Name
Abstract | ||
|---|---|---|
We propose a simple preconditioning method for accelerating the solution of edge-preserving image super-resolution (SR) problems in which a linear shift-invariant point spread function is employed. Our technique involves reordering the high-resolution (HR) pixels in a similar manner to what is done in preconditioning methods for quadratic SR formulations. However, due to the edge preserving requirements, the Hessian matrix of the cost function varies during the minimization process. We develop an efficient update scheme for the preconditioner in order to cope with this situation. Unlike some other acceleration strategies that round the displacement values between the low-resolution (LR) images on the HR grid, the proposed method does not sacrifice the optimality of the observation model. In addition, we describe a technique for preconditioning SR problems involving rational magnification factors. The use of such factors is motivated in part by the fact that, under certain circumstances, optimal SR zooms are nonintegers. We show that, by reordering the pixels of the LR images, the structure of the problem to solve is modified in such a way that preconditioners based on circulant operators can be used. |
Year | DOI | Venue |
|---|---|---|
2012 | 10.1109/TIP.2011.2160188 | IEEE Transactions on Image Processing |
Keywords | Field | DocType |
hessian matrix,hr grid,lr image,optimal sr zoom,edge-preserving image,preconditioning method,simple preconditioning method,preconditioning sr problem,quadratic sr formulation,super resolution,cost function,preconditioning,pixel,regularization,image restoration,edge detection,point spread function,high resolution,acceleration,minimisation,low resolution,image resolution,strontium | Computer vision,Preconditioner,Edge detection,Hessian matrix,Circulant matrix,Pixel,Artificial intelligence,Image restoration,Point spread function,Image resolution,Mathematics | Journal |
Volume | Issue | ISSN |
21 | 1 | 1941-0042 |
Citations | PageRank | References |
5 | 0.41 | 26 |
Authors | ||
2 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Stéphane Pelletier | 1 | 6 | 1.10 |
| Jeremy R. Cooperstock | 2 | 449 | 102.09 |