Human detection

Hi,
I’m a art student in france, and for a project i need to detect human and their distance from one object.
I have a external camera filming on the scene and exporting it in touch designer.
I tried with blob tracking and motion detector but its not clear enough yet.
My choice is now on using opencv with a script top, but my knowledge about python and especially python in touch designer is not enough to make this work.
Am i on the good way of doing this ? And if yes how can i make this work ? Or no and which way i should use
Thanks