This work deals with noise removal by the use of an edge preserving method called Perona–Malik diffusion or anisotropic diffusion[2][3]. This technique is used for image restoration without removing significant parts of the image content, typically edges or other details. In this scheme anisotropic diffusion is performed on DWT domain[1][7] which is more stationary than noisy image domain. In DWT domain noise decreases with increase in scale and at each scale, noise has less influence on the PDE than that in the image domain. Experimental results have shown that the proposed algorithm can significantly reduce noise while image edges are preserved.

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Perona–malik Diffusion dwt image Restoration.