Hybrid model of diffusion based on the Jeffreys‐type equation for noise reduction on images. Issue 5 (1st May 2018)

• Record Type: Journal Article
• Authors: Loum, Georges Laussane; Pandry, Ghislain Koffi; Atiampo, Armand Kodjo; Oumtanaga, Souleymane
• Is Part Of: IET image processing. Volume 12:Issue 5(2018)
• Page Start: 716
• Page End: 728
• Publication Date: 2018-05-01
• Subjects: image denoising -- image restoration -- image filtering -- smoothing methods; hybrid diffusion model -- Jeffreys‐type equation -- image noise reduction -- image filtering -- image pre‐smoothing -- adaptive‐linear diffusion -- Jeffreys anisotropic diffusion -- variance absolute error -- smoothing filter -- Xu‐AD models -- A‐LD method -- stopping criterion; Image processing -- Periodicals; 621.36705
• DOI: 10.1049/iet-ipr.2017.0529
• Languages: English
• ISSNs: 1751-9659

Abstract

Abstract : Hybrid methods filtering of images generally put in collaboration two filters: the first is used for the pre‐smoothing and the second to finalise the filtering operation. This approach permits to smoothen the image efficiently while preserving at best its contours and fine structures. Unfortunately, the pre‐smoothing generally induces a blur which is not taken into account during the smoothing. In this study, the authors propose a hybrid diffusion method based on the Jeffreys‐type equation (JTE). The method proposed provides two steps: a pre‐smoothing stage called adaptive‐linear diffusion (A‐LD) and a smoothing stage called Jeffreys anisotropic diffusion (JAD). A stopping criterion for A‐LD, called variance absolute error (VAE) which estimates the noise level, is proposed in order to guarantee the optimality of the smoothing filter. A diffusion function is proposed as well in order to take into account the blurring induced by the pre‐smoothing. The proposed hybrid method is compared with the Perona and Malick, telegraph equation, artefact suppressed large‐scale non‐local means and Xu‐AD models. Experimental results show that the proposed hybrid method is efficient both on noise reduction and preservation of contours and fine structures.