Automatic Radiometric Calibration in Photometric Stereo by Using Irradiance Consistency

概要

論文の詳細を見る
We propose a method for estimating the surface normals and camera response function simultaneously. In photometric stereo, camera is assumed to be radiometrically calibrated then the observed pixel intensity can be used to subsume the image irradiance. Our proposed method shows that such often time-consuming radiometric calibration can be avoided, while the camera response function and surface normals can be estimated at the same time. The key idea of our method is that the irradiance values converted from pixel values by radiometric response function must be equal to corresponding irradiance values calculated from the surface normals. We show that the simultaneous estimation can be expressed as a linear least-square problem with linear constraint. Finally, experiments on both synthetic images and real images demonstrate that our method can accurately estimate surface normals even when the images are captured by using uncalibrated camera with nonlinear radiometric response function.
2011-11-10