Rockwell Automation 5370-CVIM2 Module - Manual (Page 339)

5 Chapter Chapter 7
Inspection Tools
7–101
The feature finder tool is intended to perform object counting and object
identification on the basis of gray scale template matching. Here are two of
the inspection functions that it can perform:
•
Count objects in the image when a window using the binary–based object
counting operation cannot be used for any reason.
•
Identify one object in the image on the basis of template matching.
Configuring a feature finder tool is nearly identical to configuring a reference
window tool. Thus, this section concentrates on the information that is
unique to the feature finder tool. For the remaining information, refer to the
Reference Window Tool section in Chapter 6, Reference Tools.
Feature Finder Tool: Basic Elements
A feature finder tool consists of a number of basic elements, which are
described briefly as follows:
Feature finder tool –– This term refers to the whole feature finder tool; that
is, each instance of “
F. Finder ” in the toolset edit panel.
Feature window –– This window defines a small portion of the image that
contains a unique workpiece feature. The “feature image” is stored in
memory during configuration, and it is the “template” that the feature finder
tool uses when it searches for a matching feature on a workpiece.
Search window –– This window defines the portion of the image within
which the smaller feature window searches for a particular workpiece feature.
Here is how a feature finder tool works during inspection operations: The
feature window, using a stored feature image as a template, searches the
search window for a region that matches (or nearly matches) the stored
template. When it finds a matching region, the “feature window” adds one to
the feature count. It repeats this counting process for each object within the
search window that matches the stored template.
The user can set range limits according to the number of features that the
inspection application is expected to find.
Feature Finder Tool Edit Panel
Once you have added a feature finder tool to the toolset edit panel, you can
configure it for an inspection application by picking the
F. Finder field in the
panel. When you do, the feature finder tool edit panel appears, as shown by
the example in Figure 7.85 (page 7–102).
Feature Finder Tool