Unit/metric of "world camera coordinate system"?

[qisun0]

I am trying to run a gaze tracking through a non-screen device, which means I have to calibrate pupil using manual pattern calibration.

In my experiments, my calibration worked because the pupil player shows correct result. However, in my program, the need is to obtain the relative gaze xyz (in the 3D scene space) position in each frame compared with the first frame's gaze point. I noticed there is a "gaze_point_3d" position, which is "position of the 3d gaze point (the point the subject looks at) in the world camera coordinate system". Is this the data I should use? I tried that already assuming the unit is mm, but the result was unexpected. Is it because I misunderstood this variable or its metric/unit? Or I actually used the wrong variable?

[papr]

Dear @qisun0, please excuse the long response time.

You are correct with your assumption that unit of the gaze_point_3d is mm. The origin of this coordinate system is the optical center of the scene camera.

[qisun0]

Sorry for the late reply.

Thanks for the help. I used surface tracking and it worked.

On Thu, Jan 12, 2017 at 4:42 AM, Pablo Prietz notifications@github.com wrote:

Dear @qisun0 https://github.com/qisun0, please excuse the long response time.

You are correct with your assumption that unit of the gaze_point_3d is mm. The origin of this coordinate system is the optical center of the scene camera.

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub https://github.com/pupil-labs/pupil/issues/567#issuecomment-272118229, or mute the thread https://github.com/notifications/unsubscribe-auth/ATGhOAAKmHNqaV8CBdGy60M3M9pioVszks5rRfV6gaJpZM4LXWpb .

-- Qi Sun PhD Student, Department of Computer Science, Stony Brook University, Stony Brook, NY 11790