Webcam - Camera Preview rotates wrong way

Question

I would like your help please on a WebCamera problem. I've used a library available from Nuget; WebEye.Controls.Wpf.WebCameraControl (version 1.0.0). The URL is https://www.nuget.org/packages/WebEye.Controls.Wpf.WebCameraControl/

The article and instructions are available at: http://www.codeproject.com/Articles/330177/Yet-another-Web-Camera-control

Due to project constraints, I developed a WPF application for a Linx tablet (Windows 10), rather than as a Universal Windows Application. I used the WebEye library to connect to the webcam on the tablet and take pictures with it. It works fine when I hold the tablet in landscape, but not when I hold the tablet in portrait mode. In portrait mode, the CameraPreview/VideoWindow automatically rotates -90 degrees.

I tried resolve the problem to no avail.

• Rotate the control surrounding the video window via the Webcamera RenderTransform or LayoutTransform property – The control rotates but the video image does not rotate correctly.
• Tried to rotate the VideoWindow inside the WebCamera Content property - I got the source code from the GitHub and set the VideoWindow available for access. Recompled the library and used it to rotate the VideoWindow via its RenderTransform property. https://github.com/jacobbo/WebEye/tree/master/WebCameraControl

No matter what I do, the camera preview is always -90 degrees.

The library is simple and it does not have many properties to manipulate the video window.

The webcontrol is in XAML.

<wpf:WebCameraControl x:Name="webCameraControl" 
                              MouseDoubleClick="webCameraControl_MouseDoubleClick" 
                              StylusButtonUp="webCameraControl_StylusButtonUp" 
                              MouseUp="webCameraControl_MouseUp" 
                              TouchUp="webCameraControl_TouchUp" 
                              GotMouseCapture="webCameraControl_GotMouseCapture" 
                              />

This is how I initialised the WebCamera. When the UserControl is loaded, it will then automatically connect to the webcam on the tablet. See startViewing() function.

private WebCameraId _cameraID = null;

private void UserControl_Loaded(object sender, RoutedEventArgs e)
        {
            startViewing();
        }

private void startViewing()
        {
            List<WebCameraId> cams = (List<WebCameraId>)webCameraControl.GetVideoCaptureDevices();

            if (cams.Count > 0)
            {
                _cameraID = (WebCameraId)cams[0];

                webCameraControl.StartCapture(_cameraID);
            }
        }

I tried to force the control to rotate it correctly when the app detects a change in the Display screen. See DisplaySettingsChanged event.

public ucWebCam()
{
    InitializeComponent();

    Microsoft.Win32.SystemEvents.DisplaySettingsChanged += SystemEvents_DisplaySettingsChanged;
}

private void SystemEvents_DisplaySettingsChanged(object sender, EventArgs e)
{
    try
    {
        double angle = 0;

        if (SystemParameters.PrimaryScreenWidth > SystemParameters.PrimaryScreenHeight)
        {
            angle = 0;
        }
        else
        {
            angle = -90;
        }

        webCameraControl.StopCapture();

        adjustWebcamAngle(angle);

        webCameraControl.StartCapture(_cameraID);

    }
    catch (Exception ex)
    {

    }
}

private void adjustWebcamAngle(double angle)
{

    try
    {
        // IGNORE portrait boolean flag
        bool portrait = false; 

        if (angle == 90 || angle == 180)
        {
            portrait = true;
        }

        // TRIED TO SET THE ANGLE OF THE CONTROL TO NO AVAIL
        RotateTransform rotTransform = new RotateTransform(angle);
        //rotTransform.Angle = angle;

        ScaleTransform scaleTransform = new ScaleTransform();
        //scaleTransform.ScaleX = (portrait) ? 0 : 1;
        //scaleTransform.ScaleY = (portrait) ? 0 : 1;

        TransformGroup tGroup = new TransformGroup();                
        //tGroup.Children.Add(scaleTransform);
        tGroup.Children.Add(rotTransform);

        // ROTATE CAMERA!
        webCameraControl.RenderTransform = tGroup;

    } catch (Exception ex)
    {

    }
}

So far I only rotated the WebCam control, not the video image.

I looked through the comments in Alexander's article with no joy at: http://www.codeproject.com/Articles/330177/Yet-another-Web-Camera-control

How can I rotate the Camera preview correctly? Can you please advise where I'm going wrong?

I have attached two images to illustrate my problem.

Answer 1

In case you are not a stranger to C#, I would recommend you use the EMGUCV nuget and create your own preview application. It`s not that hard, and you could use MVVM to bind the frames to your View, making it better than using code behind your control.

PS: This is not an answer, but it is a solution to your problem. I cannot not post comments yet, as I do not have 50 points :(

Have a nice day.