So I am trying to use the 3D compute feature in the limelight camera. I am having problems where the x jumps around a lot and it is at a point where it is not usable(the range that it jumps around is like 1 foot). Is it a problem with thresholding? I think that I thresholded it to the best it could be. Has anyone had this problem and how have you fixed/reduced it?
One thing we found is that your physical tape needs to match the model very very closely. For example we made a target by cutting some 4" wide tape in half making 2" wide tape. In a couple of places the cut wasn’t perfectly straight and this confused the tracking. (it makes sense if you think about what the algorithm is doing). You also need very good thresholding. Make sure you’re getting a completely solid threshold image with no flickering around the edges.
Beyond that, there is also the inherent problem which Jared_Russell mentioned: https://github.com/opencv/opencv/issues/8813#issuecomment-359079875. This effect is more problematic when you’re nearly perfectly square to the target. We found that positioning your camera either above or below so that it always has a bit of an angle to the target can help. If your camera is mounted below or above the target height, and angled up or down, then it will always percieve some perspective distortion.