UWP VideoView has opaque subtitle background
Summary
LibVLCSharp v3.8.0+ renders subtitles with a semi-transparent background. This behavior is not there in v3.7.0.
Minimal project and steps to reproduce
- Open any video file
- Select an embedded subtitle track using
SetSpu()
, or - Add subtitle file (.srt or .ass) using
AddSlave(MediaSlaveType.Subtitle, uri, true)
What is the current bug behavior?
Subtitle has a semi-transparent, white bounding box background
What is the expected correct behavior?
Subtitle with fully transparent background
Does it work on other plaforms? Does it work with the official VLC apps?
Works on the official VLC app
Works on LibVLCSharp v3.7.0
Relevant LibVLC logs and/or screenshots
Environment
- OS: Win 11
- Version 22H2
- Device: PC
- LibVLC UWP v3.3.1
- LibVLCSharp v3.8.2
Possible fixes
Change AlphaMode in VideoViewBase back to Unspecified.