A novel super resolution reconstruction of low reoslution images progressively using dct and zonal filter based denoising

Liyakathunisa; C. N . Ravi Kumar

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arXiv · 1102.5688

A novel super resolution reconstruction of low reoslution images progressively using dct and zonal filter based denoising

Liyakathunisa·C. N . Ravi Kumar

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Abstract

Due to the factors like processing power limitations and channel capabilities images are often down sampled and transmitted at low bit rates resulting in a low resolution compressed image. High resolution images can be reconstructed from several blurred, noisy and down sampled low resolution images using a computational process know as super resolution reconstruction. Super-resolution is the process of combining multiple aliased low-quality images to produce a high resolution, high-quality image. The problem of recovering a high resolution image progressively from a sequence of low resolution compressed images is considered. In this paper we propose a novel DCT based progressive image display algorithm by stressing on the encoding and decoding process. At the encoder we consider a set of low resolution images which are corrupted by additive white Gaussian noise and motion blur. The low resolution images are compressed using 8 by 8 blocks DCT and noise is filtered using our proposed novel zonal filter. Multiframe fusion is performed in order to obtain a single noise free image. At the decoder the image is reconstructed progressively by transmitting the coarser image first followed by the detail image. And finally a super resolution image is reconstructed by applying our proposed novel adaptive interpolation technique. We have performed both objective and subjective analysis of the reconstructed image, and the resultant image has better super resolution factor, and a higher ISNR and PSNR. A comparative study done with Iterative Back Projection (IBP) and Projection on to Convex Sets (POCS),Papoulis Grechberg, FFT based Super resolution Reconstruction shows that our method has out performed the previous contributions.

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BibTeX RIS

Liyakathunisa, C. N . Ravi Kumar. 2011-02-28. A novel super resolution reconstruction of low reoslution images progressively using dct and zonal filter based denoising. https://arxiv.org/abs/1102.5688

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