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46
A Survey of Image Registration Techniques
 ACM Computing Surveys
, 1992
"... 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 ..."
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Cited by 964 (2 self)
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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. 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....
Processing images and video for an impressionist effect
 In Proc. ACM SIGGRAPH
, 1997
"... This paper describes a technique that transforms ordinary video segments into animations that have a handpainted look. Our method is the first to exploit temporal coherence in video clips to design an automatic filter with a handdrawn animation quality, in this case, one that produces an Impressio ..."
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Cited by 190 (1 self)
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This paper describes a technique that transforms ordinary video segments into animations that have a handpainted look. Our method is the first to exploit temporal coherence in video clips to design an automatic filter with a handdrawn animation quality, in this case, one that produces an Impressionist effect. Offtheshelf image processing and rendering techniques are employed, modified and combined in a novel way. This paper proceeds through the process step by step, providing helpful hints for tuning the offtheshelf parts as well as describing the new techniques and bookkeeping used to glue the parts together. 1.
Scattered Data Interpolation with Multilevel Splines
 IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS
, 1997
"... This paper describes a fast algorithm for scattered data interpolation and approximation. Multilevel Bsplines are introduced to compute a C²continuous surface through a set of irregularly spaced points. The algorithm makes use of a coarsetofine hierarchy of control lattices to generate a sequen ..."
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Cited by 158 (10 self)
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This paper describes a fast algorithm for scattered data interpolation and approximation. Multilevel Bsplines are introduced to compute a C²continuous surface through a set of irregularly spaced points. The algorithm makes use of a coarsetofine hierarchy of control lattices to generate a sequence of bicubic Bspline functions whose sum approaches the desired interpolation function. Large performance gains are realized by using Bspline refinement to reduce the sum of these functions into one equivalent Bspline function. Experimental results demonstrate that highfidelity reconstruction is possible from a selected set of sparse and irregular samples.
Automatic Smoothing Spline Projection Pursuit
 Journal of Computational and Graphical Statistics
, 1994
"... A highly flexible nonparametric regression model for predicting a response y given covariates fx k g d k=1 is the projection pursuit regression (PPR) model y = h(x) = fi 0 + P j fi j f j (ff T j x), where the f j are general smooth functions with mean zero and norm one, and P d k=1 ff 2 k ..."
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Cited by 18 (1 self)
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A highly flexible nonparametric regression model for predicting a response y given covariates fx k g d k=1 is the projection pursuit regression (PPR) model y = h(x) = fi 0 + P j fi j f j (ff T j x), where the f j are general smooth functions with mean zero and norm one, and P d k=1 ff 2 kj = 1. The standard PPR algorithm of Friedman and Stuetzle (1981) estimates the smooth functions f j using the supersmoother nonparametric scatterplot smoother. Friedman's algorithm constructs a model with M max linear combinations, then prunes back to a simpler model of size M M max , where M and M max are specified by the user. This paper discusses an alternative algorithm in which the smooth functions are estimated using smoothing splines. The direction coefficients ff j , the amount of smoothing in each direction, and the number of terms M and M max are determined to optimize a single generalized crossvalidation measure. To appear as: Roosen, C. B. and Hastie, T. J. (1994). Automat...
AN EXTENSION OF CHEBFUN TO TWO DIMENSIONS
"... An objectoriented Matlab system is described that extends the capabilities of Chebfun to smooth functions of two variables defined on rectangles. Functions are approximated to essentially machine precision by using iterative Gaussian elimination with complete pivoting to form “chebfun2 ” objects ..."
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Cited by 7 (5 self)
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An objectoriented Matlab system is described that extends the capabilities of Chebfun to smooth functions of two variables defined on rectangles. Functions are approximated to essentially machine precision by using iterative Gaussian elimination with complete pivoting to form “chebfun2 ” objects representing low rank approximations. Operations such as integration, differentiation, function evaluation, and transforms are particularly efficient. Global optimization, the singular value decomposition, and rootfinding are also extended to chebfun2 objects. Numerical applications are presented.
Local hybrid approximation for scattered data fitting with bivariate splines
 Comput. Aided Geom. Design
, 2006
"... We suggest a local hybrid approximation scheme based on polynomials and radial basis functions, and use it to improve the scattered data fitting algorithm of [7]. Similar to that algorithm, the new method has linear computational complexity and is therefore suitable for large real world data. Numeri ..."
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Cited by 5 (3 self)
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We suggest a local hybrid approximation scheme based on polynomials and radial basis functions, and use it to improve the scattered data fitting algorithm of [7]. Similar to that algorithm, the new method has linear computational complexity and is therefore suitable for large real world data. Numerical examples suggest that it can produce high quality artifact–free approximations that are more accurate than those given by the original method where pure polynomial local approximations are used.
Image Registration using Multiquadric Functions, the Finite Element Method, Bivariate Mapping Polynomials and the Thin Plate Spline
, 1996
"... In this report, three methods of imagetoimage registration using control points are evaluated. We assume that ephemeris sensor and platform data are unavailable. These techniques are the polynomial method, the piecewise linear transformation and the multiquadric method. The motivation for this res ..."
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Cited by 4 (0 self)
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In this report, three methods of imagetoimage registration using control points are evaluated. We assume that ephemeris sensor and platform data are unavailable. These techniques are the polynomial method, the piecewise linear transformation and the multiquadric method. The motivation for this research is the need for more accurate geometric correction of digital remote sensing data. This is especially important for airborne scanned imagery which is characterized by greater distortions than satellite data. The polynomial and piecewise linear methods were developed for use with satellite imagery and have remained popular due to their relative simplicity in theory and implementation. With respect to airborne data however, both of these methods have serious shortcomings. The polynomial method, a global model, is generally applied as a leastsquares approximation to the control points. Mathematically it is unconstrained between points leading to undesirable excursions in the warp. The p...
A flexible Krylov solver for shifted systems with application to oscillatory hydraulic tomography
 SIAM J. Sci. Comput
"... We discuss efficient solutions to systems of shifted linear systems arising in computations for oscillatory hydraulic tomography (OHT). The reconstruction of hydrogeological parameters such as hydraulic conductivity and specific storage using limited discrete measurements of pressure (head) obtai ..."
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Cited by 3 (1 self)
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We discuss efficient solutions to systems of shifted linear systems arising in computations for oscillatory hydraulic tomography (OHT). The reconstruction of hydrogeological parameters such as hydraulic conductivity and specific storage using limited discrete measurements of pressure (head) obtained from sequential oscillatory pumping tests, leads to a nonlinear inverse problem. We tackle this using the quasilinear geostatistical approach [15]. This method requires repeated solution of the forward (and adjoint) problem for multiple frequencies, for which we use flexible preconditioned Krylov subspace solvers specifically designed for shifted systems based on ideas in [13]. The solvers allow the preconditioner to change at each iteration. We analyze the convergence of the solver and perform an error analysis when an iterative solver is used for inverting the preconditioner matrices. Finally, we apply our algorithm to a challenging application taken from oscillatory hydraulic tomography to demonstrate the computational gains by using the resulting method. 1
Padua2DM: fast interpolation and cubature at the Padua points in Matlab/Octave
 NUMERICAL ALGORITHMS
, 2010
"... We have implemented in Matlab/Octave two fast algorithms for bivariate Lagrange interpolation at the socalled Padua points on rectangles, and the corresponding versions for algebraic cubature. ..."
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Cited by 3 (1 self)
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We have implemented in Matlab/Octave two fast algorithms for bivariate Lagrange interpolation at the socalled Padua points on rectangles, and the corresponding versions for algebraic cubature.