Light of Normals: Unified Feature Representation for Universal
  Photometric Stereo
Authors: name: Hong Li, name: Houyuan Chen, name: Chongjie Ye, name: Zhaoxi Chen, name: Bohan Li, name: Shaocong Xu, name: Xianda Guo, name: Xuhui Liu, name: Yikai Wang, name: Baochang Zhang, name: Satoshi Ikehata, name: Boxin Shi, name: Anyi Rao, name: Hao Zhao

Universal photometric stereo (PS) aims to recover high-quality surface
normals from objects under arbitrary lighting conditions without relying on
specific illumination models. Despite recent advances such as SDM-UniPS and Uni
MS-PS, two fundamental challenges persist: 1) the deep coupling between varying
illumination and surface normal features, where ambiguity in observed intensity
makes it difficult to determine whether brightness variations stem from
lighting changes or surface orientation; and 2) the preservation of
high-frequency geometric details in complex surfaces, where intricate
geometries create self-shadowing, inter-reflections, and subtle normal
variations that conventional feature processing operations struggle to capture
accurately.