Urban areas textural feature

We model the SPOT image with a 4-connected Gaussian Markov Random Field .

The associated distribution is given by :

The urban area textural feature is given by parameter T.

Using the Markov property, the local conditionnal law on the initial lattice is given by a normal law :

Computing the local conditionnal variance on the SPOT data, we get a first estimator :

We next consider the SPOT image on a decimated lattice, keeping one pixel out of two :

We compute the marginal law of the model on the decimated lattice. We obtain an 8-connected Gaussian Markov Random Field .

Using the Markov property, the local conditionnal law on the initial lattice is given by a normal law :

Computing the local conditionnal variance on the decimated SPOT data, we get a second estimator :

Combining the two variances we get a estimator of T :

SYNOPSIS OF THE DEMO