2011 Fiscal Year Final Research Report

Photometric estimation for outdoor scene

Research Project

Project/Area Number	22700180
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Perception information processing/Intelligent robotics
Research Institution	Nara Institute of Science and Technology
Principal Investigator	TAKAMATSU Jun 奈良先端科学技術大学院大学, 情報科学研究科, 准教授 (90510884)
Project Period (FY)	2010 – 2011
Keywords	コンピュータビジョン / フォトメトリ / 屋外環境
Research Abstract	We propose a method for estimating inherent surface color robustly against image noises from two registered images taken under different outdoor illuminations. We formulate the likelihood based on maximum likelihood manner while considering both inter-pixel and intra-pixel relationships. We define inter-pixel relationship based on stochastic behavior of image noises and properties of outdoor illumination chromaticity. We rely on the spatial continuity of both surface color and illumination to define intra-pixel relationship. We also propose to maximize the likelihood function in two step manner. Experimental results demonstrate the significant improvement of the proposed method in estimation accuracy compared to previous methods.