In writing quite a bit of the code in these posts;

Kinect for Windows SDK V2 Posts

I’d sometimes been trying to take care such that if I had open readers for data ( like body data, infrared data, etc. ) from a KinectSensor and that sensor suddenly became unavailable (e.g. someone unplugged it) then I’d try to make sure I closed the readers and re-opened them when the sensor became available again.

I’d had a nagging feeling all along though that I might be wasting my time and today I thought I’d test that out and this little piece of console code;

namespace ConsoleApplication1
{
  using Microsoft.Kinect;
  using System;

  class Program
  {
    static void Main(string[] args)
    {
      bool readerOpen = false;

      KinectSensor sensor = KinectSensor.GetDefault();
      sensor.Open();

      EventHandler<IsAvailableChangedEventArgs> handler = (s,e) =>
      {
        if (!readerOpen && sensor.IsAvailable)
        {
          readerOpen = true;

          var reader = sensor.ColorFrameSource.OpenReader();

          reader.FrameArrived += (a,b) =>
          {
            Console.WriteLine("frame");
          };
        }
      };

      sensor.IsAvailableChanged += handler;

      handler(null, null);

      Console.ReadLine();
    }
  }
}

seems to suggest that my nagging feeling was right. This code picks up frames from the Kinect sensor whether;

• The sensor is plugged in when the code first runs.
• The sensor is not plugged in when the code first runs.
• The sensor is connected/disconnected while the code is running.

so – as far as I can tell once the code is up and running with an open reader, the underlying bits do the right thing to check whether the sensor has become available/unavailable and to continue to deliver data on that reader whenever they can.

I then wondered whether I could take it even further. What if I attempt to open a reader even if the sensor isn’t available;

namespace ConsoleApplication1
{
  using Microsoft.Kinect;
  using System;

  class Program
  {
    static void Main(string[] args)
    {
      KinectSensor sensor = KinectSensor.GetDefault();
      sensor.Open();

      var reader = sensor.BodyFrameSource.OpenReader();
      reader.FrameArrived += (s, e) =>
        {
          Console.WriteLine("frame");
        };

      Console.ReadLine();
    }
  }
}

and, again, this code works fine whether the sensor is initially available, whether it becomes available later on and whether it goes available/unavailable while running.

That’s a lot of simplification – if only I’d know that before