= 491 = 
WHAT IS A REMOTELY SENSED TREE? 
A PROPOSAL FOR STRUCTURAL AND 
PSEUDO-SPECTRAL RECONNAISSANCE. 
O 
P. Brambilla 
G.M. Lechi°° 
P. Mussio?? 
The aim of this work is to characterize the typical chroma- 
tic, structural and morphometric performances of the individuals 
of particular vegetal species starting from false colour aerial 
transparencies. 
Neverthless most important aspect of this work is the proposal 
of an automatic reconnaissance methodology of the objects. à 
For this work it was employed a false colour aerial transparen- 
cy 9x9 inches size, 1:10.000 scale: this image was scanned with 
an Optronic Photomation 1700 in the blue, green, red band with 
a scan spot dimension of 50 micron, corresponding on ground at 
50cmx5Ocm pixel size; the three analog electrical signals were 
converted into digital form on the basis of 256 levels. 
Two steps there are in the employed methodology: first a pseudo- 
spectral (rough reconnaissance performed in order to exclude from 
the scene most of the undesired objects, then a characterization 
of the objects from structural point of view. We described now 
the second part, which is performed in three steps: 
a) the description of each individual in the scene and some sim- 
ple relation among them derived from the Fresta Mussio (FM) 
code. The descritpion is performed in terms of elementary to- 
kens (a set of primitive figures) and multivalued operators 
b) the use of the elementary tokens allows the precise defini- 
tion of several convexity and or concavity classes 
c) from the previous criteria there was derived some structural 
coefficient as: boundary complexity, area/perimeter ratio, 
vertices number/perimeter ratio etc. 
Such a combined methodology fournishes a very good results as 
it is described in the paper. 
O no" 
Università di Milano - Facoltà di Fisica 
00 
Istituto per la Geofisica della Litosfera-C.N.R. 
Via Mario Bianco 9 - Milano 
00 ; : ; 
Gruppo Ricerca Scientifica Informatica-Regione Lombardia 
Corso Como 19 - Milano