A Simple Model for On-Sensor Phase-Detection Autofocusing Algorithm


A simple model of the phase-detection autofocus device based on the partially masked sensor pixels is described. The cross-correlation function of the half-images registered by the masked pixels is proposed as a focus function. It is shown that—in such setting—focusing is equivalent to searching of the cross-correlation function maximum. Application of stochastic approximation algorithms to unimodal and non-unimodal focus functions is shortly discussed.

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Śliwiński, P. and Wachel, P. (2013) A Simple Model for On-Sensor Phase-Detection Autofocusing Algorithm. Journal of Computer and Communications, 1, 11-17. doi: 10.4236/jcc.2013.16003.

Conflicts of Interest

The authors declare no conflicts of interest.


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