Port MediaEncoding and Api.Playback from 10e57ce8d21b4516733894075001819f3cd6db6b

13 files changed, 1937 insertions, 0 deletions

diff --git a/MediaBrowser.MediaEncoding/Subtitles/AssParser.cs b/MediaBrowser.MediaEncoding/Subtitles/AssParser.cs
new file mode 100644
index 000000000..71fefba44
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/AssParser.cs
@@ -0,0 +1,122 @@
+using MediaBrowser.Model.Extensions;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Text.RegularExpressions;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class AssParser : ISubtitleParser
+    {
+        private readonly CultureInfo _usCulture = new CultureInfo("en-US");
+
+        public SubtitleTrackInfo Parse(Stream stream, CancellationToken cancellationToken)
+        {
+            var trackInfo = new SubtitleTrackInfo();
+            List<SubtitleTrackEvent> trackEvents = new List<SubtitleTrackEvent>();
+            var eventIndex = 1;
+            using (var reader = new StreamReader(stream))
+            {
+                string line;
+                while (reader.ReadLine() != "[Events]")
+                {}
+                var headers = ParseFieldHeaders(reader.ReadLine());
+
+                while ((line = reader.ReadLine()) != null)
+                {
+                    cancellationToken.ThrowIfCancellationRequested();
+                    
+                    if (string.IsNullOrWhiteSpace(line))
+                    {
+                        continue;
+                    }
+                    if(line.StartsWith("["))
+                        break;
+                    if(string.IsNullOrEmpty(line))
+                        continue;
+                    var subEvent = new SubtitleTrackEvent { Id = eventIndex.ToString(_usCulture) };
+                    eventIndex++;
+                    var sections = line.Substring(10).Split(',');
+
+                    subEvent.StartPositionTicks = GetTicks(sections[headers["Start"]]);
+                    subEvent.EndPositionTicks = GetTicks(sections[headers["End"]]);
+
+                    subEvent.Text = string.Join(",", sections.Skip(headers["Text"]));
+                    RemoteNativeFormatting(subEvent);
+
+                    subEvent.Text = subEvent.Text.Replace("\\n", ParserValues.NewLine, StringComparison.OrdinalIgnoreCase);
+                    
+                    subEvent.Text = Regex.Replace(subEvent.Text, @"\{(\\[\w]+\(?([\w\d]+,?)+\)?)+\}", string.Empty, RegexOptions.IgnoreCase);
+
+                    trackEvents.Add(subEvent);
+                }
+            }
+            trackInfo.TrackEvents = trackEvents.ToArray();
+            return trackInfo;
+        }
+
+        long GetTicks(string time)
+        {
+            TimeSpan span;
+            return TimeSpan.TryParseExact(time, @"h\:mm\:ss\.ff", _usCulture, out span)
+                ? span.Ticks: 0;
+        }
+
+        private Dictionary<string,int> ParseFieldHeaders(string line) {
+            var fields = line.Substring(8).Split(',').Select(x=>x.Trim()).ToList();
+
+            var result = new Dictionary<string, int> {
+                                                         {"Start", fields.IndexOf("Start")},
+                                                         {"End", fields.IndexOf("End")},
+                                                         {"Text", fields.IndexOf("Text")}
+                                                     };
+            return result;
+        }
+
+        /// <summary>
+        /// Credit: https://github.com/SubtitleEdit/subtitleedit/blob/master/src/Logic/SubtitleFormats/AdvancedSubStationAlpha.cs
+        /// </summary>
+        private void RemoteNativeFormatting(SubtitleTrackEvent p)
+        {
+            int indexOfBegin = p.Text.IndexOf('{');
+            string pre = string.Empty;
+            while (indexOfBegin >= 0 && p.Text.IndexOf('}') > indexOfBegin)
+            {
+                string s = p.Text.Substring(indexOfBegin);
+                if (s.StartsWith("{\\an1}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an2}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an3}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an4}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an5}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an6}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an7}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an8}", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an9}", StringComparison.Ordinal))
+                {
+                    pre = s.Substring(0, 6);
+                }
+                else if (s.StartsWith("{\\an1\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an2\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an3\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an4\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an5\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an6\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an7\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an8\\", StringComparison.Ordinal) ||
+                    s.StartsWith("{\\an9\\", StringComparison.Ordinal))
+                {
+                    pre = s.Substring(0, 5) + "}";
