Ghost tag detection

[manan-peppermint]

Describe the bug The AprilTag detection code correctly identifies tags in images, but it randomly and frequently detects tag IDs on the ground or on various objects, even when no tags are present at those locations.

To Reproduce Steps to reproduce the behavior:

Run the opencv_demo from the examples folder with provided images. Observe the detection results for instances where non-existent tags are identified.

Expected behavior No ghost tags should be detected; the algorithm should only identify actual tags present in the images.

Input Image

Screenshots

Operating Sytem Ubuntu 22.04

Installation Method I built AprilTag from source following the instructions in the README.

Code version Current GitHub HEAD

Additional context To troubleshoot the issue, I initially used a static image and tuned the parameters to minimize faulty tag detection. This approach worked with other images captured simultaneously. However, upon deploying the detection on fresh images, the issue of detecting ghost tags reappeared. Despite using the same commit from the AprilTag main branch, the problem persists.