Nonlinear image restoration is posed in terms of optimization by iterative computations. The iterative computations are decomposed spatially to develop an algorithm which is sensitive to local image variations. The application of this decomposed local algorithm to signal-dependent noise is discussed.
B. R. Hunt,
H. J. Trussell,
"Nonlinear Image Restoration With Signal-Dependent Noise", Proc. SPIE 0119, Applications of Digital Image Processing, (8 December 1977); doi: 10.1117/12.955722; https://doi.org/10.1117/12.955722