An Efficient LiDAR Point Cloud Map Coding Scheme Based on Segmentation and Frame-Inserting Network

• Published in: Sensors (Basel, Switzerland) Vol. 22; no. 14; p. 5108
• Main Authors: Wang, Qiang, Jiang, Liuyang, Sun, Xuebin, Zhao, Jingbo, Deng, Zhaopeng, Yang, Shizhong
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 07.07.2022; MDPI
• Subjects: Algorithms; Autonomous vehicles; coding; Coding standards; Computer architecture; Frames; Geometry; Interpolation; LiDAR; Localization; Mapping; Methods; Octrees; point cloud map; Quaternions; Registration; Robots; segmentation
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s22145108

In this article, we present an efficient coding scheme for LiDAR point cloud maps. As a point cloud map consists of numerous single scans spliced together, by recording the time stamp and quaternion matrix of each scan during map building, we cast the point cloud map compression into the point cloud sequence compression problem. The coding architecture includes two techniques: intra-coding and inter-coding. For intra-frames, a segmentation-based intra-prediction technique is developed. For inter-frames, an interpolation-based inter-frame coding network is explored to remove temporal redundancy by generating virtual point clouds based on the decoded frames. We only need to code the difference between the original LiDAR data and the intra/inter-predicted point cloud data. The point cloud map can be reconstructed according to the decoded point cloud sequence and quaternion matrices. Experiments on the KITTI dataset show that the proposed coding scheme can largely eliminate the temporal and spatial redundancies. The point cloud map can be encoded to 1/24 of its original size with 2 mm-level precision. Our algorithm also obtains better coding performance compared with the octree and Google Draco algorithms.