Existing techniques to compress point cloud attributes leverage either geometric or video-based compression tools. We explore a radically different approach inspired by recent advances in point cloud representation learning. Point clouds can be interpreted as 2D manifolds in 3D space. Specifically, we fold a 2D grid onto a point cloud and we map attributes from the point cloud onto the folded 2D grid using a novel optimized mapping method. This mapping results in an image, which opens a way to apply existing image processing techniques on point cloud attributes. However, as this mapping process is lossy in nature, we propose several strategies to refine it so that attributes can be mapped to the 2D grid with minimal distortion. Moreover, this approach can be flexibly applied to point cloud patches in order to better adapt to local geometric complexity. In this work, we consider point cloud attribute compression; thus, we compress this image with a conventional 2D image codec. Our preliminary results show that the proposed folding-based coding scheme can already reach performance similar to the latest MPEG Geometry-based PCC (G-PCC) codec.
Sun Yat-sen University（中山大学）；The Shenzhen Campus of Sun Yat-sen University（中山大学深圳校区）；University of Oxford（牛津大学）；Information Engineering University（信息工程大学）；Shanghai Jiaotong University（上海交通大学）；National University of Defense Technology（国防科技大学）
We study the problem of attribute compression for large-scale unstructured 3D point clouds. Through an in-depth exploration of the relationships between different encoding steps and different attribute channels, we introduce a deep compression network, termed 3DAC, to explicitly compress the attributes of 3D point clouds and reduce storage usage in this paper. Specifically, the point cloud attributes such as color and reflectance are firstly converted to transform coefficients. We then propose a deep entropy model to model the probabilities of these coefficients by considering information hidd…
In point cloud compression, exploiting temporal redundancy for inter predictive coding is challenging because of the irregular geometry. This paper proposes an efficient block-based inter-coding scheme for color attribute compression. The scheme includes integer-precision motion estimation and an adaptive graph based in-loop filtering scheme for improved attribute prediction. The proposed block-based motion estimation scheme consists of an initial motion search that exploits geometric and color attributes, followed by a motion refinement that only minimizes color prediction error. To further i…
Att2CPC: Attention-Guided Lossy Attribute Compression of Point Clouds
College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics（南京航空航天大学计算机科学与技术学院）；School of Computing and Mathematics, Charles Sturt University（查尔斯斯特大学计算与数学学院）
Sun Yat-sen University（中山大学）；University of Oxford（牛津大学）；Shanghai Jiaotong University（上海交通大学）
With the development of the 3D data acquisition facilities, the increasing scale of acquired 3D point clouds poses a challenge to the existing data compression techniques. Although promising performance has been achieved in static point cloud compression, it remains under-explored and challenging to leverage temporal correlations within a point cloud sequence for effective dynamic point cloud compression. In this paper, we study the attribute (e.g., color) compression of dynamic point clouds and present a learning-based framework, termed 4DAC. To reduce temporal redundancy within data, we firs…
Peng Cheng Lab（鹏程实验室）；Peking University, Shenzhen Graduate School（北京大学深圳研究生院）；University of Southern California（南加州大学）
Inspired by the recently proposed successive subspace learning (SSL) principles, we develop a successive subspace graph transform (SSGT) to address point cloud attribute compression in this work. The octree geometry structure is utilized to partition the point cloud, where every node of the octree represents a point cloud subspace with a certain spatial size. We design a weighted graph with self-loop to describe the subspace and define a graph Fourier transform based on the normalized graph Laplacian. The transforms are applied to large point clouds from the leaf nodes to the root node of the …
