Image Registration for Multi-exposure High Dynamic Range Image Acquisition

Abstract

We present a fully automatic method for eliminating misalignments between a sequence of hand-held photographs taken at different exposures. The key component of the technique is the SIFT method that is employed to search for key-points (or feature-points) in consecutive images. The key-points are used to find matrices, that transform a set of images to a single coordinate system and eliminate any global misalignments (including general planar homography). We employ this technique to capture high dynamic range images from a set of photographs taken at different exposures, wheremisalignments can cause blurring and artifacts, and prevent achieving high quality HDR images. The proposed alignment technique works well for over- and under-exposed images and is not sensitive to an image content. We present our implementation of the technique and the results of tests made for variety of photographs.