Definiens Developer 7

Definiens Developer 7 - User Guide
2 Basic Concepts
2.9 Class and Classification
A class is a category of image objects. It can both be used to simply label image objects
or to describe its semantic meaning. Classification is a procedure that associates image
objects with an appropriate class labeled by a name and a color.
Figure 12: Legend window listing classes.
Information contained in image objects is used as a filter for classification. Based on this,
image objects can be analyzed according defined criteria and assigned to classes that
best meet these criteria.
The classes can be grouped in a hierarchical manner, allowing the passing down of their
defining class descriptions to child classes using the inheritance hierarchy. Classes form a
structured network, called class hierarchy.
Figure 13: Sample Class Hierarchy window.
Through the process of classification, each image object is assigned to a certain—or
no—class and thus connected with the class hierarchy. The result of the classification is a
network of classified image objects with concrete attributes, concrete relations to each
other and concrete relations to the classes in the class hierarchy.
2.10 Image Object Hierarchy
During image analysis, multiple image object levels can be created and layered above
the basic pixel level. Two or more image object levels build the image object hierarchy.
Put simply: The image object hierarchy serves as a storage rack for all image objects
levels which represent the different shelves storing the image objects. Thus the image
object hierarchy provides the working environment for the extraction of image
information.
The entirety of image objects is organized into a hierarchical network of image objects.
Such a network is called image object hierarchy. It consists of one or more image object
levels, from fine resolution on the lowest image object level to coarse resolution on the
highest image object level.
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