qian256 / HoloLensARToolKit

Marker tracking using the front-facing camera of HoloLens (both 1 and 2) and Unity, with a wrapper of ARToolKit built for UWP (Windows Universal Platform)
GNU Lesser General Public License v3.0
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Is HoloLensCamCalib enough to calibrate and align the HL2? Do we also need to do display calibration using 20 alignment described in the paper? #64

Open nocardio opened 3 years ago

nocardio commented 3 years ago

Hi all,

I am trying to follow the instruction in this github repository to calibrate and align the object in HoloLens 2. As I read the codes, I am getting confused with the correct procedures to calibrate and correct alignment in HL2.

In this paper , it was mentioned that we need to align the 5 corners of the real cube with their corresponding virtual counterparts in the scene (a total of 20 corners) and then applied DLT to compute the corresponding transformations. However, in this repository and the scripts implementation, I only found the calibration using the 7x5 chessboard and these descriptions: "When the virtual content is not registered well, you shoud consider: Calibrate your HoloLens camera, following HoloLensCamCalib repository, then point to the customized calibration file in ARUWP Controller / Camera Param Filename. Set the offset matrix in ARUWPMarker::calibrationMatrix. The Matrix4x4 will be automatically left-multiplied to whatever tracking results. For example, if you want to change the position of the virtual content, you can modify the last column of the calibration matrix."

Everyone, please enlighten me. Should I just calculate the calibration using the checkerboard and then adjust the last column of the calibration matrix? Or, Should I perform cube alignment using the described procedures in the paper after calibrated the front-facing camera using the checkerboard? If so, how and which transformation matrix should I use for the next development for AR tracking in HL2?

Thank you very much and I really appreciate anyone responds/feedbacks.