Digitalization of pixel shift in 3CCD camera-monitored images

Abstract

This paper describes a phenomenon "pixel shift" which sometimes occurs in images monitored by 3CCD Cameras and others. If there is such a pixel shift in the image, a user is suffering from a lack of precision of the image to be measured or utilized for image recognition and other image understanding. In a conventional approach, a specialist has determined whether pixel shift occurs or not in the image and he/she has reported performance evaluation for the relevant camera which monitors the image. This paper proposes a numerical method to detect occurrence of pixel shift in the image with Lagrange interpolation function, calculates the values of the level for occurrence of pixel shift quantitatively, and then compares the calculated results with the determination by specialist for 20 sample image files. The comparison results have good scores and support probability of a proposed approach to detect occurrence of pixel shift in the image without help from specialist. This paper calls the below sequence of procedure "digitalization of pixel shift", namely, 1) reading the values of R, G, and B signals from the target image, 2) selecting some sample values, 3) interpolating a suitable approximation function with the previous sample values, and 4) calculating numerically phase difference of R, G, B signals as the level for occurrence of pixel shift. © 2011 Springer-Verlag.