Microsoft has launched the Kinect SDK beta, giving Windows developers an official way to use the Xbox's sensor-packed Kinect accessory.

To launch the SDK, Microsoft held a special 24-hour coding event at its Redmond headquarters. The company invited around 40 developers and researchers, including Joshua Blake, founder of the OpenKinect Project to develop open source drivers for the hardware, to spend 24 hours developing new Kinect software. Though interrupted by a power outage when an electricity substation blew up nearby, the teams came up with a number of real working programs, including live action Pong, using movement to control the paddles; "Virtual Kinductor"; which lets you conduct an orchestra; and a gesture-driven remote control for a quadrocopter.

Programmatically, the SDK is closely modelled on the equivalent Xbox development kit, modified to ensure that it works on the broader range of PC CPUs and GPUs. Both C++ and managed code are supported. The SDK includes both low-level access to the Kinect's sensors—microphones, video cameras, and the depth sensor—as well as high-level capabilities such as beamforming, to pinpoint the source of a sound, and skeleton tracking. As with the Xbox, Kinect can track the positions of four people, and perform skeleton tracking for two of them.

For all the complexity required to process the raw sensor data, the high-level API itself looks remarkably simple, as a light saber augmented reality application demonstrates.

The beta SDK is only available for noncommercial usage, and the company still isn't saying what its commercial plans will be. That answer likely won't come until later in the year, when the final SDK is released. It may also depend on the kind of applications people develop, and that in turn is influenced by the hardware itself. Even with a Windows SDK, the sensor is ill-suited to conventional desktop applications, as the useful skeleton-tracking facility can only accurately track people at distances of around four to eleven feet. Games are the obvious use, given the Xbox heritage, but Microsoft may take the view that Kinect games should stay on the console.

Microsoft itself seems to have little idea what people will use Kinect for—but in many ways, that's the point. Kinect opens up a range of new human interaction capabilities; now it's time to see what people actually do with them.