c# - Kinect错误启用流

Question

这是我第一次尝试制作一个使用 Kinect 的程序，我不知道为什么我总是收到 null 错误。也许更了解 KinectSDK 的人可以提供帮助？

public ProjKinect()
{
    InitializeComponent();
    updateSensor(0);//set current sensor as 0 since we just started
}

public void updateSensor(int sensorI)
{
    refreshSensors();//see if any new ones connected
    if (sensorI >= sensors.Length)//if it goes to end, then repeat
    {
        sensorI = 0;
    }
    currentSensorInt = sensorI;
    if (activeSensor != null && activeSensor.IsRunning)
    {
        activeSensor.Stop();//stop so we can cahnge
    }
    MessageBox.Show(sensors.Length + " Kinects Found");
    activeSensor = KinectSensor.KinectSensors[currentSensorInt];
    activeSensor.ColorStream.Enable(ColorImageFormat.RgbResolution640x480Fps30); //ERROR IS RIGHT HERE
    activeSensor.DepthStream.Enable();
    activeSensor.SkeletonStream.Enable();
    activeSensor.SkeletonFrameReady += runtime_SkeletonFrameReady;
    activeSensor.DepthFrameReady += runtime_DepthFrameReady;
    activeSensor.ColorFrameReady += runtime_ImageFrameReady;
    activeSensor.Start();//start the newly enabled one
}
public void refreshSensors()
{
    sensors = KinectSensor.KinectSensors.ToArray();
}

错误:

Object reference not set to an instance of an object.

顺便说一句，它说我连接了 1 个 Kinect，所以我知道它至少识别出我有东西要连接。如果我只说 0 而不是 currentSensorInt，它也不起作用。如果我注释掉 ColorStream.Enable，也会在 DepthStream.Enable 处出错。所以我猜我只是在创建传感器时做错了什么？

希望它是小东西。 提前致谢:)

Answer 1

我没有看到任何明显的错误，但我之前也没有看到传感器以这种方式获取和设置。你看过Kinect for Windows Developer Toolkit吗？例子？有多个关于如何连接到 Kinect 的示例，一些只是暴力连接，而另一些则非常稳健。

例如，这是 SlideshowGestures-WPF 示例中连接代码的精简版:

public partial class MainWindow : Window
{
    /// <summary>
    /// Active Kinect sensor
    /// </summary>
    private KinectSensor sensor;

    /// <summary>
    /// Execute startup tasks
    /// </summary>
    /// <param name="sender">object sending the event</param>
    /// <param name="e">event arguments</param>
    private void WindowLoaded(object sender, RoutedEventArgs e)
    {
        // Look through all sensors and start the first connected one.
        // This requires that a Kinect is connected at the time of app startup.
        // To make your app robust against plug/unplug, 
        // it is recommended to use KinectSensorChooser provided in Microsoft.Kinect.Toolkit
        foreach (var potentialSensor in KinectSensor.KinectSensors)
        {
            if (potentialSensor.Status == KinectStatus.Connected)
            {
                this.sensor = potentialSensor;
                break;
            }
        }

        if (null != this.sensor)
        {
            // Turn on the color stream to receive color frames
            this.sensor.ColorStream.Enable(ColorImageFormat.InfraredResolution640x480Fps30);

            // Add an event handler to be called whenever there is new color frame data
            this.sensor.ColorFrameReady += this.SensorColorFrameReady;

            // Start the sensor!
            try
            {
                this.sensor.Start();
            }
            catch (IOException)
            {
                this.sensor = null;
            }
        }
    }

    /// <summary>
    /// Execute shutdown tasks
    /// </summary>
    /// <param name="sender">object sending the event</param>
    /// <param name="e">event arguments</param>
    private void WindowClosing(object sender, System.ComponentModel.CancelEventArgs e)
    {
        if (null != this.sensor)
        {
            this.sensor.Stop();
        }
    }
}

获取传感器的最简单方法是使用 KinectSensorChooser 类，它是 Microsoft.Kinect.Toolkit 命名空间的一部分。它为您完成所有工作。例如，这是我的设置的修剪版本:

public class MainViewModel : ViewModelBase
{
    private readonly KinectSensorChooser _sensorChooser = new KinectSensorChooser();