+                }
+                int indexOfEnd = p.Text.IndexOf('}');
+                p.Text = p.Text.Remove(indexOfBegin, (indexOfEnd - indexOfBegin) + 1);
+
+                indexOfBegin = p.Text.IndexOf('{');
+            }
+            p.Text = pre + p.Text;
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/ConfigurationExtension.cs b/MediaBrowser.MediaEncoding/Subtitles/ConfigurationExtension.cs
new file mode 100644
index 000000000..973c653a4
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/ConfigurationExtension.cs
@@ -0,0 +1,29 @@
+using System.Collections.Generic;
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Model.Providers;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public static class ConfigurationExtension
+    {
+        public static SubtitleOptions GetSubtitleConfiguration(this IConfigurationManager manager)
+        {
+            return manager.GetConfiguration<SubtitleOptions>("subtitles");
+        }
+    }
+
+    public class SubtitleConfigurationFactory : IConfigurationFactory
+    {
+        public IEnumerable<ConfigurationStore> GetConfigurations()
+        {
+            return new List<ConfigurationStore>
+            {
+                new ConfigurationStore
+                {
+                    Key = "subtitles",
+                    ConfigurationType = typeof (SubtitleOptions)
+                }
+            };
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/ISubtitleParser.cs b/MediaBrowser.MediaEncoding/Subtitles/ISubtitleParser.cs
new file mode 100644
index 000000000..75de81f46
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/ISubtitleParser.cs
@@ -0,0 +1,17 @@
+using System.IO;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public interface ISubtitleParser
+    {
+        /// <summary>
+        /// Parses the specified stream.
+        /// </summary>
+        /// <param name="stream">The stream.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>SubtitleTrackInfo.</returns>
+        SubtitleTrackInfo Parse(Stream stream, CancellationToken cancellationToken);
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/ISubtitleWriter.cs b/MediaBrowser.MediaEncoding/Subtitles/ISubtitleWriter.cs
new file mode 100644
index 000000000..e28da9185
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/ISubtitleWriter.cs
@@ -0,0 +1,20 @@
+using System.IO;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    /// <summary>
+    /// Interface ISubtitleWriter
+    /// </summary>
+    public interface ISubtitleWriter
+    {
+        /// <summary>
+        /// Writes the specified information.
+        /// </summary>
+        /// <param name="info">The information.</param>
+        /// <param name="stream">The stream.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken);
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/JsonWriter.cs b/MediaBrowser.MediaEncoding/Subtitles/JsonWriter.cs
new file mode 100644
index 000000000..474f712f9
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/JsonWriter.cs
@@ -0,0 +1,28 @@
+using MediaBrowser.Model.MediaInfo;
+using MediaBrowser.Model.Serialization;
+using System.IO;
+using System.Text;
+using System.Threading;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class JsonWriter : ISubtitleWriter
+    {
+        private readonly IJsonSerializer _json;
+
+        public JsonWriter(IJsonSerializer json)
+        {
+            _json = json;
+        }
+
+        public void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken)
+        {
+            using (var writer = new StreamWriter(stream, Encoding.UTF8, 1024, true))
+            {
+                var json = _json.SerializeToString(info);
+
+                writer.Write(json);
+            }
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/OpenSubtitleDownloader.cs b/MediaBrowser.MediaEncoding/Subtitles/OpenSubtitleDownloader.cs
new file mode 100644
index 000000000..3954897ca
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/OpenSubtitleDownloader.cs
@@ -0,0 +1,349 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Common.Extensions;
+using MediaBrowser.Common.Net;
+using MediaBrowser.Controller.Configuration;
+using MediaBrowser.Controller.Providers;
+using MediaBrowser.Controller.Security;
+using MediaBrowser.Controller.Subtitles;
+using MediaBrowser.Model.Dto;
+using MediaBrowser.Model.Entities;
+using MediaBrowser.Model.IO;
+using MediaBrowser.Model.Logging;
+using MediaBrowser.Model.Providers;
+using MediaBrowser.Model.Serialization;
+using OpenSubtitlesHandler;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class OpenSubtitleDownloader : ISubtitleProvider, IDisposable
+    {
+        private readonly ILogger _logger;
+        private readonly IHttpClient _httpClient;
+        private readonly CultureInfo _usCulture = new CultureInfo("en-US");
+
+        private readonly IServerConfigurationManager _config;
+        private readonly IEncryptionManager _encryption;
+
+        private readonly IJsonSerializer _json;
+        private readonly IFileSystem _fileSystem;
+
+        public OpenSubtitleDownloader(ILogManager logManager, IHttpClient httpClient, IServerConfigurationManager config, IEncryptionManager encryption, IJsonSerializer json, IFileSystem fileSystem)
