LiDAR Data Synthesis with Denoising Diffusion Probabilistic Models
Kazuto Nakashima, Ryo Kurazume
TL;DR
This work addresses the challenge of generating realistic LiDAR data by introducing R2DM, a denoising diffusion probabilistic model that operates on a range–reflectance image representation. By incorporating explicit spatial bias through Fourier features (and spherical-harmonics variants) and a carefully designed data representation, R2DM achieves state-of-the-art fidelity and efficiency on KITTI-360 and KITTI-Raw, outperforming prior diffusion and GAN-based approaches. The authors further extend the model to a flexible LiDAR completion pipeline using RePaint, enabling robust beam-level upsampling under various corruptions. Overall, R2DM advances high-fidelity LiDAR synthesis and restoration with practical implications for scalable simulation and perception tasks in autonomous systems.
Abstract
Generative modeling of 3D LiDAR data is an emerging task with promising applications for autonomous mobile robots, such as scalable simulation, scene manipulation, and sparse-to-dense completion of LiDAR point clouds. While existing approaches have demonstrated the feasibility of image-based LiDAR data generation using deep generative models, they still struggle with fidelity and training stability. In this work, we present R2DM, a novel generative model for LiDAR data that can generate diverse and high-fidelity 3D scene point clouds based on the image representation of range and reflectance intensity. Our method is built upon denoising diffusion probabilistic models (DDPMs), which have shown impressive results among generative model frameworks in recent years. To effectively train DDPMs in the LiDAR domain, we first conduct an in-depth analysis of data representation, loss functions, and spatial inductive biases. Leveraging our R2DM model, we also introduce a flexible LiDAR completion pipeline based on the powerful capabilities of DDPMs. We demonstrate that our method surpasses existing methods in generating tasks on the KITTI-360 and KITTI-Raw datasets, as well as in the completion task on the KITTI-360 dataset. Our project page can be found at https://kazuto1011.github.io/r2dm.
