LibVLCSharp - ignores preferred-quality setting (Youtube)

I have asked this on the forums and the suggestion was that I should log this as a bug as the issue happens in both the vlc windows desktop client, as well as in my libvlcsharp winforms application.

I cannot get LibVLCSharp to display youtube streams with a lower preferred quality.

I init LibVLC like so: LibVLC _libVLC = new LibVLC("--preferred-resolution=240");

and then use the VideoView control to display the stream.

The URL that I've test with: https://www.youtube.com/watch?v=FbVennP7Sqw&t=3308s

The video does have a lower option as I can set it to 240 in the browser and it works. Inside the VLC desktop client, it also seems to ignore the preferred quality setting under Preferences -> Input/Codecs?

Is it a luac issue? I have updated both my youtube.lua and youtube.luac inside my libvlc folder from this url: https://github.com/videolan/vlc-3.0/blo ... outube.lua

It is a blocking issue as I need to be able to show the lower quality stream to use the least amount of bandwidth.

Hello, and thanks for your patronage,

This is a duplicate of #10237. YouTube offers a wider range of formats, among which 240p as you point out, but only as separate video-only or audio-only tracks: for technical reasons VLC doesn't make use of those, it only makes use of the narrower choice of multiplexed audio+video, ready-to-play streams.

However, when playing the video you linked using --preferred-resolution=240, it does play for me a lower-quality 360p video: it doesn't ignore the setting, and it tries to accomodate your preference with the lowest-resolution audio+video stream available. Can you get it to play the 360p stream too? I'm sorry if 360p is indeed still too much for your use case, but this is not a blocker for us.

If your application can't handle live 360p bandwidth, I can suggest downloading the video beforehand and playing it offline, maybe using a tool such as youtube-dl - it might even support recovering a 240p file. Otherwise if you prefer still using VLC, you could modify the youtube.lua script to get stream information from the adaptiveFormats field instead of the formats field, then - unless you're satisfied with video only - pick both a video and an audio stream URL, and return them both with one as an input-slave option: but this solution might cause reliability issues.

assigned to @linkfanel

added Component::LUA scripts Severity::normal Status::duplicate labels

closed