n 
  
SPOT IMAGE 
| Select intrested areas 3] 
Preliminary operation on 2B level 
  
  
  
Raster image in 
UTM Projection 
  
  
  
  
  
  
  
  
  
Classification 
[Theme 1 / [ Theme 2 / eins [Themen | 
Data homogenisation 
  
Y 
Data export into GIS 
Vectorisation 
+ 
  
  
  
  
  
Real world 
  
  
  
  
  
  
  
  
Transformations using 
some GCP 
Figure 2.Integration of SPOT images 
  
  
  
  
The second stage of the integration procedure is the 
image classification. As there are two main natural 
environmental types, each one having an important 
variety (vegetation and water), within the Danube Delta, 
firstly, vegetation information should have been masked 
not to influence water classification. Naturally, the 
Danube Delta aquatic vegetation is prevalent; therefore a 
proper precise separation between the water and 
vegetation plans was rather difficult. The same separator 
operations have been done when 1992 image was used. 
The third stage of the integration procedure is to make 
classification image to be homogeneous (Ducamp,1991). 
During this procedure, the image legibility coefficient 
could be improved after reducing the number of the 
isolated pixels, i.e. polygon reductions after vectorial - 
like operation has taken place. It is quite difficult to get 
807 
the best legible level because a too homogeneous 
information accomplishment entails removals, as well. 
Just an example: a hydrographic grid could lose the 
continuity due to its refinement. A small channel is 
represented on a classified image as a pixel array without 
being always well linked. Applying a "rude" 
homogeneity the channel pixels could be easily lost. 
Such an error could distort some analysing types. On the 
other hand a little homogeneity forth rather many 
isolated pixels. So, the image could not be analysed 
properly and clearly. 
The fourth stage of Remote Sensing information 
integration procedure is to get vector - like classified 
images. 
This operation includes raster - module image change (a 
large storage consumer) into - module one (more 
economic as regards storage). More than that, vector - 
module is more suitable for the complex graphical 
processings and topologic implementations. 
The fifth stage (the last) of integration is overlapping the 
resulted plan over the other ones (information layers). 
The channel hydrographic grid was considered a basis 
and the channel intersection were used as control points 
in this operation. 
4. PRELIMINARY INTERPRETATION OF 
INFORMATION OF THE DATA BASE 
Analysis and Conclusions on the Floating Island 
Dynamics. 
(A) To identify stable elements of the "natural 
patrimony", we have used a proper procedure removing 
dynamic elements/phenomena. Such a phenomenon is 
shown by "floating reed islets" (floating islands) made of 
vegetation and soil sometimes covering almost dozens of 
ha. In their removal, we have used an algebraic 
operation linking the floating reed islets derived from 
1990 and 1992 images, called LAC90 and LAC92. To 
get the new attributes, we have used the following 
commutative rules: 
LAC90 + LAC92 = 900R92 
water90 + water92 = water 
vegetation90 + vegetation92 = vegetation 
vegetation90 + water92 = water 
water90 + vegetation92 = water 
Rule 1 : 
This new plan contains a stable condition of the soil 
cover as against the first classification level. On the other 
hand, if we want to investigate these floating reed islet 
evolutions, a new plan could be set up based on the 
linking operation but using a bit different commutative 
rules: 
Rule2: LAC90 + LAC92 = 90AND92 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996