π€ AI Summary
Point cloudsβ unstructured geometry and absence of explicit global illumination modeling hinder accurate separation of albedo and shadows, limiting photorealistic applications such as relighting and texture editing. To address this, we propose IPCD-Netβthe first intrinsic decomposition network for point clouds that explicitly models global illumination direction. Leveraging a Projection-based Luminance Distribution (PLD) prior, IPCD-Net achieves high-fidelity decomposition on unstructured inputs via point-wise feature aggregation, multi-view projection, and hierarchical optimization. Trained on synthetic data and validated on real-world scenes, our method significantly suppresses cast shadows in estimated albedo, improves shadow color fidelity, and enhances cross-illumination registration accuracy. This work establishes a generalizable foundation for point cloud relighting and editing in AR and robotic applications.
π Abstract
Point clouds are widely used in various fields, including augmented reality (AR) and robotics, where relighting and texture editing are crucial for realistic visualization. Achieving these tasks requires accurately separating albedo from shade. However, performing this separation on point clouds presents two key challenges: (1) the non-grid structure of point clouds makes conventional image-based decomposition models ineffective, and (2) point-cloud models designed for other tasks do not explicitly consider global-light direction, resulting in inaccurate shade. In this paper, we introduce extbf{Intrinsic Point-Cloud Decomposition (IPCD)}, which extends image decomposition to the direct decomposition of colored point clouds into albedo and shade. To overcome challenge (1), we propose extbf{IPCD-Net} that extends image-based model with point-wise feature aggregation for non-grid data processing. For challenge (2), we introduce extbf{Projection-based Luminance Distribution (PLD)} with a hierarchical feature refinement, capturing global-light ques via multi-view projection. For comprehensive evaluation, we create a synthetic outdoor-scene dataset. Experimental results demonstrate that IPCD-Net reduces cast shadows in albedo and enhances color accuracy in shade. Furthermore, we showcase its applications in texture editing, relighting, and point-cloud registration under varying illumination. Finally, we verify the real-world applicability of IPCD-Net.