Kinect® technology uses an infrared (IR) projector in conjunction with two cameras to map a space in three dimensions. The technology is able to recognize human outlines and then extrapolate depth by examining light cast by the IR projector. A wireframe skeleton is assigned to each human outline, which is then used to interpret movements as game inputs. Each Kinect® is capable of recognizing several people at once for the purposes of multiplayer gaming. In addition to this motion sensing Kinect® technology, each device also includes a microphone array that can be used to give vocal commands.
The Kinect® is a motion-sensing video game peripheral device that does not require each player to hold a physical controller. Unlike other camera-based video game peripherals, Kinect® technology is able to accurately sense depth and perform several other functions. The way these devices sense depth is by projecting a semi-random field of infrared light into a room. When the points of light hit an object, the Kinect® technology is able to determine how far away it is by calculating how long it takes the light to reflect back to the device. This allows a depth map to be created that is accurate to within about 1 centimeter (about 0.4 inches).
All of the calculations necessary for creating a depth map are performed by the Kinect® itself. This information is then sent to the game console along with a regular video feed from the traditional camera. Both of these video images are transmitted at 30 frames per second (FPS). The console can then use the depth map to track the position of a person in three dimensions and the regular video feed for facial recognition. Players can teach the system what their faces looks like, after which it is possible for the Kinect® technology to automatically log them in.
In addition to this motion-sensing technology, each Kinect® device also includes a microphone array. The array is composed of four microphones, which makes it possible for the Kinect® technology to recognize the source of each sound in a room. This can be useful for voice commands, since it allows the device to determine which person has spoken. It can also allow the device to differentiate between commands issued by a person and any background noise that originates from a video game or movie that is playing. The microphones can also be used for voice chat and in-game communication, which are features that typically require the use of a headset.