An Analog–Digital Hardware for L-Estimate Space-Varying Image Filtering


An analog–digital hardware solution for implementation of the L-estimate space-varying filtering has been proposed. The considered filter form is based on the robust space/spatial-frequency representation and provides efficient denoising of two-dimensional signals/images corrupted by heavy-tailed noise. Moreover, for images with fast-varying details and textures, the L-estimate filtering outperforms the commonly used filters. However, it requires significant processing time, since the space/spatial-frequency representation is calculated for each pixel, on a window by window basis. Therefore, in order to make it feasible for practical applications, a fast implementation of L-estimate space-varying filtering is proposed using a combined analog–digital approach. It provides efficient real-time processing of images corrupted by strong mixed Gaussian and impulse noise.

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Corresponding author

Correspondence to Irena Orović.

Additional information

This work is supported by the Montenegrin Ministry of Science, Project Grant: CS-ICT “New ICT Compressive sensing based trends applied to: multimedia, biomedicine and communications”.

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Orović, I., Lekić, N. & Stanković, S. An Analog–Digital Hardware for L-Estimate Space-Varying Image Filtering. Circuits Syst Signal Process 35, 409–420 (2016).

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  • Analog–digital hardware
  • Robust space/spatial-frequency distributions
  • L-estimate forms
  • Robust space-varying filtering