Automated Scene Description (ASD)
The exploitation of results provided by Automatic Feature Extraction (AFE) and
Automatic Target Recognition (ATR) algorithms can be greatly facilitated by
analysis of the spatial relationships between the features and/or targets. This
type of analysis can, when appropriate, automatically group objects and targets
to produce higher-level descriptions about the content of any scene. We call
this type of higher-level analysis Automated Scene Description (ASD).
One of the most powerful tools to describe the relative position of one object
to another is the histogram of forces. This quantitative representation of the
relative position between two objects encapsulates structural information about
the objects as well as information about their spatial relationships. It is
sensitive to the shape of the objects, their orientation, their size, and the
distance between them. It lends itself, with great flexibility, to the modeling
of spatial relationships for ASD applications.
Spatial relation models can use the force histograms as input into a fuzzy logic
rule base that then automatically produces linguistic scene descriptions
of the content of an image. The objects in the image/scene can be identified
using AFE and/or ATR methods as appropriate. Spatial rules and meta-rules can
be constructed to group the features/objects together into meaningful
higher-level descriptions. In addition, each linguistic description has a
natural confidence value associated with it. This process is illustrated below.
An example of the combination of ATR algorithms with automated scene description
is shown below. Here, the MSNN ATR algorithm has been used to simultaneously
detect and classify the targets in the scene. The final (maximum confidence)
linguistic description generated by the fuzzy rule system is then output. The
underlined terms surround, convoy, SAM site, etc. are generated
automatically by the linguistic scene methodology.
We are presently conducting research to extend our ASD research to work with AFE
inputs and more complex scenes from high-resolution satellite imagery over
urban areas. In addition, we are pursuing research to develop a methodology to
incorporate other intelligence information (human, signals, etc.) into the ASD
methodology. We are investigating the development of appropriate "intelligence"
meta-rules into the scene understanding rule base.
We believe that a common fuzzy logic framework will allow us to build a natural
ontology for representing this non-image based intelligence. For example, human
intelligence and other intelligence sources often contain fuzzy spatial
descriptions (nearby, in the general vicinity, parked around, etc.) that must
be fused with geospatial data to present a complete intelligence picture.