The first alternative is to process the image in order to obtain the contour plot by displaying isolines. Then it can be seen from these images that the lower the density of the sample is, the more changes the image has. This is due to the fact that when the material porosity increases, that makes the ultrasonic waves go through much more reflections. The second alternative is to process signal data in order to evaluate the
material attenuation which is related to the density. The lower the density, the higher the attenuation