Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Invariant representation for spectral reflectance images and its application | Ibrahim et al. EURASIP Journal on Image and Video Processing 2011 2011 2 http content 2011 1 2 D EURASIP Journal on Image and Video Processing a SpringerOpen Journal RESEARCH Open Access Invariant representation for spectral reflectance images and its application Abdelhameed Ibrahim1 2 Shoji Tominaga1 and Takahiko Horiuchi1 Abstract Spectral images as well as color images observed from object surfaces are much influenced by various illumination conditions such as shading and specular highlight. Several invariant representations were proposed for these conditions using the standard dichromatic reflection model of dielectric materials. However these representations are inadequate for other materials like metal. This article proposes an invariant representation that is derived from the standard dichromatic reflection model for dielectric and the extended dichromatic reflection model for metal. We show that a normalized surface-spectral reflectance by the minimum reflectance is invariant to highlights shading surface geometry and illumination intensity. Here the illumination spectrum and the spectral sensitivity functions of the imaging system are measured in a separate way. As an application of the proposed invariant representation a segmentation algorithm based on the proposed representation is presented for effectively segmenting spectral images of natural scenes and bare circuit boards. Keywords Invariant representation dichromatic reflection models spectral imaging system spectral image segmentation Introduction Spectral images contain large amount of information compared with color images are useful for a variety of applications such as material identification natural scene rendering colorimetric analysis and machine vision tasks 1 . Spectral images as well as color images observed from object surfaces are much influenced by various illumination conditions. The observed spectral images do not only depend on surface-spectral reflectance .
