Lidar Panoptic Segmentation in an Open World

Bibliographic Details
Title: Lidar Panoptic Segmentation in an Open World
Authors: Chakravarthy, Anirudh S, Ganesina, Meghana Reddy, Hu, Peiyun, Leal-Taixe, Laura, Kong, Shu, Ramanan, Deva, Osep, Aljosa
Publication Year: 2024
Collection: Computer Science
Subject Terms: Computer Science - Computer Vision and Pattern Recognition
More Details: Addressing Lidar Panoptic Segmentation (LPS ) is crucial for safe deployment of autonomous vehicles. LPS aims to recognize and segment lidar points w.r.t. a pre-defined vocabulary of semantic classes, including thing classes of countable objects (e.g., pedestrians and vehicles) and stuff classes of amorphous regions (e.g., vegetation and road). Importantly, LPS requires segmenting individual thing instances (e.g., every single vehicle). Current LPS methods make an unrealistic assumption that the semantic class vocabulary is fixed in the real open world, but in fact, class ontologies usually evolve over time as robots encounter instances of novel classes that are considered to be unknowns w.r.t. the pre-defined class vocabulary. To address this unrealistic assumption, we study LPS in the Open World (LiPSOW): we train models on a dataset with a pre-defined semantic class vocabulary and study their generalization to a larger dataset where novel instances of thing and stuff classes can appear. This experimental setting leads to interesting conclusions. While prior art train class-specific instance segmentation methods and obtain state-of-the-art results on known classes, methods based on class-agnostic bottom-up grouping perform favorably on classes outside of the initial class vocabulary (i.e., unknown classes). Unfortunately, these methods do not perform on-par with fully data-driven methods on known classes. Our work suggests a middle ground: we perform class-agnostic point clustering and over-segment the input cloud in a hierarchical fashion, followed by binary point segment classification, akin to Region Proposal Network [1]. We obtain the final point cloud segmentation by computing a cut in the weighted hierarchical tree of point segments, independently of semantic classification. Remarkably, this unified approach leads to strong performance on both known and unknown classes.
Comment: Pre-print. Accepted in the International Journal of Computer Vision, 19 Sept 2024. Code available at https://github.com/g-meghana-reddy/open-world-panoptic-segmentation
Document Type: Working Paper
DOI: 10.1007/s11263-024-02166-9
Access URL: http://arxiv.org/abs/2409.14273
Accession Number: edsarx.2409.14273
Database: arXiv
More Details
DOI:10.1007/s11263-024-02166-9