A matrix based method for determining depth from focus

Abstract

The authors reveal some fundamental problems with inverse filtering: inaccuracies in finding the frequency-domain representation, windowing effects, and border effects. A general, matrix-based method using regularization that eliminates these problems is presented. The method is confirmed experimentally, with the results showing an RMS (root mean square) error of 1.3%.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>