Image quality improvement of projection image under lighting condition
with color appearance model
Sayuri KAMIMIGAKI*, Keita HIRAI*, Shoji YAMAMOTO**, Keisuke TAKI*, Norimichi TSUMURA*, Toshiya NAKAGUCHI* and Yoichi MIYAKE***
(*)Graduate School of Advanced Integration Science, Chiba University
(**)Tokyo Metropolitan College of Industrial Technology
(***)Research Center for Frontier Medical Engineering, Chiba University
Journal of The Society of Photographic Science and Technology of Japan, Vol.73, No.2, pp.104-112, Apr. 2010
Abstract
We propose an image-quality improvement method of projected images under lighting conditions. In recent years, image quality of the projection display system has increasingly improved, and the system has come to widely use not only as projector but also television system. The color appearance and the resolution of the projected image, however, are influenced by the lighting conditions on the screen. Therefore, in this paper, the CIECAM02 color appearance model is introduced to improve both color and tone reproductions of the projected images under lighting conditions. Chromatic and achromatic channel responses in CIECAM02 are calculated from an input image under a lighting condition. The adapted achromatic response is used for tone mapping to preserve the detail components of the images. On the other hand, the adapted chromatic response is used for accurate color reproduction, which is optimized by the gamut compensation based on the difference between the gamut of projection color under lighting and dark conditions. For the validation, the original images and the corrected images by the proposed method are evaluated by subjective experiments using a paired comparison method. As a result, it is shown that the proposed method can improve the image quality under the lighting conditions.
Full paper ( to appeare )
[PDF] ( in Japanese )