+        {
+            _logger = logManager.GetLogger(GetType().Name);
+            _httpClient = httpClient;
+            _config = config;
+            _encryption = encryption;
+            _json = json;
+            _fileSystem = fileSystem;
+
+            _config.NamedConfigurationUpdating += _config_NamedConfigurationUpdating;
+
+            Utilities.HttpClient = httpClient;
+            OpenSubtitles.SetUserAgent("mediabrowser.tv");
+        }
+
+        private const string PasswordHashPrefix = "h:";
+        void _config_NamedConfigurationUpdating(object sender, ConfigurationUpdateEventArgs e)
+        {
+            if (!string.Equals(e.Key, "subtitles", StringComparison.OrdinalIgnoreCase))
+            {
+                return;
+            }
+
+            var options = (SubtitleOptions)e.NewConfiguration;
+
+            if (options != null &&
+                !string.IsNullOrWhiteSpace(options.OpenSubtitlesPasswordHash) &&
+                !options.OpenSubtitlesPasswordHash.StartsWith(PasswordHashPrefix, StringComparison.OrdinalIgnoreCase))
+            {
+                options.OpenSubtitlesPasswordHash = EncryptPassword(options.OpenSubtitlesPasswordHash);
+            }
+        }
+
+        private string EncryptPassword(string password)
+        {
+            return PasswordHashPrefix + _encryption.EncryptString(password);
+        }
+
+        private string DecryptPassword(string password)
+        {
+            if (password == null ||
+                !password.StartsWith(PasswordHashPrefix, StringComparison.OrdinalIgnoreCase))
+            {
+                return string.Empty;
+            }
+
+            return _encryption.DecryptString(password.Substring(2));
+        }
+
+        public string Name
+        {
+            get { return "Open Subtitles"; }
+        }
+
+        private SubtitleOptions GetOptions()
+        {
+            return _config.GetSubtitleConfiguration();
+        }
+
+        public IEnumerable<VideoContentType> SupportedMediaTypes
+        {
+            get
+            {
+                var options = GetOptions();
+
+                if (string.IsNullOrWhiteSpace(options.OpenSubtitlesUsername) ||
+                    string.IsNullOrWhiteSpace(options.OpenSubtitlesPasswordHash))
+                {
+                    return new VideoContentType[] { };
+                }
+
+                return new[] { VideoContentType.Episode, VideoContentType.Movie };
+            }
+        }
+
+        public Task<SubtitleResponse> GetSubtitles(string id, CancellationToken cancellationToken)
+        {
+            return GetSubtitlesInternal(id, GetOptions(), cancellationToken);
+        }
+
+        private DateTime _lastRateLimitException;
+        private async Task<SubtitleResponse> GetSubtitlesInternal(string id,
+            SubtitleOptions options,
+            CancellationToken cancellationToken)
+        {
+            if (string.IsNullOrWhiteSpace(id))
+            {
+                throw new ArgumentNullException("id");
+            }
+
+            var idParts = id.Split(new[] { '-' }, 3);
+
+            var format = idParts[0];
+            var language = idParts[1];
+            var ossId = idParts[2];
+
+            var downloadsList = new[] { int.Parse(ossId, _usCulture) };
+
+            await Login(cancellationToken).ConfigureAwait(false);
+
+            if ((DateTime.UtcNow - _lastRateLimitException).TotalHours < 1)
+            {
+                throw new RateLimitExceededException("OpenSubtitles rate limit reached");
+            }
+
+            var resultDownLoad = await OpenSubtitles.DownloadSubtitlesAsync(downloadsList, cancellationToken).ConfigureAwait(false);
+
+            if ((resultDownLoad.Status ?? string.Empty).IndexOf("407", StringComparison.OrdinalIgnoreCase) != -1)
+            {
+                _lastRateLimitException = DateTime.UtcNow;
+                throw new RateLimitExceededException("OpenSubtitles rate limit reached");
+            }
+
+            if (!(resultDownLoad is MethodResponseSubtitleDownload))
+            {
+                throw new Exception("Invalid response type");
+            }
+
+            var results = ((MethodResponseSubtitleDownload)resultDownLoad).Results;
+
+            _lastRateLimitException = DateTime.MinValue;
+
+            if (results.Count == 0)
+            {
+                var msg = string.Format("Subtitle with Id {0} was not found. Name: {1}. Status: {2}. Message: {3}",
+                    ossId,
+                    resultDownLoad.Name ?? string.Empty,
+                    resultDownLoad.Status ?? string.Empty,
+                    resultDownLoad.Message ?? string.Empty);
+
+                throw new ResourceNotFoundException(msg);
+            }
+
+            var data = Convert.FromBase64String(results.First().Data);
+
+            return new SubtitleResponse
+            {
+                Format = format,
+                Language = language,
+
+                Stream = new MemoryStream(Utilities.Decompress(new MemoryStream(data)))
+            };
+        }
+
+        private DateTime _lastLogin;
+        private async Task Login(CancellationToken cancellationToken)
