This application is another example of what can be done with machine vision. It uses the tools from FSI Automation XCaliper.
First it locates all objects and then moves the search tool to each object to analyse it. Also notice that
the objects can be anywhere in a large area and can be at any orientation, as shown below !
If the program can't find any match to a known animal, the 'unkown animal' message is displayed. Also
the message or another signal can be sent out via RS-232 hard wire, or whatever is necessary.
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Animal Crackers: a case study in Pattern Recognition
This is a demo of Blob tools and Pattern Recognition. Pattern recognition is used in
many applications: sorting items, identifying items, finding specific
locations on parts for example the registration marks on printed
materials or the fiducial points on a printed circuit board. Pattern
Matching is used in making Optical Character Recognition applications (OCR).
Pattern Matching can be programmed using a variety of techniques
including neural nets and gray scale correlation. Most machine vision
software packages have a pattern recognition function or add-on module.
The user, systems integrator of machine vision systems teaches the
System what pattern to look for and what to call the pattern.
Typically, the system has to be shown examples of the pattern and
examples of what the pattern is not. In this example, we've taught the
System what each different animal cracker looks like: elephant, donkey,
cat, etc. In some systems, the system will automatically identify the
pattern regardless of rotation. In others the user has to teach the
system the various angles, or the system has to teach itself what the
pattern looks like at the various angles, both of which require the
System to search for multiple patterns which takes processing time
during use, or the System has to rotate the image or pattern during
run-time which also slows down processing. To speed up processing this
application uses a blob tool to first locate items of sufficient size.
Then it searches only at the location of the blob and rotates just
there. The system outputs the identification, location, and rotation of
each object. Objects which are unidentifiable are defects.
Applications could include sorting, pick and place, and identification
to ensure that the correct part is being used in an assembly.
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