VIC approaches, however, mainly follow a one-to-one (O2O) matching strategy where the same pedestrian must be exactly matched between frames, leading to sensitivity to appearance variations or missing detections. In this work, we show that the O2O matching could be relaxed to a one-to-many (O2M) matching problem, which better fits the problem nature of VIC and can leverage the social grouping behavior of walking pedestrians. We therefore introduce OMAN, a simple but effective VIC model with implicit One-to-Many mAtchiNg, featuring an implicit context generator and a one-to-many pairwise matcher. Experiments on the SenseCrowd and CroHD benchmarks show that OMAN achieves the state-of-the-art performance. Code is available at \href{https://github.com/tiny-smart/OMAN}{OMAN}.
Traditional crowd counting approaches usually use Gaussian assumption to generate pseudo density ground truth, which suffers from problems like inaccurate estimation of the Gaussian kernel sizes. In this paper, we propose a new measure-based counting approach to regress the predicted density maps to the scattered point-annotated ground truth directly. First, crowd counting is formulated as a measure matching problem. Second, we derive a semi-balanced form of Sinkhorn divergence, based on which a Sinkhorn counting loss is designed for measure matching. Third, we propose a self-supervised mechan…
In crowd counting, each training image contains multiple people, where each person is annotated by a dot. Existing crowd counting methods need to use a Gaussian to smooth each annotated dot or to estimate the likelihood of every pixel given the annotated point. In this paper, we show that imposing Gaussians to annotations hurts generalization performance. Instead, we propose to use Distribution Matching for crowd COUNTing (DM-Count). In DM-Count, we use Optimal Transport (OT) to measure the similarity between the normalized predicted density map and the normalized ground truth density map. To …
Korea University（高丽大学）；UC Berkeley（加州大学伯克利分校）；Ewha Womans University（梨花女子大学）
Existing pipelines of semantic correspondence commonly include extracting high-level semantic features for the invariance against intra-class variations and background clutters. This architecture, however, inevitably results in a low-resolution matching field that additionally requires an ad-hoc interpolation process as a post-processing for converting it into a high-resolution one, certainly limiting the overall performance of matching results. To overcome this, inspired by recent success of implicit neural representation, we present a novel method for semantic correspondence, called Neural M…
Indian Institute of Science（印度科学理工学院）；Johns Hopkins University（约翰斯·霍普金斯大学）
Dense crowd counting is a challenging task that demands millions of head annotations for training models. Though existing self-supervised approaches could learn good representations, they require some labeled data to map these features to the end task of density estimation. We mitigate this issue with the proposed paradigm of complete self-supervision, which does not need even a single labeled image. The only input required to train, apart from a large set of unlabeled crowd images, is the approximate upper limit of the crowd count for the given dataset. Our method dwells on the idea that natu…
Hikvision Research Institute（海康威视研究院）；Zhejiang University（浙江大学）
Text recognition is a popular topic for its broad applications. In this work, we excavate the implicit task, character counting within the traditional text recognition, without additional labor annotation cost. The implicit task plays as an auxiliary branch for complementing the sequential recognition. We design a two-branch reciprocal feature learning framework in order to adequately utilize the features from both the tasks. Through exploiting the complementary effect between explicit and implicit tasks, the feature is reliably enhanced. Extensive experiments on 7 benchmarks show the advantag…
Huazhong University of Science and Technology（华中科技大学）
Class-agnostic counting (CAC) aims to count all instances in a query image given few exemplars. A standard pipeline is to extract visual features from exemplars and match them with query images to infer object counts. Two essential components in this pipeline are feature representation and similarity metric. Existing methods either adopt a pretrained network to represent features or learn a new one, while applying a naive similarity metric with fixed inner product. We find this paradigm leads to noisy similarity matching and hence harms counting performance. In this work, we propose a similari…
Establishing a correspondence between two non-rigidly deforming shapes is one of the most fundamental problems in visual computing. Existing methods often show weak resilience when presented with challenges innate to real-world data such as noise, outliers, self-occlusion etc. On the other hand, auto-decoders have demonstrated strong expressive power in learning geometrically meaningful latent embeddings. However, their use in \emph{shape analysis} has been limited. In this paper, we introduce an approach based on an auto-decoder framework, that learns a continuous shape-wise deformation field…
CogStereo: Neural Stereo Matching with Implicit Spatial Cognition Embedding
