jellyfin/MediaBrowser.MediaEncoding/Subtitles/VttWriter.cs

54 lines
1.9 KiB
C#

using System;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using MediaBrowser.Model.MediaInfo;
namespace MediaBrowser.MediaEncoding.Subtitles
{
/// <summary>
/// Subtitle writer for the WebVTT format.
/// </summary>
public partial class VttWriter : ISubtitleWriter
{
[GeneratedRegex(@"\\n", RegexOptions.IgnoreCase)]
private static partial Regex NewlineEscapeRegex();
/// <inheritdoc />
public void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken)
{
using (var writer = new StreamWriter(stream, Encoding.UTF8, 1024, true))
{
writer.WriteLine("WEBVTT");
writer.WriteLine();
writer.WriteLine("Region: id:subtitle width:80% lines:3 regionanchor:50%,100% viewportanchor:50%,90%");
writer.WriteLine();
foreach (var trackEvent in info.TrackEvents)
{
cancellationToken.ThrowIfCancellationRequested();
var startTime = TimeSpan.FromTicks(trackEvent.StartPositionTicks);
var endTime = TimeSpan.FromTicks(trackEvent.EndPositionTicks);
// make sure the start and end times are different and sequential
if (endTime.TotalMilliseconds <= startTime.TotalMilliseconds)
{
endTime = startTime.Add(TimeSpan.FromMilliseconds(1));
}
writer.WriteLine(@"{0:hh\:mm\:ss\.fff} --> {1:hh\:mm\:ss\.fff} region:subtitle line:90%", startTime, endTime);
var text = trackEvent.Text;
// TODO: Not sure how to handle these
text = NewlineEscapeRegex().Replace(text, " ");
writer.WriteLine(text);
writer.WriteLine();
}
}
}
}
}