Increasing the image resolution using multi-windows spline-type spaces

•The paper proposes a method to increase the resolution of an image at the time of the acquisition.•The algorithm is computationally efficient due to the fast computation of the duals in spline-type spaces with multiple generators.•Experiments on synthetic and astronomical optical images are performed in order to validate the method.

The aim of this paper is to introduce a computational efficient method to increase the resolution of an image together with an automatic registration with subpixel accuracy. The algorithm makes use of a priori knowledge of the offsets for a set of digital images and the fast computation of the duals in spline-type spaces with multiple generators. These spaces are obtained by applying a discrete group of translation operators to a finite set of smooth functions, forming a Riesz basis for its closed linear span within the Hilbert space L2(R2)L2(R2). Experiments on synthetic and astronomical optical images are presented.