    /// <summary>
    /// Initializes a new instance of the MainViewModel class.
    /// </summary>
    public MainViewModel(IDataService dataService)
    {
        if (IsInDesignMode)
        {
            // do something special, only for design mode
        }
        else
        {
            _sensorChooser.Start();

            if (_sensorChooser.Kinect == null)
            {
                MessageBox.Show("Unable to detect an available Kinect Sensor");
                Application.Current.Shutdown();
            }
        }
    }

就是这样。我有一个传感器，可以开始使用它了。我如何连接和控制 Kinect 的更大示例使用工具包中的 KinectSensorManager 类，它位于 KinectWpfViewers 命名空间中:

public class MainViewModel : ViewModelBase
{
    private readonly KinectSensorChooser _sensorChooser = new KinectSensorChooser();

    /// <summary>
    /// Initializes a new instance of the MainViewModel class.
    /// </summary>
    public MainViewModel(IDataService dataService)
    {
        if (IsInDesignMode)
        {
            // do something special, only for design mode
        }
        else
        {
            KinectSensorManager = new KinectSensorManager();
            KinectSensorManager.KinectSensorChanged += OnKinectSensorChanged;

            _sensorChooser.Start();

            if (_sensorChooser.Kinect == null)
            {
                MessageBox.Show("Unable to detect an available Kinect Sensor");
                Application.Current.Shutdown();
            }

            // Bind the KinectSensor from the sensorChooser to the KinectSensor on the KinectSensorManager
            var kinectSensorBinding = new Binding("Kinect") { Source = _sensorChooser };
            BindingOperations.SetBinding(this.KinectSensorManager, KinectSensorManager.KinectSensorProperty, kinectSensorBinding);
        }
    }

    #region Kinect Discovery & Setup

    private void OnKinectSensorChanged(object sender, KinectSensorManagerEventArgs<KinectSensor> args)
    {
        if (null != args.OldValue)
            UninitializeKinectServices(args.OldValue);

        if (null != args.NewValue)
            InitializeKinectServices(KinectSensorManager, args.NewValue);
    }

    /// <summary>
    /// Initialize Kinect based services.
    /// </summary>
    /// <param name="kinectSensorManager"></param>
    /// <param name="sensor"></param>
    private void InitializeKinectServices(KinectSensorManager kinectSensorManager, KinectSensor sensor)
    {
        // configure the color stream
        kinectSensorManager.ColorFormat = ColorImageFormat.RgbResolution640x480Fps30;
        kinectSensorManager.ColorStreamEnabled = true;

        // configure the depth stream
        kinectSensorManager.DepthStreamEnabled = true;

        kinectSensorManager.TransformSmoothParameters =
            new TransformSmoothParameters
            {
                // as the smoothing value is increased responsiveness to the raw data
                // decreases; therefore, increased smoothing leads to increased latency.
                Smoothing = 0.5f,
                // higher value corrects toward the raw data more quickly,
                // a lower value corrects more slowly and appears smoother.
                Correction = 0.5f,
                // number of frames to predict into the future.
                Prediction = 0.5f,
                // determines how aggressively to remove jitter from the raw data.
                JitterRadius = 0.05f,
                // maximum radius (in meters) that filtered positions can deviate from raw data.
                MaxDeviationRadius = 0.04f
            };

        // configure the skeleton stream
        sensor.SkeletonFrameReady += OnSkeletonFrameReady;
        kinectSensorManager.SkeletonStreamEnabled = true;

        // initialize the gesture recognizer
        _gestureController = new GestureController();
        _gestureController.GestureRecognized += OnGestureRecognized;

        kinectSensorManager.KinectSensorEnabled = true;

        if (!kinectSensorManager.KinectSensorAppConflict)
        {
            // set up addition Kinect based services here
            // (e.g., SpeechRecognizer)
        }

        kinectSensorManager.ElevationAngle = Settings.Default.KinectAngle;
    }

    /// <summary>
    /// Uninitialize all Kinect services that were initialized in InitializeKinectServices.
    /// </summary>
    /// <param name="sensor"></param>
    private void UninitializeKinectServices(KinectSensor sensor)
    {
        sensor.SkeletonFrameReady -= this.OnSkeletonFrameReady;
    }

    #endregion Kinect Discovery & Setup

    #region Properties

    public KinectSensorManager KinectSensorManager { get; private set; }

    #endregion Properties
}

所有这些额外代码的优点可以在工具包中的 KinectExplorer 示例中看到。简而言之 - 我可以使用这段代码管理多个 Kinect，拔下一个，程序就会切换到另一个。