+        {
+            if ((DateTime.UtcNow - _lastLogin).TotalSeconds < 60)
+            {
+                return;
+            }
+
+            var options = GetOptions();
+
+            var user = options.OpenSubtitlesUsername ?? string.Empty;
+            var password = DecryptPassword(options.OpenSubtitlesPasswordHash);
+
+            var loginResponse = await OpenSubtitles.LogInAsync(user, password, "en", cancellationToken).ConfigureAwait(false);
+
+            if (!(loginResponse is MethodResponseLogIn))
+            {
+                throw new Exception("Authentication to OpenSubtitles failed.");
+            }
+
+            _lastLogin = DateTime.UtcNow;
+        }
+
+        public async Task<IEnumerable<NameIdPair>> GetSupportedLanguages(CancellationToken cancellationToken)
+        {
+            await Login(cancellationToken).ConfigureAwait(false);
+
+            var result = OpenSubtitles.GetSubLanguages("en");
+            if (!(result is MethodResponseGetSubLanguages))
+            {
+                _logger.Error("Invalid response type");
+                return new List<NameIdPair>();
+            }
+
+            var results = ((MethodResponseGetSubLanguages)result).Languages;
+
+            return results.Select(i => new NameIdPair
+            {
+                Name = i.LanguageName,
+                Id = i.SubLanguageID
+            });
+        }
+
+        private string NormalizeLanguage(string language)
+        {
+            // Problem with Greek subtitle download #1349
+            if (string.Equals(language, "gre", StringComparison.OrdinalIgnoreCase))
+            {
+
+                return "ell";
+            }
+
+            return language;
+        }
+
+        public async Task<IEnumerable<RemoteSubtitleInfo>> Search(SubtitleSearchRequest request, CancellationToken cancellationToken)
+        {
+            var imdbIdText = request.GetProviderId(MetadataProviders.Imdb);
+            long imdbId = 0;
+
+            switch (request.ContentType)
+            {
+                case VideoContentType.Episode:
+                    if (!request.IndexNumber.HasValue || !request.ParentIndexNumber.HasValue || string.IsNullOrEmpty(request.SeriesName))
+                    {
+                        _logger.Debug("Episode information missing");
+                        return new List<RemoteSubtitleInfo>();
+                    }
+                    break;
+                case VideoContentType.Movie:
+                    if (string.IsNullOrEmpty(request.Name))
+                    {
+                        _logger.Debug("Movie name missing");
+                        return new List<RemoteSubtitleInfo>();
+                    }
+                    if (string.IsNullOrWhiteSpace(imdbIdText) || !long.TryParse(imdbIdText.TrimStart('t'), NumberStyles.Any, _usCulture, out imdbId))
+                    {
+                        _logger.Debug("Imdb id missing");
+                        return new List<RemoteSubtitleInfo>();
+                    }
+                    break;
+            }
+
+            if (string.IsNullOrEmpty(request.MediaPath))
+            {
+                _logger.Debug("Path Missing");
+                return new List<RemoteSubtitleInfo>();
+            }
+
+            await Login(cancellationToken).ConfigureAwait(false);
+
+            var subLanguageId = NormalizeLanguage(request.Language);
+            string hash;
+
+            using (var fileStream = _fileSystem.OpenRead(request.MediaPath))
+            {
+                hash = Utilities.ComputeHash(fileStream);
+            }
+            var fileInfo = _fileSystem.GetFileInfo(request.MediaPath);
+            var movieByteSize = fileInfo.Length;
+            var searchImdbId = request.ContentType == VideoContentType.Movie ? imdbId.ToString(_usCulture) : "";
+            var subtitleSearchParameters = request.ContentType == VideoContentType.Episode
+                ? new List<SubtitleSearchParameters> {
+                                                         new SubtitleSearchParameters(subLanguageId,
+                                                             query: request.SeriesName,
+                                                             season: request.ParentIndexNumber.Value.ToString(_usCulture),
+                                                             episode: request.IndexNumber.Value.ToString(_usCulture))
+                                                     }
+                : new List<SubtitleSearchParameters> {
+                                                         new SubtitleSearchParameters(subLanguageId, imdbid: searchImdbId),
+                                                         new SubtitleSearchParameters(subLanguageId, query: request.Name, imdbid: searchImdbId)
+                                                     };
+            var parms = new List<SubtitleSearchParameters> {
+                                                               new SubtitleSearchParameters( subLanguageId,
+                                                                   movieHash: hash,
+                                                                   movieByteSize: movieByteSize,
