Patent ID: 7162099
Filing Date: 2007-01-09
Classification: G06T,H04N

Abstract:
1. An N-dimensional filter having a transmission function for applying noise reduction to an original image pixel p being provided to the N-dimensional filter by a received input signal, wherein at least one filter coefficient of the transmission function is defined such that the transmission function applies both noise reduction and sharpness enhancement, simultaneously, to the signal input to said N-dimensional filter, and wherein the transmission function is defined as follows: wherein p(x,y,t): represents the spatial and temporal position of the original or a neighbor pixel; N1, N2: are vectors defining a one, two or three dimensional neighborhood of the original pixel; n represents the position of a current neighbor pixel in a neighborhood N1, N2; G(p): is a normalization factor; α, β: are groups of filter coefficients α(p, n) and β(p, n) of the transmission function; γ, δ: are constants; and F(p): is an input luminance signal applied to said N-dimensional filter, characterized in that α(p, n) represent the filter-coefficients of a first group a of filter coefficients and being defined as: and β(p, n) represent the filter-coefficients of a second group β of filter coefficients and being defined as: wherein: Th 1 –Th 4 : are threshold values, P: is a negative programmable parameter, and w1, w2: are positive programmable parameters; and wherein the parameters Δ and Δ f are defined as follows: