ECE4580 Homework #11

ECE4580 Homework #11

Problem 1. (25 pts) Fill out the code stubs for findHarrisPts.m and runHarris.m so that runHarris
will work when run and correctly plot the points in the image the pass the Harris corner detector specifications. The
code loads the edges01.mat Matlab file, which contains the campus and TSRB images. Apply the detector to these
images.
For the Harris corner detector, the score to threshold is the product of the eigenvalues minus a fraction of the square
of the sum of the eigenvalues,
score = λ1λ2 − κ(λ1 + λ2)
2 = det(G) − κ (trace(G))2
,
where G is the 2 × 2 matrix from the notes. It is generated from the integral of the matrix [∇I ∇I
T
] over a window of
the image. In the code, I actually request that rather than integrate, you average over the window. Using an averaging
filter normalizes the output to some degree, so that the thresholds don’t vary with the area of the window size.
Turn in your code with one of the edges01.mat images selected. As part of the documentation, turn in one
image with the feature points plotted on it. Explain why you chose this particular image and the parameter settings
that generated the feature points. Also turn in a brief discussion of your experiences applying the corner detector to
the images. What does it find? What does it not find? How well does it match up with your expectations?
Problem 2. (35 pts) Each group has a baby step to perform for the following Thursday. Your are to complete that
baby step and report to the group contact. You should roughly reiterate the baby step, discuss how it was accomplished,
demonstrate through images (if possible) functionality, then briefly note any observations (including cases where it
may not work so faithfully, or what is needed to work very well). If your project involves video and cannot be
demonstrated with still images, then present it to your group contact by Friday (but still turn in everything else with
the homework). This means you should be done by Thursday, but there is a grace period for presenting things should
that be needed. It is up to you and your contact to figure that out.
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