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and data management. eCognition Forester is a stand-alone tool
for automatically identifying individual conifer tree crowns from
aerial photographs. Such information is needed by forest managers
to monitor forest resources.

4.6.2 Main Features
eCognition is an icon driven desktop system running on Windows
NT, 2000, and XP. Best performance is achieved on machines with a
minimum of 512 Mb RAM and a Pentium III 500 MHz CPU. Once the
system is activated, a list of functions is displayed at the very top of
the screen (Fig. 4.6). Each of them contains a drag-on menu with more
options displayed if dragged down. Immediately underneath the
toolbar are icons that provide fast access to some commonly used
functions. Image display is accomplished via Definiens Viewer, which
is able to load images, display them, and visualize processed results
in a wide range of formats, including TIF, Graphic Interchange For-
mat (GIF), JPEG, and even the ERDAS Imagine format through a ras-
ter data translator library. Non-technical users may rely on Definiens
Architect to configure and execute versatile image analysis workflows
using a library of analysis actions created in Definiens Developer.
They are then calibrated for the image data being classified using
training samples. It is very similar to Definiens Analyst, which exe-
cutes workflows without requiring preconfiguration or user calibra-
tion before execution. Definiens Developer is a powerful integrated
environment for image analysts to develop and test new analysis
applications. Incorporating all the functionality of Definiens Archi-
tect, Definiens Analyst, and Definiens Viewer, it contains an unparal-
leled array of image, vector, and tabular data import and export func-
tions. Results may be interactively explored and visualized.

4.6.3 Documentation and Evaluation
Definiens supplies a detailed user guide that contains tutorial materi-
als. Contained in the tutorial are a few examples through which the
user can become familiarized with the concept behind object-ori-
ented image analysis and learn how to use the functions of this image
processing system properly to generate the desired results. More user
support, such as a user discussion forum, is needed to provide a means
of communication between Definiens software developers and the
user community, as well as for users to support one another.
Unlike other image analysis packages that have a long history of
existence, eCognition is a recent addition. As a primarily object-ori-
ented image analysis system, it is able to produce more accurate
results than per-pixel-based image classifiers, thanks to the use of
contextual information at multiresolutions. Therefore, it does not
have a comprehensive set of image processing functions, such as 3D
data handling capabilities or tools for analyzing radar data. It also