cs.CVJun 3, 2025

AutoExpert: Automating 3D LiDAR Annotation from Expert-Crafted Guidelines

Authors: Yechi Ma, Wei Hua, Shu Kong

Organizations: Zhejiang University · University of Macau · Institute of Collaborative Innovation

Abstract

The contemporary paradigm of scaling data annotation, crucial for developing machine learning solutions, is to hire ordinary human annotators and instruct them with expert-crafted guidelines to label data. This paradigm is laborious, tedious, and costly, motivating us to study an open problem, auto-annotation with expert-crafted guidelines (dubbed AutoExpert). We develop benchmarks by redesigning the evaluation protocol and re-annotating data with nuScenes and PandaSet, two 3D detection datasets for autonomous driving research that provide expert-crafted annotation guidelines. Their guidelines define 18 and 25 object classes, respectively, using nuanced language descriptions and a few visual examples. Following the guidelines that require using 3D cuboids to label LiDAR data, AutoExpert requires algorithms to learn on few-shot labeled images and texts to perform the task of 3D detection on LiDAR data. Apparently, the challenges of AutoExpert lie in the data-modality and task discrepancy. Nevertheless, public foundation models (FMs) serve as promising tools to tackle these challenges. To address AutoExpert, we adopt a conceptually simple pipeline consisting of three components: (1) 2D object detection and segmentation in RGB images, (2) lifting 2D detections into 3D using known sensor poses, and (3) 3D cuboids generation for the 2D detections. Within this pipeline, we enhance and evaluate a variety of methods such as open-vocabulary detectors, few-shot detectors, and self-supervised learned detectors. We also develop novel techniques, leading to refined components that boost 3D detection mAP from 12.1 to 25.4 on the AutoExpert-nuScenes benchmark.

Figures & tables

Explore similar work

CardsList
  1. Open-vocabulary 3D object detection with promptable segmentation

    Sep 16, 2026Ömer Faruk Deniz, Mustafa Taha Koçyiğit3D Object DetectionObject Detection

  2. D3VL: Understanding Driving Scenes from 3D Time Series Data and Video with Language Models

    Jul 21, 2026Heesang Han, A. Lynn Abbott, Abhijit SarkarAutonomous DrivingWaymo Open Motion Dataset

  3. Auto-Labelling-Based Domain Transfer for 3D Object Detection on a Bicycle-Mounted LiDAR Platform

    Jun 24, 2026Mario Finkbeiner, Max A. Buettner, Kanak Mazumder +13D Object DetectionAutomotive Detection