<title>Range estimation from camera blur by regularized adaptive identification</title>

Abstract

One of the fundamental problems of machine vision is the estimation of object depth from perceived images. This paper describes both an apparatus and the corresponding algorithms for the passive extraction of object depth. Here passive extraction implies the processing of images acquired using only the existing illumination, in this case uniform white light. Depth from defocus algorithms are extremely sensitive to image variations. Regularization, the application of a priori constraints, is employed to improve the accuracy of the range measurements. When the camera's point spread function is shift invariant, an adaptive algorithm is developed in the frequency domain. When the camera's point spread function is shift varying, an adaptive algorithm is developed in the spatial domain. Data is acquired from line scan cameras. Only a single range measurement or a single depth profile is extracted.