A computer implemented method of processing two-dimensional physical
signals includes five basic components and the associated presentation
techniques of the results. The first component decomposes the
two-dimensional signal into one-dimensional profiles. The second component
is a computer implemented Empirical Mode Decomposition that extracts a
collection of Intrinsic Mode Functions (IMF's) from each profile based on
local extrema and/or curvature extrema. The decomposition is based on the
direct extraction of the energy associated with various intrinsic time
scales in the profiles. In the third component, the IMF's of each profile
are then subjected to a Hilbert Transform. The fourth component collates
the Hilbert transformed IMF's of the profiles to form a two-dimensional
Hilbert Spectrum. A fifth component manipulates the IMF's by, for example,
filtering the two-dimensional signal by reconstructing the two-dimensional
signal from selected IMF(s).