Detection of person lying on a surface or against a surface

I have been using Kinect to develop a device. It is trivial to detect people and track the skeleton unless the person is directly against a wall or lying in a bed. Once the person moves 1 cm from the surface the Kinect SDK can detect them. If they are adjacent to a wall or lying in a bed it can’t “find” the person. Is there a setting for the depth of the wall/surface behind the person? Does Nuitrack have a setting for the surface behind the person? Is there a way to set the expected depth of the surface behind the person so it will find the person? My application needs to be able to detect people in a bed or lying on a gurney. How do I set the expected distance to the surface behind the person to zero, so that it will detect the person? Does Nuitrack API have the ability to adjust this distance?


Nuitrack isn’t designed for thresholded depth maps. However you could try the following:

  1. open %NUITRACK_HOME%/data/nuitrack.config file in a text editor;
  2. set “Skeletonization.ActiveUsers” to 1;
  3. add this line:


as the first line to the “Segmentation” section.

Notes about the 3rd step:

  • depth map will be thresholded by height/2 mm (depth values [0…height/2] will be processed only);
  • “beta” parameter is the BoxCutter’s rotation angle in radians along the X-axis of a sensor.

Please note this configuration of the nuitrack.config file isn’t default and could lead to accuracy issues.

Hey Olga,

Is there a document published anywhere that gives details of all the options available in the nuitrack.config.
There seem to be a lot of hidden settings that would possibly of use in our future implementations.




I’m also searching for nuitrack.config docs.

Hi Jassky,

Unfortunately, there is no documentation for nuitrack.config file at the moment as it is not intended to be edited in most cases. It includes internal parameters for modules and experimental features, that’s why it’s likely that backward compatibility for many parameters in this file won’t be supported.

Hi Olga,

I’m currently facing the same problem of trying to track the skeleton of a person who is standing very close to a wall. Does your recommendation to edit the nuitrack.config file still apply or has something changed in the meantime?

Thanks and best regards


Hi Daniel,

Yes, this recommendation is still relevant for your case.

Hi Olga,

thanks for confirming that this recommendation is still valid. I will give it a try.

Best regards