+                                                                   imdbid: searchImdbId ),
+                                                           };
+            parms.AddRange(subtitleSearchParameters);
+            var result = await OpenSubtitles.SearchSubtitlesAsync(parms.ToArray(), cancellationToken).ConfigureAwait(false);
+            if (!(result is MethodResponseSubtitleSearch))
+            {
+                _logger.Error("Invalid response type");
+                return new List<RemoteSubtitleInfo>();
+            }
+
+            Predicate<SubtitleSearchResult> mediaFilter =
+                x =>
+                    request.ContentType == VideoContentType.Episode
+                        ? !string.IsNullOrEmpty(x.SeriesSeason) && !string.IsNullOrEmpty(x.SeriesEpisode) &&
+                          int.Parse(x.SeriesSeason, _usCulture) == request.ParentIndexNumber &&
+                          int.Parse(x.SeriesEpisode, _usCulture) == request.IndexNumber
+                        : !string.IsNullOrEmpty(x.IDMovieImdb) && long.Parse(x.IDMovieImdb, _usCulture) == imdbId;
+
+            var results = ((MethodResponseSubtitleSearch)result).Results;
+
+            // Avoid implicitly captured closure
+            var hasCopy = hash;
+
+            return results.Where(x => x.SubBad == "0" && mediaFilter(x) && (!request.IsPerfectMatch || string.Equals(x.MovieHash, hash, StringComparison.OrdinalIgnoreCase)))
+                    .OrderBy(x => (string.Equals(x.MovieHash, hash, StringComparison.OrdinalIgnoreCase) ? 0 : 1))
+                    .ThenBy(x => Math.Abs(long.Parse(x.MovieByteSize, _usCulture) - movieByteSize))
+                    .ThenByDescending(x => int.Parse(x.SubDownloadsCnt, _usCulture))
+                    .ThenByDescending(x => double.Parse(x.SubRating, _usCulture))
+                    .Select(i => new RemoteSubtitleInfo
+                    {
+                        Author = i.UserNickName,
+                        Comment = i.SubAuthorComment,
+                        CommunityRating = float.Parse(i.SubRating, _usCulture),
+                        DownloadCount = int.Parse(i.SubDownloadsCnt, _usCulture),
+                        Format = i.SubFormat,
+                        ProviderName = Name,
+                        ThreeLetterISOLanguageName = i.SubLanguageID,
+
+                        Id = i.SubFormat + "-" + i.SubLanguageID + "-" + i.IDSubtitleFile,
+
+                        Name = i.SubFileName,
+                        DateCreated = DateTime.Parse(i.SubAddDate, _usCulture),
+                        IsHashMatch = i.MovieHash == hasCopy
+
+                    }).Where(i => !string.Equals(i.Format, "sub", StringComparison.OrdinalIgnoreCase) && !string.Equals(i.Format, "idx", StringComparison.OrdinalIgnoreCase));
+        }
+
+        public void Dispose()
+        {
+            _config.NamedConfigurationUpdating -= _config_NamedConfigurationUpdating;
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/ParserValues.cs b/MediaBrowser.MediaEncoding/Subtitles/ParserValues.cs
new file mode 100644
index 000000000..b8c2fef1e
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/ParserValues.cs
@@ -0,0 +1,7 @@
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class ParserValues
+    {
+        public const string NewLine = "\r\n";
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/SrtParser.cs b/MediaBrowser.MediaEncoding/Subtitles/SrtParser.cs
new file mode 100644
index 000000000..de6d7bc72
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/SrtParser.cs
@@ -0,0 +1,92 @@
+using MediaBrowser.Model.Extensions;
+using MediaBrowser.Model.Logging;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Text.RegularExpressions;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class SrtParser : ISubtitleParser
+    {
+        private readonly ILogger _logger;
+
+        private readonly CultureInfo _usCulture = new CultureInfo("en-US");
+
+        public SrtParser(ILogger logger)
+        {
+            _logger = logger;
+        }
+
+        public SubtitleTrackInfo Parse(Stream stream, CancellationToken cancellationToken)
+        {
+            var trackInfo = new SubtitleTrackInfo();
+            List<SubtitleTrackEvent> trackEvents = new List<SubtitleTrackEvent>();
+            using ( var reader = new StreamReader(stream))
+            {
+                string line;
+                while ((line = reader.ReadLine()) != null)
+                {
+                    cancellationToken.ThrowIfCancellationRequested();
+
+                    if (string.IsNullOrWhiteSpace(line))
+                    {
+                        continue;
+                    }
+                    var subEvent = new SubtitleTrackEvent {Id = line};
+                    line = reader.ReadLine();
+
+                    if (string.IsNullOrWhiteSpace(line))
+                    {
+                        continue;
+                    }
+                    
+                    var time = Regex.Split(line, @"[\t ]*-->[\t ]*");
+
+                    if (time.Length < 2)
+                    {
+                        // This occurs when subtitle text has an empty line as part of the text.
