A simple cross-platform desktop GUI app to easily add cover art/thumbnail to MP4 and MKV files.
This app is developed as an Avalonia UI app and uses Taglib# for metadata tag editing, so it should run and work on Windows, Linux, and Mac as well using .NET runtime.
However, it turnes out Avalonia UI currently does not support file drag and drop on Linux ... so it runs fine but it does not accept file drop on Linux... Sad. You have to manually select files using a file open button on Linux.
In order to show video thumbnails/cover pictures in Ubuntu's file manager "Nautilus/GNOME Files", you need to "sudo apt install ffmpegthumbnailer" and configure it to read metadata picture. The config file is loacaed "/usr/share/thumbnailers/ffmpegthumbnailer.thumbnailer" and add -m option to the exec options like this: "Exec=ffmpegthumbnailer -i %i -o %o -s %s -f -m". In windows, MP4's picture is shown normaly but MKV is not supported.
Also, what I learned is that metadata "tags" for movie files in general are pretty messed up. There is no standard at all. This is beyond sad state.
The project file is targeting Avalonia version="11.0.0-preview6" (current).
TODO
