Vladimir Alexandrovich BOCHKO^1*, Yoichi MIYAKE², and Jarmo Tapani ALANDER¹

¹Department of Electrical Engineering and Energy Technology, University of Vaasa, FIN-65101 Vaasa, Finland
²Research Center for Frontier Medical Engineering, Chiba University, Chiba 263-8522, Japan

(Received October 17, 2013; Accepted January 14, 2014)

A method of spectral reflectance estimation for electronic endoscopes is described. A new approach is proposed for the overfitting problem. We use a small training set. Initially, cross-validation is used to select model parameters. Then, for additional validation of the method a color image acquired under the same illumination as the training data is used. This additional color image gives a clear solution for both the estimation of spectra and the estimation of color reproduced from these spectra. Experiments confirm that the method predicts spectral reflectance and colors well. Accurate reproduction of endoscope images in different viewing conditions and under another light source was implemented using this approach.

Key words: electronic endoscope, spectral reflectance estimation, partial least-squares regression

^*E-mail address: vbochko@uva.fi