Robotics and Computer Vision (RCV) Laboratory, Southern University of Science and Technology (SUSTech)（机器人与计算机视觉实验室，南方科技大学）；International Digital Economy Academy (IDEA)（国际数字经济学院）；School of Automation Science and Engineering, Xi’an Jiaotong University (XJTU)（自动化科学与工程学院，西安交通大学）
Perceptual features (PFs) have been used with great success in tasks such as transfer learning, style transfer, and super-resolution. However, the efficacy of PFs as key source of information for learning generative models is not well studied. We investigate here the use of PFs in the context of learning implicit generative models through moment matching (MM). More specifically, we propose a new effective MM approach that learns implicit generative models by performing mean and covariance matching of features extracted from pretrained ConvNets. Our proposed approach improves upon existing MM m…
Match4Annotate: Cross-Video Annotation Transfer in Ultrasound via Implicit Feature Flow-Guided Matching
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, USA（麻省理工学院机械工程系）；Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, USA（麻省理工学院医学工程与科学研究所）；MIT.nano Immersion Lab, Massachusetts Institute of Technology, Cambridge, USA（麻省理工学院MIT.nano沉浸实验室）
University of Jena（耶拿大学）；UC Berkeley（加州大学伯克利分校）；Carl Zeiss AG（卡尔蔡司股份公司）
Most recent CNN architectures use average pooling as a final feature encoding step. In the field of fine-grained recognition, however, recent global representations like bilinear pooling offer improved performance. In this paper, we generalize average and bilinear pooling to "alpha-pooling", allowing for learning the pooling strategy during training. In addition, we present a novel way to visualize decisions made by these approaches. We identify parts of training images having the highest influence on the prediction of a given test image. It allows for justifying decisions to users and also fo…
Nearly all existing counting methods are designed for a specific object class. Our work, however, aims to create a counting model able to count any class of object. To achieve this goal, we formulate counting as a matching problem, enabling us to exploit the image self-similarity property that naturally exists in object counting problems. We make the following three contributions: first, a Generic Matching Network (GMN) architecture that can potentially count any object in a class-agnostic manner; second, by reformulating the counting problem as one of matching objects, we can take advantage o…
Sparis: Neural Implicit Surface Reconstruction of Indoor Scenes from Sparse Views
Beijing National Research Center for Information Science and Technology (BNRist), Tsinghua University（北京信息科学与技术国家研究中心（BNRist），清华大学）；School of Software, Tsinghua University（清华大学软件学院）
Anchor Token Matching: Implicit Structure Locking for Training-free AR Image Editing
VCIP, College of Computer Science, Nankai University（VCIP，计算机科学学院，南开大学）；NKIARI, Shenzhen Futian（NKIARI，深圳福田）；Computer Vision Center, Universitat Autònoma de Barcelona（计算机视觉中心，巴塞罗那自治大学）；City University of Hong Kong (Dongguan)（香港城市大学（东莞））
Real-World Blind Super-Resolution via Feature Matching with Implicit High-Resolution Priors
School of Informatics, Xiamen University（厦门大学信息学院）；School of Computer Science（计算机科学学院）；Faculty of Computing, Harbin Institute of Technology（哈尔滨工业大学计算机学院）；DAMO Academy, Alibaba Group（阿里巴巴集团达摩院）；SSE, The Chinese University of Hong Kong（香港中文大学（深圳）SSE）
ViBA: Implicit Bundle Adjustment with Geometric and Temporal Consistency for Robust Visual Matching
GNSS Research Center, Wuhan University（武汉大学卫星导航定位技术研究中心）；Electronic Information School, Wuhan University（武汉大学电子信息学院）；Hubei Technology Innovation Center for Spatiotemporal Information and Positioning Navigation（湖北省时空信息与定位导航技术创新中心）；Hubei Luojia Laboratory（湖北珞珈实验室）
Counting Trees from Satellite Imagery with Noisy Supervision
University of Copenhagen（哥本哈根大学）；University of Rwanda（卢旺达大学）；University of Chinese Academy of Sciences（中国科学院大学）；University of North Carolina at Charlotte（北卡罗来纳大学夏洛特分校）；Stony Brook University（石溪大学）；LIGM, CNRS, Univ Gustave Eiffel, ENPC, IPP（LIGM，CNRS，古斯塔夫·埃菲尔大学，ENPC，IPP）
Sun Yat-sen University（中山大学）；University of Technology Sydney（悉尼科技大学）；Guangdong University of Foreign Studies（广东外语外贸大学）；Guilin University of Electronic Technology（桂林电子科技大学）
In this paper, we aim at tackling the problem of crowd counting in extremely high-density scenes, which contain hundreds, or even thousands of people. We begin by a comprehensive analysis of the most widely used density map-based methods, and demonstrate how easily existing methods are affected by the inhomogeneous density distribution problem, e.g., causing them to be sensitive to outliers, or be hard to optimized. We then present an extremely simple solution to the inhomogeneous density distribution problem, which can be intuitively summarized as extending the density map from 2D to 3D, with…
An intuitive way to search for images is to use queries composed of an example image and a complementary text. While the first provides rich and implicit context for the search, the latter explicitly calls for new traits, or specifies how some elements of the example image should be changed to retrieve the desired target image. Current approaches typically combine the features of each of the two elements of the query into a single representation, which can then be compared to the ones of the potential target images. Our work aims at shedding new light on the task by looking at it through the p…
