Open Access

Adaptive Outlier Rejection in Image Super-resolution

  • Mejdi Trimeche1Email author,
  • Radu Ciprian Bilcu1 and
  • Jukka Yrjänäinen2
EURASIP Journal on Advances in Signal Processing20062006:038052

Received: 29 November 2004

Accepted: 27 May 2005

Published: 20 February 2006


One critical aspect to achieve efficient implementations of image super-resolution is the need for accurate subpixel registration of the input images. The overall performance of super-resolution algorithms is particularly degraded in the presence of persistent outliers, for which registration has failed. To enhance the robustness of processing against this problem, we propose in this paper an integrated adaptive filtering method to reject the outlier image regions. In the process of combining the gradient images due to each low-resolution image, we use adaptive FIR filtering. The coefficients of the FIR filter are updated using the LMS algorithm, which automatically isolates the outlier image regions by decreasing the corresponding coefficients. The adaptation criterion of the LMS estimator is the error between the median of the samples from the LR images and the output of the FIR filter. Through simulated experiments on synthetic images and on real camera images, we show that the proposed technique performs well in the presence of motion outliers. This relatively simple and fast mechanism enables to add robustness in practical implementations of image super-resolution, while still being effective against Gaussian noise in the image formation model.


Authors’ Affiliations

Multimedia Technologies Laboratory, Nokia Research Center
Symbian Product Platforms, Nokia Technology Platforms


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© Mejdi Trimeche et al. 2006

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.