One Shot Photometric Stereo from Reflectance Classification
Toshiya Kawabata, Fumihiko Sakaue and Jun Sato
Department of Computer Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Keywords:
Photometric Stereo, Multi-band Imaging, Multi-band Lighting, Photometric Analysis.
Abstract:
3D reconstruction of object shape is one of the most important problem in the field of computer vision. Espe-
cially, estimation of normal orientation of object surface is useful for photo-realistic image rendering. For this
estimation, the photometric stereo is often used. However, it requires multiple images taken under different
lighting conditions in the same pose, and thus, we cannot apply it to moving objects in general. In this pa-
per, we propose a one-shot photometric stereo for estimating surface normal of moving objects with arbitrary
textures. In our method, we estimate surface orientation and reflectance property simultaneously. For this
objective, reflectance data set is used for decreasing DoF (Degree of Freedom) of estimation. In addition, we
classify reflectance property of an input image into limited number of classes. By using the prior knowledge,
our method can estimate surface orientation and reflectance property, even if input information is not sufficient
for the estimation.
1 INTRODUCTION
In the field of computer vision, 3D reconstruction
is one of the most important problems. In ordinary
case, several numbers of images are taken under dif-
ferent imaging condition, and then, 3D shape is re-
constructed from these images. In general, stereo
method from multiple cameras is used for 3D re-
construction(Agarwal et al., 2011; Newcombe et al.,
2011). In these methods, correspondences are de-
tected from images, and 3D shape is reconstructed
from the correspondences(Hartley and Zisserman,
2000). In particular, multi-baseline stereo method
with bundle adjustment is widely used for 3D recon-
struction(Agarwal et al., 2011). Furthermore, dense
3D reconstruction by using a moving camera is also
proposed(Newcombe et al., 2011).
The 3D reconstruction is useful for obtaining 3D
shape of objects, since we need just cameras. How-
ever, the accuracy of results is often not sufficient for
recovering surface orientation. The surface orienta-
tion can be estimated by differentiating 3D shapes,
and thus we need very accurate 3D shapes for ob-
taining accurate surface orientations. The surface re-
construction is important for synthesizing realistic 3D
graphics because photometric property, such as shad-
ing, on object depends mostly on surface orientations.
Thus, accurate estimating methods of surface orienta-
tion are required.
The photometric stereo method(Chen et al., 2011;
Anderson et al., 2011) is widely used for surface ori-
entation estimation. The method can estimate surface
orientation directly from a set of images taken under
different lighting conditions. In ordinary case, a cam-
era and a target object are fixed and just lighting con-
dition changes for the estimation.
Although the method works well for static scenes,
it cannot work for dynamic scenes, since images are
taken under not only different lighting conditions but
also different poses in the case of dynamic scenes.
Thus, we cannot reconstruct surface orientation of dy-
namic scenes from these images.
For reconstructing 3D surface of dynamic scenes,
we need to obtain multiple images under different
lighting conditions simultaneously. For this objec-
tive, some methods are recently proposed. Chen et
al.(Chen et al., 2011) proposed image demultiplex-
ing method for photometric stereo. In this method,
special periodic patterns are projected from projec-
tors to target scene simultaneously. By demultiplex-
ing an observed image, we can obtain multiple im-
ages taken under different lighting from a single im-
age. Although the method works well even if the
target scenes change dynamically, it does not work
when scene include complex texture. Anderson et
al.(Anderson et al., 2011) proposed a method using
multiple colored lights. In this method, a single im-
age is divided into multiple images illuminated un-
der different conditions by using color information.
Furthermore, Brostow et al.(Brostow et al., 2011) ex-
One Shot Photometric Stereo from Reflectance Classification.