Tracking Rectangles

[bhasinl]

Looks like a lot of complicated math to work through, but that's to be expected. I am interested in how your first link does perspective rectangle detection, but it doesn't seem to include any mathematical descriptions. There are some vague mentions of finding the vanishing points and the unit vector field pointing in the direction of vanishing lines, but nothing specific.

There's currently a rectangle processing VI or something like that for LabView programers. I'm hoping that could be ported to Java (and/or C++) soon, since we moved on from LabView a long while back. Is there any word on this?

I was also wondering how other teams accomplished tracking of retro-reflective tape (in circular and rectangular shapes) for Logomotion in Java. From an electronic point of view, a cluster of LEDs around the camera seems necessary. However, programmatically, was it necessary to do Hough Transforms? If so, is there a more concise description of these transforms we can access? Perhaps how to take the transformed image and use it to determine the edges of a rectangle? Thanks as always.