How to: Record Video in a Camera Application for Windows Phone

// Update the buttons and text on the UI thread based on app state.
private void UpdateUI(ButtonState currentButtonState, string statusMessage)
{
    // Run code on the UI thread.
    Dispatcher.BeginInvoke(delegate
    {

        switch (currentButtonState)
        {
            // When the camera is not supported by the device.
            case ButtonState.CameraNotSupported:
                StartRecording.IsEnabled = false;
                StopPlaybackRecording.IsEnabled = false;
                StartPlayback.IsEnabled = false;
                PausePlayback.IsEnabled = false;
                break;

            // First launch of the application, so no video is available.
            case ButtonState.Initialized:
                StartRecording.IsEnabled = true;
                StopPlaybackRecording.IsEnabled = false;
                StartPlayback.IsEnabled = false;
                PausePlayback.IsEnabled = false;
                break;

            // Ready to record, so video is available for viewing.
            case ButtonState.Ready:
                StartRecording.IsEnabled = true;
                StopPlaybackRecording.IsEnabled = false;
                StartPlayback.IsEnabled = true;
                PausePlayback.IsEnabled = false;
                break;

            // Video recording is in progress.
            case ButtonState.Recording:
                StartRecording.IsEnabled = false;
                StopPlaybackRecording.IsEnabled = true;
                StartPlayback.IsEnabled = false;
                PausePlayback.IsEnabled = false;
                break;

            // Video playback is in progress.
            case ButtonState.Playback:
                StartRecording.IsEnabled = false;
                StopPlaybackRecording.IsEnabled = true;
                StartPlayback.IsEnabled = false;
                PausePlayback.IsEnabled = true;
                break;

            // Video playback has been paused.
            case ButtonState.Paused:
                StartRecording.IsEnabled = false;
                StopPlaybackRecording.IsEnabled = true;
                StartPlayback.IsEnabled = true;
                PausePlayback.IsEnabled = false;
                break;

            default:
                break;
        }

        // Display a message.
        txtDebug.Text = statusMessage;

        // Note the current application state.
        currentAppState = currentButtonState;
    });
}

public void InitializeVideoRecorder()
{
    if (captureSource == null)
    {
        // Create the VideoRecorder objects.
        captureSource = new CaptureSource();
        fileSink = new FileSink();

        videoCaptureDevice = CaptureDeviceConfiguration.GetDefaultVideoCaptureDevice();

        // Add eventhandlers for captureSource.
        captureSource.CaptureFailed += new EventHandler<ExceptionRoutedEventArgs>(OnCaptureFailed);

        // Initialize the camera if it exists on the device.
        if (videoCaptureDevice != null)
        {
            // Create the VideoBrush for the viewfinder.
            videoRecorderBrush = new VideoBrush();
            videoRecorderBrush.SetSource(captureSource);

            // Display the viewfinder image on the rectangle.
            viewfinderRectangle.Fill = videoRecorderBrush;

            // Start video capture and display it on the viewfinder.
            captureSource.Start();

            // Set the button state and the message.
            UpdateUI(ButtonState.Initialized, "Tap record to start recording...");
        }
        else
        {
            // Disable buttons when the camera is not supported by the device.
            UpdateUI(ButtonState.CameraNotSupported, "A camera is not supported on this device.");
        }
    }
}

// Set recording state: start recording.
private void StartVideoRecording()
{
    try
    {
        // Connect fileSink to captureSource.
        if (captureSource.VideoCaptureDevice != null
            && captureSource.State == CaptureState.Started)
        {
            captureSource.Stop();

            // Connect the input and output of fileSink.
            fileSink.CaptureSource = captureSource;
            fileSink.IsolatedStorageFileName = isoVideoFileName;
        }

        // Begin recording.
        if (captureSource.VideoCaptureDevice != null
            && captureSource.State == CaptureState.Stopped)
        {
            captureSource.Start();
        }

        // Set the button states and the message.
        UpdateUI(ButtonState.Recording, "Recording...");
    }

    // If recording fails, display an error.
    catch (Exception e)
    {
        this.Dispatcher.BeginInvoke(delegate()
        {
            txtDebug.Text = "ERROR: " + e.Message.ToString();
        });
    }
}

// Set the recording state: stop recording.
private void StopVideoRecording()
{
    try
    {
        // Stop recording.
        if (captureSource.VideoCaptureDevice != null
        && captureSource.State == CaptureState.Started)
        {
            captureSource.Stop();

            // Disconnect fileSink.
            fileSink.CaptureSource = null;
            fileSink.IsolatedStorageFileName = null;

