Patent ID: 7302110

Claim:
An image processing method comprising a transformation step of processing an input image signal to generate an adjusted output image signal, wherein the intensity values I(x,y) for different positions (x,y) of an image are adjusted to generate an adjusted intensity value I out (x,y) in accordance with: I out =Σ i=0 N α i ( I ) LPF Ω i [P i ( F ( I ))]· Q i ( F ( I ))+β( I ), where the P i (γ) form an orthogonal basis of functions of γ defined in a range 0<γ<1, the Q i (..) are antiderivatives of the P i (..): the Q i (F(I))=∫ 0 F(i) =P i (η)dη or approximations thereto, the LPF Ω [..] is an operator of low-pass spatial filtering; the Ω i are cut-off frequencies of the low-pass spatial filter, the F(..) is a weighting function, the α i (l) are i th members of a transformation step strength function, the β(I) is a strength function, the i and N are positive constants and the η is a variable.