An Introduction to the Kinect Sensor

Recognizing People with Kinect

One very popular use for the Kinect sensor is recognizing and tracking people standing in front of it. The Kinect sensor itself does not recognize people; it simply sends the depth image to the host device, such as an Xbox or computer. Software running on the host device contains logic to decode the information and recognize elements in the image with characteristic human shapes. The software has been “trained” with a wide variety of body shapes. It uses the alignment of the various body parts, along with the way that they move, to identify and track them.

Figure 1-9 shows the output produced by the body-tracking software as a “stick figure” with lines joining the various elements.

Figure 1-9 Skeleton information retrieved using the Kinect software.

The Kinect software can also recognize the height and proportions of a particular person. For example, this feature lets Xbox Live users “train” their Xbox so it recognizes them when they walk into a room.