Tackling Shapes and BRDFs Head-On

Abstract

In this work, we investigate the use of simple flash-based photography to capture an object's 3D shape and reflectance characteristics at the same time. The presented method is based on the principles of Structure from Motion (SfM) and Photometric Stereo (PS), yet, we make sure not to use more than readily-available consumer equipment, like a camera with flash. Starting from a SfM-generated mesh, we apply PS to refine both geometry and reflectance, where the latter is expressed in terms of data-driven Bidirectional Reflectance Distribution Function (BRDF) representations. We also introduce a novel approach to infer complete BRDFs starting from the sparsely sampled data-driven reflectance information captured with this setup. Our approach is experimentally validated by modeling several challenging objects, both synthetic and real.