Patent ID: 7379615

Claim:
A method for a space-time filtering of noise in radiography comprising: a. for each pixel having coordinates (x,y) of a first image, a weighting is performed on coefficients U(k,l) of a first convolution core with a dimension D, equivalent to a low-pass filter, as a function of a coefficient G which is a function of a difference computed between I(x,y) and I(x+k, y+l), where I(x,y) is an intensity of the pixel with coordinates (x,y) of the first image, and k and l are indices used to explore the coefficients of the first convolution core, a second convolution core with coefficients Up(k,l) being thus obtained; b. for each pixel with coordinates (x,y) of the first image, a weighting is performed on the coefficients U(k,l) of the first convolution core as a function of the coefficient G which is a function of the difference computed between I(x,y) and I′(x+k, y+l), where I′(x,y) is an intensity of the pixel with coordinates (x,y) of a second image, a third convolution core with coefficients Up′(k,l) being thus obtained; and c. a filtered value of I(x,y) is computed by the formula: F ⁡ ( x , y ) = ( ∑ k = - L L ⁢ ⁢ ∑ l = - L L ⁢ ⁢ ( γ * Up ⁡ ( k , l ) . I ⁡ ( x + k , y + l ) + ( 1 - γ ) * Up ′ ⁡ ( k , l ) . I ′ ⁡ ( x + k , y + l ) ) ) / N ( 1 ) L =( D− 1)/2 (2) γ∈[0,1] (3) N = ∑ k = - L L ⁢ ⁢ ∑ l = - L L ⁢ ⁢ ( γ * Up ⁡ ( k , l ) + ( 1 - γ ) * Up ′ ⁡ ( k , l ) ) ( 4 ) where F(x,y) is the filtered value of I(x,y); and wherein D is greater than 1; wherein a value of γ is greater than 0 and less than 1.