Introduction

Abstract

With the proliferation of digital cameras, amateur photography is in the rise and among the vast amount of digital images generated, many are blurred due to camera shake. This is an expected phenomenon since lightweight cameras are more prone to movement and unless a tripod is used the chances for blurring is high. Object motion and camera defocus can also lead to a blurred image. Similar scenarios arise in medical, biological and astronomical imaging. Hence the image of a point source appears as a disc, and overlap of such discs from neighbouring pixels leads to blurring. In addition, in systems such as the wide-field microscope the light scattered from out of focus planes causes blurring and the out-of-focus light depends on the object being imaged. If the nature of the blur is known it is possible to use deconvolution to estimate the sharp image. However, in most cases it is difficult or impossible to know the blur. In such cases the only solution to obtain a sharper image is by using blind deconvolution, wherein one tries to reconstruct the original image without any knowledge of the way the camera/subject moved. This chapter explains the image formation model, how image degradation occurs, and an introduction to blind deconvolution.