Shoji Yamamoto, Naotaka Obara, Norimichi Tsumura, Toshiya Nakaguchi
Graduate School of Advanced Integrated Science, Chiba University, Inage-ku,
Chiba, Japan
The Journal of the institute of image electronics engineer of Japan (Accepted to be published in Vol.36, No.5, pp.641-649, 2007 ).
Abstract
We developed a efficient BTF compression and reproducing technique based on a dichromatic
reflection model. For the reproduction of the gloss appearance of rough
surface, Bi-directional Texture Function (BTF) rendering is thought to
be used in this system. However, efficient compression and reproduction
methods are required for real-time rendering. In this paper, we propose
an efficient approach of BTF rendering by separating the reflected light
to the specular, the cast shadow and the invariant diffuse elements. The
efficient compression for the BTF rendering is performed by applying the
Local Principal Component Analysis (LPCA) to the specular and the cast
shadow images, since their appearance depends on the direction of the viewing
or illumination. This method performs accurate reproduction by fewer principal
components in comparison with the conventional method. The final projection
image in an arbitrary direction of the viewing and illumination is synthesized
from the specular reflection image, the cast shadow image and the invariant
diffuse reflection image. Finally, the proposed method is implemented on
the appearance-based display, and demonstrated high-speed BTF
rendering which is two times faster than the conventional method.
Full paper ( to appeare )
[PDF] (in Japanese])