The registration of correlation signals with high dynamic range leads to increase of recognition's accuracy and robustness. Digital photo sensors with common Bayer colour filter array can be used for this purpose. In case of quasimonochromatic illumination used in optical-digital correlator, it is possible to register correlation signals with high dynamic range. For signal's registration it can be used not only colour channel, which corresponded to the wavelength of illumination, but other colour channels too. In this work the application of the spatially varying pixels exposures technique for obtaining linear high dynamic range images of correlation signals from digital photo sensors with Bayer mosaic is presented. Bayer colour filters array is considered as an array of attenuating filters in a quasimonochromatic light. Images are reconstructed using information from all colour channels and correction coeficients that obtained at the preliminary calibration step. The registered image of the correlation signal is mapped to the linear high dynamic range image using a simple and eficient algorithm. Calibration procedure for correction coeficients obtaining is described. Quantitative estimation of optical-digital correlator's accuracy is provided. Experimental results on obtaining images of correlation signals with linear high dynamic range are presented.

Date Published: 19 January 2009
PDF: 10 pages
Proc. SPIE 7252, Intelligent Robots and Computer Vision XXVI: Algorithms and Techniques, 72520V (19 January 2009); doi: 10.1117/12.805837

Published in SPIE Proceedings Vol. 7252:
Intelligent Robots and Computer Vision XXVI: Algorithms and Techniques
David P. Casasent; Ernest L. Hall; Juha Röning, Editor(s)