A Survey of Image Registration Techniques

Registration is a fundamental task in image processing used to match two or more pictures taken, for example, at different times, from different sensors or from different viewpoints. Over the years, a broad range of techniques have been developed for the various types of data and problems. These techniques have been independently studied for several different applications resulting in a large body of research. This paper organizes this material by establishing the relationship between the distortions in the image and the type of registration techniques which are most suitable. Two major types of distortions are distinguished. The first type are those which are the source of misregistration. i.e., they are the cause of the misalignment between the two images. To register two images is to remove the effects of the source of misregistration. Distortions which are the source of misregistration determine the transformation class which will optimally align the two images. The transformation class in turn influences the general technique that should be taken. The second type of distortion are those which are not the source of misregistration. This type usually effects intensity values but they may also be spatial.