A Scale-space Approach for Surface Normal Vector Estimation from Depth Maps

Abstract

Surface normal vectors provide cues about the local geometric features of the scene which are utilized in many computer vision and computer graphics applications. Thus, the estimation of surface normals by utilizing structured range sensor data is an important research field. Thereupon, we propose a learning-free algorithm to estimate the surface normal vectors from depth maps. Our simple yet effective method relies on computations carried out in scale-space. Our main idea is to estimate the surface normals which cannot be properly computed in the finest scale from the coarser scales. Our method can estimate the surface normals even for images included in datasets that have challenging characteristics such as noisy real-world data or significantly large planar regions that either have a small or no gradient change. We analyze our algorithm’s performance by utilizing five benchmarks, namely, the MIT-Berkeley Intrinsic Images dataset, the New Tsukuba Dataset, the SceneNet RGB-D dataset, the IID-NORD dataset, and the NYU Depth Dataset V2, and by using two different evaluation strategies. According to the experimental results, our method can estimate surface normals efficiently without requiring neither complex computations nor huge amounts of data.