Umeyama Shinji, Godin Guy
Neuroscience Institute, The National Institute of Advanced Industrial Science and Technology, Tsukuba Central 2, Tsukuba, Ibaraki, 305-8568 Japan.
IEEE Trans Pattern Anal Mach Intell. 2004 May;26(5):639-47. doi: 10.1109/TPAMI.2004.1273960.
The image of an opaque object is created by observing the reflection of the light incident on its surface. The dichromatic reflection model describes the surface reflection as the sum of two components, diffuse and specular terms. The specular reflection component is usually strong in its intensity and polarized significantly compared to the diffuse components. On the other hand, the intensity of the diffuse component is weak and it tends to be unpolarized except near occluding contours. Thus, the observation of an object through a rotating polarizer approximately yields images containing constant diffuse component and specular component of different intensity. In this paper, we show that diffuse and specular components of surface reflection can be separated as two independent components when we apply Independent Component Analysis to the images observed through a polarizer of different orientations. We give a separation simulation of artificial data and also give some separation results of real scenes.
不透明物体的图像是通过观察入射到其表面的光的反射而形成的。二向色反射模型将表面反射描述为两个分量之和，即漫反射项和镜面反射项。镜面反射分量的强度通常很强，与漫反射分量相比，其偏振程度明显更高。另一方面，漫反射分量的强度较弱，除了在遮挡轮廓附近外，它往往是非偏振的。因此，通过旋转偏振器观察物体大致会产生包含恒定漫反射分量和不同强度镜面反射分量的图像。在本文中，我们表明，当我们将独立分量分析应用于通过不同方向偏振器观察到的图像时，表面反射的漫反射分量和镜面反射分量可以作为两个独立的分量分离出来。我们给出了人工数据的分离模拟，并给出了一些真实场景的分离结果。
