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Noise models

Noise in imaging systems is usually either additive or multiplicative. This thesis deals only with additive noise which is zero-mean and white. White noise is spatially uncorrelated: the noise for each pixel is independent and identically distributed (iid). Common noise models are:


Figure 1.2 illustrates these PDFs for zero-mean, unit variance noise.

Figure 1.2: Probability density functions of the Gaussian, Laplacian and Uniform distributions

Todd Veldhuizen
Fri Jan 16 15:16:31 EST 1998