Application of spectral imaging to electronic endoscopes

Abstract

This chapter deals with image acquisition by CCD-based electronic endoscopes, developed from color film-based recording devices called gastrocameras. The quality of color images, particularly reproduced colors, is influenced significantly by the spectral characteristics of imaging devices, as well as illumination and visual environments. Thus, recording and reproduction of spectral information on the object rather than information on three primary colors (RGB) is required in electronic museums, digital archives, electronic commerce, telemedicine, and electronic endoscopy in which recording and reproduction of high-definition color images are necessary. We have been leading the world in developing five-band spectral cameras for digital archiving (Miyake, Analysis and evaluation of digital color images, 2000; Miyake, Manual of spectral image processing, 2006; Miyake and Yokoyama, Obtaining and reproduction of accurate color images based on human perception, pp 190-197, 1998). Spectral information includes information on all visible light from the object and may be used for new types of recording, measurement, and diagnosis that cannot be achieved with the three primary colors of RGB or CMY. This chapter outlines the principle of FICE (flexible spectral imaging color enhancement), a spectral endoscopic image processing that incorporates such spectral information for the first time.