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arXiv · 1308.0608

Compression d'images par SVD et sur-approximation des composantes de chrominance

Henri Bruno Razafindradina·Paul Auguste Randriamitantsoa·Nicolas Raft Razafindrakoto
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Abstract

This paper gives a new scheme of colour image compression related to singular values matrix approximation. The image has to be converted in luminance / chrominance space before being processed like JPEG standard 4 : 2 : 0. Our approach is first based on a chrominance sub-sampling, then an over estimation of its singular values. Instead of keeping only the k first singular values for the 3 components R, G and B, we hold k first coefficients for the Y component and only k' (k' <= k) coefficients for 2 components Cb and Cr. Results show that for 512 x 512 pixels that, from k = 40 corresponding in an average distortion of 30 dB and a ratio of 15 : 1, the restored image has good quality. The algorithm allows a significant speed gain by sub-sampling too.

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Henri Bruno Razafindradina, Paul Auguste Randriamitantsoa, Nicolas Raft Razafindrakoto. 2013-08-02. Compression d'images par SVD et sur-approximation des composantes de chrominance. https://arxiv.org/abs/1308.0608

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