University of Science and Technology of China（中国科学技术大学）
Geometry-based point cloud compression (G-PCC) can achieve remarkable compression efficiency for point clouds. However, it still leads to serious attribute compression artifacts, especially under low bitrate scenarios. In this paper, we propose a Multi-Scale Graph Attention Network (MS-GAT) to remove the artifacts of point cloud attributes compressed by G-PCC. We first construct a graph based on point cloud geometry coordinates and then use the Chebyshev graph convolutions to extract features of point cloud attributes. Considering that one point may be correlated with points both near and far …
Hangzhou Normal University（杭州师范大学）；Nanjing University（南京大学）
A learning-based adaptive loop filter is developed for the Geometry-based Point Cloud Compression (G-PCC) standard to reduce attribute compression artifacts. The proposed method first generates multiple Most-Probable Sample Offsets (MPSOs) as potential compression distortion approximations, and then linearly weights them for artifact mitigation. As such, we drive the filtered reconstruction as close to the uncompressed PCA as possible. To this end, we devise a Compression Artifact Reduction Network (CARNet) which consists of two consecutive processing phases: MPSOs derivation and MPSOs combina…
DALD-PCAC: Density-Adaptive Learning Descriptor for Point Cloud Lossless Attribute Compression
City University of Hong Kong（香港城市大学）；Peking University Shenzhen Graduate School（北京大学深圳研究生院）；University of Missouri-Kansas City（密苏里大学-堪萨斯城分校）；Tencent Media Laboratory（腾讯媒体实验室）
Packet-Loss Robust 3D Gaussian Compression via Atomic Packaging and GNN-based Error Concealment
Central South University Changsha China；Malanshan Audio \& Video Laboratory Changsha China；Central South University；Malanshan Audio \& Video Laboratory
Deep-JGAC: End-to-End Deep Joint Geometry and Attribute Compression for Dense Colored Point Clouds
School of Electronics and Communication Engineering, Shenzhen Campus, Sun Yat-Sen University（中山大学深圳校区电子与通信工程学院）；Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences（中国科学院深圳先进技术研究院）；Department of Electrical and Computer Engineering, University of Southern California（南加州大学电子与计算机工程系）
College of Information Science and Electronic Engineering, Zhejiang University（浙江大学信息科学与电子工程学院）；Department of Electrical and Electronic Engineering, The University of Hong Kong（香港大学电子与电气工程系）；College of Computing and Data Science, Nanyang Technological University（南洋理工大学计算机与数据科学学院）
MesonGS: Post-training Compression of 3D Gaussians via Efficient Attribute Transformation
MMLab, The Chinese University of Hong Kong（香港中文大学MMLab实验室）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；SIGS & TBSI, Tsinghua University（清华大学深圳国际研究生院与清华-伯克利深圳学院）；Peng Cheng Laboratory（鹏城实验室）
Efficient and Generic Point Model for Lossless Point Cloud Attribute Compression
College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics（南京航空航天大学计算机科学与技术学院）；School of Electronic Science and Engineering, Nanjing University（南京大学电子科学与工程学院）
Nanjing University（南京大学）；Hangzhou Normal University（杭州师范大学）；University of Missouri（密苏里大学）
Recent years have witnessed the growth of point cloud based applications because of its realistic and fine-grained representation of 3D objects and scenes. However, it is a challenging problem to compress sparse, unstructured, and high-precision 3D points for efficient communication. In this paper, leveraging the sparsity nature of point cloud, we propose a multiscale end-to-end learning framework which hierarchically reconstructs the 3D Point Cloud Geometry (PCG) via progressive re-sampling. The framework is developed on top of a sparse convolution based autoencoder for point cloud compressio…
SPAC: Sampling-based Progressive Attribute Compression for Dense Point Clouds
School of Control Science and Engineering, Shandong University（山东大学控制科学与工程学院）；School of Engineering and Sustainable Development, De Montfort University（德蒙福特大学工程与可持续发展学院）；School of Data Science, Lingnan University（岭南大学数据科学学院）
Rendering-Oriented 3D Point Cloud Attribute Compression using Sparse Tensor-based Transformer
