In this paper, an efficient sampling algorithm for image scanning is propos
ed, suitable to represent "interesting" objects, defined as a set of spatia
lly close measured values that springs out from a background noise (as in a
pplied geophysics in the process of anomaly detection).
This method generates a map of pixels randomly distributed in the plane and
able to cover all the image with a reduced number of points with respect t
o a regular scanning, Simulation results show that a saving factor of about
50% is obtained without information loss, This result can be proved also b
y using a simplified model of the sampling mechanism. The algorithm is able
to detect the presence of an object emerging from a low energy background
and to adapt the sampling interval to the shape of the detected object. In
this way, all of the interesting objects are well represented and can be ad
equately reconstructed, while the roughly sampling in the background produc
es an imperfect reconstruction.
Simulation results show that the method is feasible with good performances
and moderate complexity.