Ricerc@Sapienza

In this paper local and non-local denoising methods are jointly employed in order to improve the visual quality of the final denoised image. Based on the evidence that the output images of non local denoising methods are not pointwise better everywhere than the outputs images of local methods and than the noisy image itself, the cascade of two improvement steps is applied to the output image of a non local denoising method. The first step aims at correcting the output image by recovering the lost information directly from the noisy one.

Synthesis-by-analysis is a well established paradigm for reproduction of textures having random appearance. In this contribution, in order to simplify the overall procedure in the case of colored textures, we exploit the second-order correlation existing between the texture chrominance and luminance components. Specifically, we perform the synthesis exclusively on the luminance component, while the chrominance components are reproduced by applying properly designed Wiener filters, whose coefficients have been previously calculated in the analysis stage.