School of Telecommunication Engineering, Xidian University（西安电子科技大学通信工程学院）；City University of Hong Kong（香港城市大学）；School of Electronics and Information, Northwestern Polytechnical University（西北工业大学电子信息学院）；School of Engineering, Royal Melbourne Institute of Technology（皇家墨尔本理工大学工程学院）
A Benchmark for Gaussian Splatting Compression and Quality Assessment Study
School of Science and Engineering, University of Missouri - Kansas City（密苏里大学堪萨斯城分校科学与工程学院）；Cooperative Medianet Innovation Center, Shanghai Jiaotong University（上海交通大学合作 medianet 创新中心）
Ecole Polytechnique Fédérale de Lausanne (EPFL)（洛桑联邦理工学院）；Microsoft Research（微软研究院）
This paper addresses the problem of compression of 3D point cloud sequences that are characterized by moving 3D positions and color attributes. As temporally successive point cloud frames are similar, motion estimation is key to effective compression of these sequences. It however remains a challenging problem as the point cloud frames have varying numbers of points without explicit correspondence information. We represent the time-varying geometry of these sequences with a set of graphs, and consider 3D positions and color attributes of the points clouds as signals on the vertices of the grap…
University of Southern California（南加州大学）；KDDI Research Inc（KDDI研究所）
Motivated by the success of fractional pixel motion in video coding, we explore the design of motion estimation with fractional-voxel resolution for compression of color attributes of dynamic 3D point clouds. Our proposed block-based fractional-voxel motion estimation scheme takes into account the fundamental differences between point clouds and videos, i.e., the irregularity of the distribution of voxels within a frame and across frames. We show that motion compensation can benefit from the higher resolution reference and more accurate displacements provided by fractional precision. Our propo…
Local density of point clouds is crucial for representing local details, but has been overlooked by existing point cloud compression methods. To address this, we propose a novel deep point cloud compression method that preserves local density information. Our method works in an auto-encoder fashion: the encoder downsamples the points and learns point-wise features, while the decoder upsamples the points using these features. Specifically, we propose to encode local geometry and density with three embeddings: density embedding, local position embedding and ancestor embedding. During the decodin…
UGAE: Unified Geometry and Attribute Enhancement for G-PCC Compressed Point Clouds
School of Control Science and Engineering, Shandong University（控制科学与工程学院，山东大学）；Key Laboratory of Machine Intelligence and System Control, Ministry of Education（机器智能与系统控制重点实验室，教育部）；School of Engineering and Sustainable Development, De Montfort University（工程与可持续发展学院，德蒙福特大学）；Institute of NUIST-MetaX for Graphics Processing Unit, Nanjing University of Information Science and Technology（信息科学技术大学NUIST-MetaX图形处理单元研究所）
Point Cloud Compression and Objective Quality Assessment: A Survey
Cooperative Medianet Innovation Center, Shanghai Jiao Tong University（上海交通大学合作中位网创新中心）；University of Missouri–Kansas City（密苏里大学-堪萨斯城分校）；Department of Electrical and Computer Engineering, University of Canterbury（坎特伯雷大学电子与计算机工程系）
University Paris-Est（巴黎东大学）；ESIEE Paris（巴黎高等电子工程师学院）；INRIA（法国国家信息与自动化研究所）；ENS（巴黎高等师范学院）；PSL Research University（巴黎文理研究大学）；HoloMake；IFP Energies nouvelles（法国新能源与原子能委员会石油与新能源研究所）；Université Côte d’Azur（蔚蓝海岸大学）；CNRS（法国国家科学研究中心）
With huge data acquisition progresses realized in the past decades and acquisition systems now able to produce high resolution grids and point clouds, the digitization of physical terrains becomes increasingly more precise. Such extreme quantities of generated and modeled data greatly impact computational performances on many levels of high-performance computing (HPC): storage media, memory requirements, transfer capability, and finally simulation interactivity, necessary to exploit this instance of big data. Efficient representations and storage are thus becoming "enabling technologies'' in H…
Efficient LiDAR Reflectance Compression via Scanning Serialization
School of Information Science and Technology, Hangzhou Normal University, Hangzhou, China（信息科学与技术学院，杭州师范大学）；School of Electronic Science and Engineering, Nanjing University, Nanjing, China（电子科学与工程学院，南京大学）
