A compound Weibull model for SAR texture analysis

Introduces a new model for the statistic of the intensity of synthetic aperture radar (SAR) images. The model, named compound Weibull (CW) distribution, belongs to the well known class of the product models. According to this description the intensity, χ= τ·z, can be interpreted as the product of the variable z named ´speckle´, times the variable τ, referred to as ´texture´. The speckle, representing the effect of the coherent imaging, follows the chi-square distribution with 2L degrees of freedom for an L-look image and mean value 1. The texture, modulating the speckle variance, represents the observed scene and its probability density function (pdf) identifies the specific product model. Its mean value is the mean reflected power and its variance encodes the scene fluctuation. The most well-known product model is the K-distribution obtained with a gamma texture pdf