The objective of this section is to show you how you
can use the Eigenface method to detect changes on a fixed structure. Before
continuing, we should note that the images that were used for were modified
digitally and not physically. The next step on our research will be to see
how sensitive our algorithm is to physical changes.
First we start by using an image from our training
set. We are going to observe how the maximum distances increases as
imperfections are added.

Maximum
Value = 42542 Minimum Value = 41150
In the next four images we observe at images outside
our training set and how the error increases as imperfections are added.

Maximum
Value = 43020 Minimum Value = 41976

Maximum
Value = 42937 Minimum Value = 41903
The next two images show how small imperfection, on
the right hand side of the building, changes our distances.
One
imperfection was added
Maximum
Value =43032 Minimum Value =42039
Two
imperfections were added

Maximum Value = 43082 Minimum Value = 42098
Even though the difference is small, the changes can
still be noticed. Next we will show how adding imperfections to a known
image can be detected. The original image is not shown but you can see where
the changes have been made (one of the windows was modified).

Maximum
Value = 43172 Minimum Value = 42239
Two windows were modified

Maximum Value = 43175 Minimum Value = 42258
A change on top of the
previous two changes was made
Maximum
Value = 43239 Minimum Value = 42322
Finally the image was considerably altered. Look how
the Euclidean distance increases dramatically.

Maximum
Value = 44227 Minimum Value = 43049
This concludes our results with digitally modified
pictures. The next step is to create an scale model of and observe how well
physical changes can be detected.
See results using physical changes
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Preprocessing Techniques to Improve Recognition