Document Type

Article

Publication Date

12-2007

Publication Source

IEEE Transactions on Image Processing

Abstract

A computationally simple super-resolution algorithm using a type of adaptive Wiener filter is proposed. The algorithm produces an improved resolution image from a sequence of low-resolution (LR) video frames with overlapping field of view. The algorithm uses subpixel registration to position each LR pixel value on a common spatial grid that is referenced to the average position of the input frames. The positions of the LR pixels are not quantized to a finite grid as with some previous techniques. The output high-resolution (HR) pixels are obtained using a weighted sum of LR pixels in a local moving window. Using a statistical model, the weights for each HR pixel are designed to minimize the mean squared error and they depend on the relative positions of the surrounding LR pixels. Thus, these weights adapt spatially and temporally to changing distributions of LR pixels due to varying motion. Both a global and spatially varying statistical model are considered here. Since the weights adapt with distribution of LR pixels, it is quite robust and will not become unstable when an unfavorable distribution of LR pixels is observed. For translational motion, the algorithm has a low computational complexity and may be readily suitable for real-time and/or near real-time processing applications. With other motion models, the computational complexity goes up significantly. However, regardless of the motion model, the algorithm lends itself to parallel implementation. The efficacy of the proposed algorithm is demonstrated here in a number of experimental results using simulated and real video sequences. A computational analysis is also presented.

Inclusive pages

2953-2964

ISBN/ISSN

1057-7149

Document Version

Postprint

Comments

The paper available for download is the authors' accepted manuscript, included in the repository in compliance with IEEE policies on archiving. The version of record may contain minor differences that have come about in the copy editing and layout processes. Permission documentation is on file.

Publisher

IEEE: Institute of Electrical and Electronics Engineers

Volume

16

Issue

12

Peer Reviewed

yes