An Approximate Shading Model with Detail Decomposition for Object Relighting

TL;DR

This paper introduces a perceptually-inspired approximate shading model with detail decomposition for object relighting, enabling natural insertion and adjustment of objects in scenes through simple interactions.

Contribution

It proposes a novel shading model that combines 3D rendering and image-based composition, supporting flexible object relighting and insertion.

Findings

Quantitative evaluation shows improved realism.

User studies confirm natural appearance of relighted objects.

The model effectively decomposes shading for better manipulation.

Abstract

We present an object relighting system that allows an artist to select an object from an image and insert it into a target scene. Through simple interactions, the system can adjust illumination on the inserted object so that it appears naturally in the scene. To support image-based relighting, we build object model from the image, and propose a \emph{perceptually-inspired} approximate shading model for the relighting. It decomposes the shading field into (a) a rough shape term that can be reshaded, (b) a parametric shading detail that encodes missing features from the first term, and (c) a geometric detail term that captures fine-scale material properties. With this decomposition, the shading model combines 3D rendering and image-based composition and allows more flexible compositing than image-based methods. Quantitative evaluation and a set of user studies suggest our method is a promising alternative to existing methods of object insertion.