6

Which is the best visual fiducial marker (2D barcode) for detection and robust and accurate pose estimation?

Im not looking for a fiducial marker which can store lot of information. The main goal is just to get the pose of the marker with respect to the camera as accurate as possible.

vacky
  • 417
  • 4
  • 11
  • 1
    How do you define best? What are your criteria? What have you found and what issues do you see with them? – Shahbaz Jun 21 '17 at 19:21
  • @Shahbaz Best in terms of how accurate it is to estimate the pose of the marker – vacky Jun 21 '17 at 19:23
  • @Shahbaz I have looked into QR Codes and April tags. But I realized that there are other markers as well like Chili tags. So I want to know which of these markers is best for pose estimation – vacky Jun 21 '17 at 19:26

1 Answers1

6

AprilTag is the state-of-the-art solution for pose estimation. The library itself already has pre-built functions to compute the marker position, given its size. The pose is estimated by homography decomposition and it's quite good if you don't go too far (2 or 3 meters for a 20cm marker). There is the C implementation made by the authors at University of Michigan (now AprilTag 2, look here) or you can go with the MIT C++ implementation of the original algorithm, here.

There are many kind of fiducial markers anyway, and it is very difficult to tell which should be the best for you. For a recent project in which I had to estimate the marker poses from a monocular camera mounted on a quadcopter I made a modified version of the AprilTag adding circles around the marker to improve pose stability. Also, I preferred to compute the pose using the Perspective-N-Point method, by using the solvePnP function included in OpenCV.

I see now this nice novelty, STag: you could also give it a try... seems promising, never used though, is really new (July 2017)

valleymanbs
  • 161
  • 1
  • 4
  • could you tell me more details about your tracking of an apriltag through a camera mounted on a quadrotor? – desmond13 Feb 21 '18 at 10:31
  • 1
    It’s a quite broad question... there are some aspects I cannot discuss, since I signed a non disclosure agreement. If you have any specific question feel free to ask and I’ll see if and how I can give you an answer! Good luck anyway – valleymanbs Feb 22 '18 at 16:18
  • sorry for the delay. The main question for me is: what camera are you using on the drone to detect the apriltag? It would be nice if you could contact me through email. I have the link to my website in my profile. Thanks. – desmond13 Mar 07 '18 at 16:24