+                        // Need to adjust the break statement below to resolve this.
+                        _logger.Warn("Unrecognized line in srt: {0}", line);
+                        continue;
+                    }
+                    subEvent.StartPositionTicks = GetTicks(time[0]);
+                    var endTime = time[1];
+                    var idx = endTime.IndexOf(" ", StringComparison.Ordinal);
+                    if (idx > 0)
+                        endTime = endTime.Substring(0, idx);
+                    subEvent.EndPositionTicks = GetTicks(endTime);
+                    var multiline = new List<string>();
+                    while ((line = reader.ReadLine()) != null)
+                    {
+                        if (string.IsNullOrEmpty(line))
+                        {
+                            break;
+                        }
+                        multiline.Add(line);
+                    }
+                    subEvent.Text = string.Join(ParserValues.NewLine, multiline);
+                    subEvent.Text = subEvent.Text.Replace(@"\N", ParserValues.NewLine, StringComparison.OrdinalIgnoreCase);
+                    subEvent.Text = Regex.Replace(subEvent.Text, @"\{(?:\\\d?[\w.-]+(?:\([^\)]*\)|&H?[0-9A-Fa-f]+&|))+\}", string.Empty, RegexOptions.IgnoreCase);
+                    subEvent.Text = Regex.Replace(subEvent.Text, "<", "&lt;", RegexOptions.IgnoreCase);
+                    subEvent.Text = Regex.Replace(subEvent.Text, ">", "&gt;", RegexOptions.IgnoreCase);
+                    subEvent.Text = Regex.Replace(subEvent.Text, "&lt;(\\/?(font|b|u|i|s))((\\s+(\\w|\\w[\\w\\-]*\\w)(\\s*=\\s*(?:\\\".*?\\\"|'.*?'|[^'\\\">\\s]+))?)+\\s*|\\s*)(\\/?)&gt;", "<$1$3$7>", RegexOptions.IgnoreCase);
+                    trackEvents.Add(subEvent);
+                }
+            }
+            trackInfo.TrackEvents = trackEvents.ToArray();
+            return trackInfo;
+        }
+
+        long GetTicks(string time) {
+            TimeSpan span;
+            return TimeSpan.TryParseExact(time, @"hh\:mm\:ss\.fff", _usCulture, out span)
+                ? span.Ticks
+                : (TimeSpan.TryParseExact(time, @"hh\:mm\:ss\,fff", _usCulture, out span) 
+                ? span.Ticks : 0);
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/SrtWriter.cs b/MediaBrowser.MediaEncoding/Subtitles/SrtWriter.cs
new file mode 100644
index 000000000..c05929fde
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/SrtWriter.cs
@@ -0,0 +1,39 @@
+using System;
+using System.Globalization;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class SrtWriter : ISubtitleWriter
+    {
+        public void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken)
+        {
+            using (var writer = new StreamWriter(stream, Encoding.UTF8, 1024, true))
+            {
+                var index = 1;
+
+                foreach (var trackEvent in info.TrackEvents)
+                {
+                    cancellationToken.ThrowIfCancellationRequested();
+
+                    writer.WriteLine(index.ToString(CultureInfo.InvariantCulture));
+                    writer.WriteLine(@"{0:hh\:mm\:ss\,fff} --> {1:hh\:mm\:ss\,fff}", TimeSpan.FromTicks(trackEvent.StartPositionTicks), TimeSpan.FromTicks(trackEvent.EndPositionTicks));
+
+                    var text = trackEvent.Text;
+
+                    // TODO: Not sure how to handle these
+                    text = Regex.Replace(text, @"\\n", " ", RegexOptions.IgnoreCase);
+
+                    writer.WriteLine(text);
+                    writer.WriteLine(string.Empty);
+
+                    index++;
+                }
+            }
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/SsaParser.cs b/MediaBrowser.MediaEncoding/Subtitles/SsaParser.cs
new file mode 100644
index 000000000..a2cee7793
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/SsaParser.cs
@@ -0,0 +1,397 @@
+using MediaBrowser.Model.Extensions;
+using System;
+using System.IO;
+using System.Text;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+using System.Collections.Generic;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    /// <summary>
+    /// Credit to https://github.com/SubtitleEdit/subtitleedit/blob/a299dc4407a31796364cc6ad83f0d3786194ba22/src/Logic/SubtitleFormats/SubStationAlpha.cs
+    /// </summary>
+    public class SsaParser : ISubtitleParser
+    {
+        public SubtitleTrackInfo Parse(Stream stream, CancellationToken cancellationToken)
+        {
+            var trackInfo = new SubtitleTrackInfo();
+            List<SubtitleTrackEvent> trackEvents = new List<SubtitleTrackEvent>();
+
+            using (var reader = new StreamReader(stream))
+            {
+                bool eventsStarted = false;
+
+                string[] format = "Marked, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text".Split(',');
+                int indexLayer = 0;
+                int indexStart = 1;
+                int indexEnd = 2;
+                int indexStyle = 3;
+                int indexName = 4;
+                int indexEffect = 8;
+                int indexText = 9;
+                int lineNumber = 0;
+
+                var header = new StringBuilder();
+
+                string line;
+
+                while ((line = reader.ReadLine()) != null)
+                {
+                    cancellationToken.ThrowIfCancellationRequested();
+
