The aim of this thesis is to find the mechanical properties of a non-homogeneous material in the hypothesis of elastic behaviour. To overcome the problems of conventional testing, in which the macroscopic properties are determined, and identify the real Poisson’ s ratio of a material, the spatial distribution of dis-placements has been measured. To obtain, what is called, a displacement field, Digital Image Correlation (DVC), is used. Thanks to the DVC it has been possible to obtain displacement field measurements from a 3D image series (from initial to deformed), results of a test.The 3D images treated in this thesis are either synthetically generated, or as a result of x-ray tomography on a real experiment.In both cases the initial configuration of the specimens has been chosen with increasingly complicated morphologies.