Community Research and Development Information Service - CORDIS


This thesis presents an original processing chain for automatic spatial and thematic generalization of satellite-derived products for introduction in a Geographic Information system.
The generalization process works on independent image-objects formed by a closed boundary and a corresponding enclosed-region on the classified image . Initial image-objects are obtained by integrating the classified image with a geographically corresponding satellite derived edge segmented image.
The generalization process is organized in two main levels of abstraction. Firstly Geometric generalization , responsible for the spatial and thematic simplification of the classified image, elaborating the initial image objects in to higher level polygons ( the spatial basis of the final product).
Secondly Semantic generalization, responsible for the thematic conversion of the simplified product, associating each higher level polygon to the most appropriate land use class.
The CORINE land cover classification scheme was taken as the target product during this thesis. This classification scheme is however overly detailed for direct comparison with satellite-derived products. To overcome this an intermediate classification was defined in this thesis: Pseudo CORINE (pcor), which is a 1-level scheme containing: bottom-level CORINE classes which are automatically recognizable by image processing techniques, and 2nd level CORINE classes as substitutes for those CORINE classes not automatically recognizable.
The definition of the Pcor scheme allowed an automatic nomenclature conversion, organized in two steps: 1)re-labelling, based on syntax matching, of low-level classes presenting a one -to -one relationship with a single Pcor class 2) contextual reasoning, based on mutually exclusive hierarchical rules, for the conversion of low-level classes which present a one-to-many relationship with pcor classes.
A fully automatic generalization process has been developed and verified during this

Additional information

Authors: GOFFREDO S,
Bibliographic Reference: EUR 18127 EN (1998) 236pp.
Availability: Available from CCR Ispra - Servizio Pubblicazioni
Record Number: 199910545 / Last updated on: 1999-04-01
Original language: en
Available languages: en