Given that LibVLCSharp is fully opensource, I encourage you to have a look at the code whenever you have questions.
Aspect ratio management is provided as a feature of the MediaPlayerElement
component, but you can easily retrieve and use that code if you are not using that component.
private void UpdateAspectRatio(AspectRatio? aspectRatio = null)
{
var mediaPlayer = MediaPlayer;
var videoView = VideoView;
if (aspectRatio == null)
{
aspectRatio = GetAspectRatio(mediaPlayer);
}
if (videoView != null && mediaPlayer != null)
{
switch (aspectRatio)
{
case AspectRatio.Original:
mediaPlayer.AspectRatio = null;
mediaPlayer.Scale = 1;
break;
case AspectRatio.Fill:
var videoTrack = GetVideoTrack(mediaPlayer);
if (videoTrack == null)
{
break;
}
mediaPlayer.Scale = 0;
mediaPlayer.AspectRatio = IsVideoSwapped((VideoTrack)videoTrack) ? $"{videoView.Height}:{videoView.Width}" :
$"{videoView.Width}:{videoView.Height}";
break;
case AspectRatio.BestFit:
mediaPlayer.AspectRatio = null;
mediaPlayer.Scale = 0;
break;
case AspectRatio.FitScreen:
videoTrack = GetVideoTrack(mediaPlayer);
if (videoTrack == null)
{
break;
}
var track = (VideoTrack)videoTrack;
var videoSwapped = IsVideoSwapped(track);
var videoWidth = videoSwapped ? track.Height : track.Width;
var videoHeigth = videoSwapped ? track.Width : track.Height;
if (track.SarNum != track.SarDen)
{
videoWidth = videoWidth * track.SarNum / track.SarDen;
}
var ar = videoWidth / (double)videoHeigth;
var videoViewWidth = videoView.Width;
var videoViewHeight = videoView.Height;
var dar = videoViewWidth / videoViewHeight;
var rawPixelsPerViewPixel = DisplayInformation.ScalingFactor;
var displayWidth = videoViewWidth * rawPixelsPerViewPixel;
var displayHeight = videoViewHeight * rawPixelsPerViewPixel;
mediaPlayer.Scale = (float)(dar >= ar ? (displayWidth / videoWidth) : (displayHeight / videoHeigth));
mediaPlayer.AspectRatio = null;
break;
case AspectRatio._16_9:
mediaPlayer.AspectRatio = "16:9";
mediaPlayer.Scale = 0;
break;
case AspectRatio._4_3:
mediaPlayer.AspectRatio = "4:3";
mediaPlayer.Scale = 0;
break;
}
}
if (_aspectRatio != aspectRatio)
{
_aspectRatio = (AspectRatio)aspectRatio;
AspectRatioChanged?.Invoke(this, EventArgs.Empty);
}
}
See here https://code.videolan.org/videolan/LibVLCSharp/blob/3.x/LibVLCSharp/Shared/MediaPlayerElement/AspectRatioManager.cs
Do note that both the AspectRatio
and Scale
properties need to be updated when changing aspect ratio, as they are intertwined.
I'd like to know if I can open the video in another view in fullscreen mode when tapping the button, just like youtube does.
I'm not sure what you mean by this. If you refer to navigation, see my blogpost about it.