Display /dev/videoX feed in a GUI on Linux-ARM64

Question

I've got a device running Ubuntu 18.04LTS on a 64-bit ARM processor. I'd like to develop a GUI that will let me access the camera feed of potentially multiple attached devices (/dev/video0, /dev/video1). Ideally this will be possible with a .NET stack (.NET Core and AvaloniaUI are what I'm looking at). I'm aware of using P/Invoke, but only have a rough understanding of using it. I'm also aware of the libv4l2 library, however I'm not sure where to go from there.

If I have to phrase this as a more direct question for SO: How can I display the /dev/videoX feed on an Ubuntu-ARM64 device in a GUI app built with NET Core (ideally with AvaloniaUI)?

Answer 1

1. Install https://www.nuget.org/packages/LibVLCSharp.Avalonia/
2. MainWindow.axaml

<Window xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:vlc="clr-namespace:LibVLCSharp.Avalonia;assembly=LibVLCSharp.Avalonia"
        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
        x:Class="AvaloniaCam.MainWindow"
        Title="AvaloniaCam">
        <vlc:VideoView x:Name="VideoView"/>
</Window>

3. MainWindow.axaml.cs:

    public class MainWindow : Window
    {
        public MainWindow()
        {
            AvaloniaXamlLoader.Load(this);
            if(Design.IsDesignMode)
                return;
            var videoView = this.Get<VideoView>("VideoView");
            var libVlc = new LibVLC();
            videoView.MediaPlayer = new MediaPlayer(libVlc);
            videoView.MediaPlayer.Play(new Media(libVlc, "v4l2://", FromType.FromLocation));
        }
    }

Note that you might need libvlc-dev package installed for P/Invoke layer from libvlcsharp to work.