private void Form1_Load(object sender, EventArgs e)
        {
            MediaAttributes attributes = new MediaAttributes(1);
            attributes.Set<Guid>(CaptureDeviceAttributeKeys.SourceType, CaptureDeviceAttributeKeys.SourceTypeVideoCapture.Guid);
            Activate[] activates = MediaFactory.EnumDeviceSources(attributes);
            foreach (var activate in activates)
            {
                string uid = activate.Get(CaptureDeviceAttributeKeys.SourceTypeVidcapSymbolicLink);
                cameraList.Add(uid, activate);
                ComboboxCameraItem item = new ComboboxCameraItem(activate);
                leftCameraCombo.Items.Add(item);
                rightCameraCombo.Items.Add(item);

                if (Properties.Settings.Default.leftCamera == uid)
                {
                    leftCameraCombo.SelectedItem = item;
                }
                if (Properties.Settings.Default.rightCamera == uid)
                {
                    rightCameraCombo.SelectedItem = item;
                }

            }

          // graphicsDeviceManager = new GraphicsDeviceManager(this);
            OVR.Initialize();



            label1.Text = "Init OK";
            hmd = OVR.HmdCreate(0) ?? OVR.HmdCreateDebug(HMDType.DK2);
            if (hmd != null)
            {
                hmd.ConfigureTracking(
                    TrackingCapabilities.Orientation | TrackingCapabilities.Position |
                    TrackingCapabilities.MagYawCorrection, TrackingCapabilities.None);
            }
            else
            {
                label1.Text = "No Oculus connected";
            }
        }
        private void button3_Click(object sender, EventArgs e)
        {
            Activate camera =
                cameraList[
                    ((ComboboxCameraItem) leftCameraCombo.SelectedItem).Value.Get(
                        CaptureDeviceAttributeKeys.SourceTypeVidcapSymbolicLink)];

            IntPtr leftIntPtr;
            //"279a808d-aec7-40c8-9c6b-a6b492c78a66" is MediaSource class GUID
            camera.ActivateObject(System.Guid.Parse("279a808d-aec7-40c8-9c6b-a6b492c78a66"), out leftIntPtr);
            MediaSource source = new MediaSource(leftIntPtr);
            PresentationDescriptor descriptor;
            source.CreatePresentationDescriptor(out descriptor);
            Variant time = new Variant();
            time.ElementType = VariantElementType.UInt; //Is this VT_I8 ??
            time.Value = 0; //Value = 0
            source.BeginGetEvent(leftEyeBeginCallback, this);
            source.Start(descriptor, null, time);
        }