SIFT—Scale-Invariant Local Features

Abstract

Many real applications require the localization of reference positions in one or more images, for example, for image alignment, removing distortions, object tracking, 3D reconstruction etc. We have seen that corner points can be located quite reliably and independent to orientation. However, typical corner detectors only provide the position and strength of each candidate point but do not provide any information about its characteristic or “identity” that could be used for matching. Another limitation is that most corner detectors only operate at a particular scale or resolution, since they are based on a rigid set of filters.