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... the motion in the sequence, followed by a fusion of the inputs according to these motion vectors. A wide variety of super resolution algorithms have been developed in the past 2 decades; we refer to =-=[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]-=- as representatives of this vast literature. In the currently available super-resolution algorithms, only global motion estimation (e.g. 2translation or affine global warp) is accurate enough to lead...

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...EEE, and Gene Golub Abstract—Superresolution reconstruction produces a high-resolution image from a set of low-resolution images. Previous iterative methods for superresolution [9], [11], [18], [27], =-=[30]-=- had not adequately addressed the computational and numerical issues for this ill-conditioned and typically underdetermined large scale problem. We propose efficient block circulant preconditioners fo...

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...prior. This sub-space can be learnt from image examples. The methods are applied to both real and synthetic images of text and faces, and results are compared to Schultz and Stevenson's MAP estimator =-=[15]-=-. We consider in particular images of scenes for which the point-to-point mapping is a plane projective transformation which has 8 degrees of freedom. In the real image examples, registration is obtai...

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...d image super-resolution algorithm, the essential issue is how to apply a good prior or constraint on the HR image because of the ill-posedness of the image super-resolution. Generic smoothness prior =-=[25, 11]-=- and edge smoothness prior [21, 1, 6, 7, 22, 27] are two widely used priors. In this paper, we propose a novel generic image prior — gradient profile prior for the gradient field of the natural imp(x0...

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...mposing a first order smoothness constraint in the reconstructed high-resolution image. In this case the PSF can be obtained from the bench calibration of the satellite optics. 19Schultz & Stevenson =-=[132]-=- propose a MAP estimation method which differs from previous ones in two significant respects. Firstly, it does not use a geometric registration method, but a general full, dense correspondence method...

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...he prior may be chosen to ensure a convex optimization in (5) enabling the use of descent optimization procedures. Examples of the application of Bayesian methods to SR reconstruction may be found in =-=[15]-=- using a Huber MRF and [3, 7] with a Gaussian MRF. Maximum likelihood (ML) estimation has also been applied to SR reconstruction [18]. ML estimation is a special case of MAP estimation (no prior term)...

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...following finitedifferences in the 4 adjacent, unique pair-cliques : d x = f x+1;y f x;y d y = f x;y+1 f x;y d xy = 1 p 2 (f x+1;y+1 f x;y ) d yx = 1 p 2 (f x+1;y 1 f x;y ) (10) Schultz and Stevenson =-=[27]-=- suggest a prior based on 2nd derivatives, in which the spatial activity measures are defined over triplet-cliques. Huber MRFs A common criticism levelled at the GMRF priors is that the associated MAP...

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...es undergoing similarity [9] and affine [10] transformations. Mann and Picard [12] extended this work to include projective transformations. Other authors have considered non-parametric motion models =-=[16]-=- and region /contour tracking [1]. Various imaging degradation models have been used. Irani and Peleg modelled image degradations including both optical blur and spatial quantization. The techniques w...

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...the combined information available at the different sets of sampling points. Examples of such SR procedures can be found in studies conducted at NASA on satellite images [4], by Schultz and Stevenson =-=[25]-=- processing a series of movie frames and by [8]. B. The Proposed Scheme: Single Image SR We elaborate an approach suitable for SR based on a single image, similarly to [32]. Instead of using a sequenc...