            // Set the button states and the message.
            UpdateUI(ButtonState.NoChange, "Preparing viewfinder...");

            StartVideoPreview();
        }
    }
    // If stop fails, display an error.
    catch (Exception e)
    {
        this.Dispatcher.BeginInvoke(delegate()
        {
            txtDebug.Text = "ERROR: " + e.Message.ToString();
        });
    }
}

// Set the recording state: display the video on the viewfinder.
private void StartVideoPreview()
{
    try
    {
        // Display the video on the viewfinder.
        if (captureSource.VideoCaptureDevice != null
        && captureSource.State == CaptureState.Stopped)
        {
            // Add captureSource to videoBrush.
            videoRecorderBrush.SetSource(captureSource);

            // Add videoBrush to the visual tree.
            viewfinderRectangle.Fill = videoRecorderBrush;

            captureSource.Start();

            // Set the button states and the message.
            UpdateUI(ButtonState.Ready, "Ready to record.");
        }
    }
    // If preview fails, display an error.
    catch (Exception e)
    {
        this.Dispatcher.BeginInvoke(delegate()
        {
            txtDebug.Text = "ERROR: " + e.Message.ToString();
        });
    }
}

// Start the video recording.
private void StartRecording_Click(object sender, EventArgs e)
{
    // Avoid duplicate taps.
    StartRecording.IsEnabled = false;

    StartVideoRecording();
}

// Handle stop requests.
private void StopPlaybackRecording_Click(object sender, EventArgs e)
{
    // Avoid duplicate taps.
    StopPlaybackRecording.IsEnabled = false;

    // Stop during video recording.
    if (currentAppState == ButtonState.Recording)
    {
        StopVideoRecording();

        // Set the button state and the message.
        UpdateUI(ButtonState.NoChange, "Recording stopped.");
    }

    // Stop during video playback.
    else
    {
        // Remove playback objects.
        DisposeVideoPlayer();

        StartVideoPreview();

        // Set the button state and the message.
        UpdateUI(ButtonState.NoChange, "Playback stopped.");
    }
}

// Start video playback.
private void StartPlayback_Click(object sender, EventArgs e)
{
    // Avoid duplicate taps.
    StartPlayback.IsEnabled = false;

    // Start video playback when the file stream exists.
    if (isoVideoFile != null)
    {
        VideoPlayer.Play();
    }
    // Start the video for the first time.
    else
    {
        // Stop the capture source.
        captureSource.Stop();

        // Remove VideoBrush from the tree.
        viewfinderRectangle.Fill = null;

        // Create the file stream and attach it to the MediaElement.
        isoVideoFile = new IsolatedStorageFileStream(isoVideoFileName,
                                FileMode.Open, FileAccess.Read,
                                IsolatedStorageFile.GetUserStoreForApplication());

        VideoPlayer.SetSource(isoVideoFile);

        // Add an event handler for the end of playback.
        VideoPlayer.MediaEnded += new RoutedEventHandler(VideoPlayerMediaEnded);

        // Start video playback.
        VideoPlayer.Play();
    }

    // Set the button state and the message.
    UpdateUI(ButtonState.Playback, "Playback started.");
}

// Pause video playback.
private void PausePlayback_Click(object sender, EventArgs e)
{
    // Avoid duplicate taps.
    PausePlayback.IsEnabled = false;

    // If mediaElement exists, pause playback.
    if (VideoPlayer != null)
    {
        VideoPlayer.Pause();
    }

    // Set the button state and the message.
    UpdateUI(ButtonState.Paused, "Playback paused.");
}

private void DisposeVideoPlayer()
{
    if (VideoPlayer != null)
    {
        // Stop the VideoPlayer MediaElement.
        VideoPlayer.Stop();

        // Remove playback objects.
        VideoPlayer.Source = null;
        isoVideoFile = null;

        // Remove the event handler.
        VideoPlayer.MediaEnded -= VideoPlayerMediaEnded;
    }
}

private void DisposeVideoRecorder()
{
    if (captureSource != null)
    {
        // Stop captureSource if it is running.
        if (captureSource.VideoCaptureDevice != null
            && captureSource.State == CaptureState.Started)
        {
            captureSource.Stop();
        }

        // Remove the event handler for captureSource.
        captureSource.CaptureFailed -= OnCaptureFailed;

        // Remove the video recording objects.
        captureSource = null;
        videoCaptureDevice = null;
        fileSink = null;
        videoRecorderBrush = null;
    }
}