Orientation angle

[Melissande]

Hi,
I work on RealSense D415 camera with Nuitrack. I extract the data from the cameras to process them and I would like to know how can I have the orientation (a float) of each point?

[olga.kuzminykh]

Hi Melissande,

Please advise what do you mean by “the orientation (a float) of each point”?
You can get the orientation of a joint, see more info in our docs.

[Melissande]

I would like to know the rotation of each joint. I wanted to use the Orientation function but this function does not give me a result. This function should get me out the float ?

[olga.kuzminykh]

Using this function, you’ll get the orientation matrix. Please check out this post: Local Joint Coordinate & Rotation Matrix problem

[Melissande]

Thank you for your answer.
I would like to understand what each of the values ​​in the matrix correspond to. Because I don’t understand why for X you use 3 values of this matrix and not only one value.

[olga.kuzminykh]

Local Joint Coordinate & Rotation Matrix problem

In the coordinate system of a depth camera, local X would have coordinates (orient.matrix[0], orient.matrix[3], orient.matrix[6]) , local Y would have coordinates (orient.matrix[1], orient.matrix[4], orient.matrix[7]) , and local Z would have coordinates (orient.matrix[2], orient.matrix[5], orient.matrix[8]) .

As for the question about the T-Pose, please take a look at this video (red vector is X, green is Y, blue is Z): https://www.dropbox.com/s/3boo4tr2a1e7umw/Nuitrack_Joint_Orientation.mp4?dl=0

In Nuitrack SDK, orientation is stored as an orientation matrix. You can transform it to any convenient form, for example, to a quaternion. You can set the rotation with the help of at least 4 values. These are the basics of linear algebra.