+                    lineNumber++;
+                    if (!eventsStarted)
+                        header.AppendLine(line);
+
+                    if (line.Trim().ToLower() == "[events]")
+                    {
+                        eventsStarted = true;
+                    }
+                    else if (!string.IsNullOrEmpty(line) && line.Trim().StartsWith(";"))
+                    {
+                        // skip comment lines
+                    }
+                    else if (eventsStarted && line.Trim().Length > 0)
+                    {
+                        string s = line.Trim().ToLower();
+                        if (s.StartsWith("format:"))
+                        {
+                            if (line.Length > 10)
+                            {
+                                format = line.ToLower().Substring(8).Split(',');
+                                for (int i = 0; i < format.Length; i++)
+                                {
+                                    if (format[i].Trim().ToLower() == "layer")
+                                        indexLayer = i;
+                                    else if (format[i].Trim().ToLower() == "start")
+                                        indexStart = i;
+                                    else if (format[i].Trim().ToLower() == "end")
+                                        indexEnd = i;
+                                    else if (format[i].Trim().ToLower() == "text")
+                                        indexText = i;
+                                    else if (format[i].Trim().ToLower() == "effect")
+                                        indexEffect = i;
+                                    else if (format[i].Trim().ToLower() == "style")
+                                        indexStyle = i;
+                                }
+                            }
+                        }
+                        else if (!string.IsNullOrEmpty(s))
+                        {
+                            string text = string.Empty;
+                            string start = string.Empty;
+                            string end = string.Empty;
+                            string style = string.Empty;
+                            string layer = string.Empty;
+                            string effect = string.Empty;
+                            string name = string.Empty;
+
+                            string[] splittedLine;
+
+                            if (s.StartsWith("dialogue:"))
+                                splittedLine = line.Substring(10).Split(',');
+                            else
+                                splittedLine = line.Split(',');
+
+                            for (int i = 0; i < splittedLine.Length; i++)
+                            {
+                                if (i == indexStart)
+                                    start = splittedLine[i].Trim();
+                                else if (i == indexEnd)
+                                    end = splittedLine[i].Trim();
+                                else if (i == indexLayer)
+                                    layer = splittedLine[i];
+                                else if (i == indexEffect)
+                                    effect = splittedLine[i];
+                                else if (i == indexText)
+                                    text = splittedLine[i];
+                                else if (i == indexStyle)
+                                    style = splittedLine[i];
+                                else if (i == indexName)
+                                    name = splittedLine[i];
+                                else if (i > indexText)
+                                    text += "," + splittedLine[i];
+                            }
+
+                            try
+                            {
+                                var p = new SubtitleTrackEvent();
+
+                                p.StartPositionTicks = GetTimeCodeFromString(start);
+                                p.EndPositionTicks = GetTimeCodeFromString(end);
+                                p.Text = GetFormattedText(text);
+
+                                trackEvents.Add(p);
+                            }
+                            catch
+                            {
+                            }
+                        }
+                    }
+                } 
+                
+                //if (header.Length > 0)
+                    //subtitle.Header = header.ToString();
+
+                //subtitle.Renumber(1);
+            }
+            trackInfo.TrackEvents = trackEvents.ToArray();
+            return trackInfo;
+        }
+
+        private static long GetTimeCodeFromString(string time)
+        {
+            // h:mm:ss.cc
+            string[] timeCode = time.Split(':', '.');
+            return new TimeSpan(0, int.Parse(timeCode[0]),
+                                int.Parse(timeCode[1]),
+                                int.Parse(timeCode[2]),
+                                int.Parse(timeCode[3]) * 10).Ticks;
+        }
+
+        public static string GetFormattedText(string text)
+        {
+            text = text.Replace("\\n", ParserValues.NewLine, StringComparison.OrdinalIgnoreCase);
+
+            bool italic = false;
+
+            for (int i = 0; i < 10; i++) // just look ten times...
