Object tracking data

[muella91]

Hello,

For my VR application I want to track some objects (e.g. a box) and bring them into VR.

1. What is meant by "height" in the object tracking data? The size of the object or the z coordinate?
2. Is the coordinate system in the center of the object or where do the x and y coordinates point to?

   "object_tracks": [{
        "id": 387,
        "object_name": "ball_red",
        "x": -0.89131,
        "y": 2.41851,
        "height": 1.55837,
        "age": 29.471,
        "confidence": 0.0500193
    }]

Thanks!

[nanodust]

Hello Manuel,

The xyz origin is set during extrinsic calibration. One uses the grid to set the zero point on the floor per wiki.

All tracking is then in meters, from that origin.

On Sat, Jan 11, 2020, 5:31 AM Manuel Mueller notifications@github.com wrote:

Hello,

For my VR application I want to track some objects (e.g. a box) and bring them into VR.

1. What is meant by "height" in the object tracking data? The size of the object or the z coordinate?

2. Is the coordinate system in the center of the object or where do the x and y coordinates point to?

   "object_tracks": [{ "id": 387, "object_name": "ball_red", "x": -0.89131, "y": 2.41851, "height": 1.55837, "age": 29.471, "confidence": 0.0500193 }]

Thanks!

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[muella91]

@nanodust Thanks for your answer, but that was not my question. I already did the extrinsic calibration, I know all positions are measured from the OPT world coordinate system. My questions are:

**1. What is meant by "height" in the object tracking data? The size of the object or the z coordinate?

2. Is the coordinate system in the center of the object or where do the x and y coordinates point to?**

I hope the following picture makes my questions clearer.

[jburkeucla]

Height is the z-coordinate. In position and object tracking, the coordinates generally refer to the centroid. (In person tracking, it's more practically the centroid of the upper body, usually.)

[muella91]

@jburkeucla Perfect, thanks for your answer!