TV Window using Kinect v2 for windows

I have a kinect camera tracking my head but when I walk closer to the kinect camera it thinks I am getting taller. If I set the pitch to zero then it doesnt happen but it limits how close I can get to the kinect while still being tracked. Also… the x,y coordinate plane is at the same pitch at the kinect. The question is how do I use the pitch of the kinect to calculate the correct height position in space?