Holo-Relighting: Controllable Volumetric Portrait Relighting from a Single Image
Authors: Yiqun Mei, Yu Zeng, He Zhang, Zhixin Shu, Xuaner Zhang, Sai Bi, Jianming Zhang, HyunJoon Jung, Vishal M. Patel

At the core of portrait photography is the search for ideal lighting and viewpoint. The process often requires advanced knowledge in photography and an elaborate studio setup. In this work we propose Holo-Relighting a volumetric relighting method that is capable of synthesizing novel viewpoints and novel lighting from a single image. Holo-Relighting leverages the pretrained 3D GAN (EG3D) to reconstruct geometry and appearance from an input portrait as a set of 3D-aware features. We design a relighting module conditioned on a given lighting to process these features and predict a relit 3D representation in the form of a tri-plane which can render to an arbitrary viewpoint through volume rendering. Besides viewpoint and lighting control Holo-Relighting also takes the head pose as a condition to enable head-pose-dependent lighting effects. With these novel designs Holo-Relighting can generate complex non-Lambertian lighting effects (e.g. specular highlights and cast shadows) without using any explicit physical lighting priors. We train Holo-Relighting with data captured with a light stage and propose two data-rendering techniques to improve the data quality for training the volumetric relighting system. Through quantitative and qualitative experiments we demonstrate Holo-Relighting can achieve state-of-the-arts relighting quality with better photorealism 3D consistency and controllability.