Noob Question

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Jan 15, 2022, 5:22:54 PMJan 15
to BoofCV
I'm pretty new to BoofCV and I was wondering if I'm on the right track with an idea for a project.

I'd like to be able to recognize a singular, unique pattern in a cam-stream and use it as a tracker not unlike a fiducial (the pattern itself is a rectangle in which there's a series of smaller lines) to draw an object over it.

Although a fiducial would be pretty much what I need, I'm looking for a way to either have the fiducial not work on a square image but on a rectangle with rather thin lines and some lines to identify it. Or I was wondering to use blobs or contour lines, though I'm at a loss how to do the recognition and drawing parts in this case.

Does anyone know a solution or a tutorial/example how to do this?

Thanks and all the best,


Jan 15, 2022, 5:36:16 PMJan 15
to BoofCV
P.S.: As you can see, the pattern would be a tattoo and I hope you'll understand why I'd like to avoid the fiducial border at all costs. ;-)


Peter A

Jan 15, 2022, 8:43:24 PMJan 15
to boofcv
Just tried the black polygon detector demo using a local mean threshold and it should be easy to detect the square when up close. You will need to remove false positives and motion blur + detecting from a distance will be an issue. Once you got a candidate rectangle you can try undistorting it using a homography then looking for the inner lines. Won't be trivial to do but shouldn't be too much of a problem to show that it works some of the time.

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