+            {
+                if (text.Contains(@"{\fn"))
+                {
+                    int start = text.IndexOf(@"{\fn");
+                    int end = text.IndexOf('}', start);
+                    if (end > 0 && !text.Substring(start).StartsWith("{\\fn}"))
+                    {
+                        string fontName = text.Substring(start + 4, end - (start + 4));
+                        string extraTags = string.Empty;
+                        CheckAndAddSubTags(ref fontName, ref extraTags, out italic);
+                        text = text.Remove(start, end - start + 1);
+                        if (italic)
+                            text = text.Insert(start, "<font face=\"" + fontName + "\"" + extraTags + "><i>");
+                        else
+                            text = text.Insert(start, "<font face=\"" + fontName + "\"" + extraTags + ">");
+
+                        int indexOfEndTag = text.IndexOf("{\\fn}", start);
+                        if (indexOfEndTag > 0)
+                            text = text.Remove(indexOfEndTag, "{\\fn}".Length).Insert(indexOfEndTag, "</font>");
+                        else
+                            text += "</font>";
+                    }
+                }
+
+                if (text.Contains(@"{\fs"))
+                {
+                    int start = text.IndexOf(@"{\fs");
+                    int end = text.IndexOf('}', start);
+                    if (end > 0 && !text.Substring(start).StartsWith("{\\fs}"))
+                    {
+                        string fontSize = text.Substring(start + 4, end - (start + 4));
+                        string extraTags = string.Empty;
+                        CheckAndAddSubTags(ref fontSize, ref extraTags, out italic);
+                        if (IsInteger(fontSize))
+                        {
+                            text = text.Remove(start, end - start + 1);
+                            if (italic)
+                                text = text.Insert(start, "<font size=\"" + fontSize + "\"" + extraTags + "><i>");
+                            else
+                                text = text.Insert(start, "<font size=\"" + fontSize + "\"" + extraTags + ">");
+
+                            int indexOfEndTag = text.IndexOf("{\\fs}", start);
+                            if (indexOfEndTag > 0)
+                                text = text.Remove(indexOfEndTag, "{\\fs}".Length).Insert(indexOfEndTag, "</font>");
+                            else
+                                text += "</font>";
+                        }
+                    }
+                }
+
+                if (text.Contains(@"{\c"))
+                {
+                    int start = text.IndexOf(@"{\c");
+                    int end = text.IndexOf('}', start);
+                    if (end > 0 && !text.Substring(start).StartsWith("{\\c}"))
+                    {
+                        string color = text.Substring(start + 4, end - (start + 4));
+                        string extraTags = string.Empty;
+                        CheckAndAddSubTags(ref color, ref extraTags, out italic);
+
+                        color = color.Replace("&", string.Empty).TrimStart('H');
+                        color = color.PadLeft(6, '0');
+
+                        // switch to rrggbb from bbggrr
+                        color = "#" + color.Remove(color.Length - 6) + color.Substring(color.Length - 2, 2) + color.Substring(color.Length - 4, 2) + color.Substring(color.Length - 6, 2);
+                        color = color.ToLower();
+
+                        text = text.Remove(start, end - start + 1);
+                        if (italic)
+                            text = text.Insert(start, "<font color=\"" + color + "\"" + extraTags + "><i>");
+                        else
+                            text = text.Insert(start, "<font color=\"" + color + "\"" + extraTags + ">");
+                        int indexOfEndTag = text.IndexOf("{\\c}", start);
+                        if (indexOfEndTag > 0)
+                            text = text.Remove(indexOfEndTag, "{\\c}".Length).Insert(indexOfEndTag, "</font>");
+                        else
+                            text += "</font>";
+                    }
+                }
+
+                if (text.Contains(@"{\1c")) // "1" specifices primary color
+                {
+                    int start = text.IndexOf(@"{\1c");
+                    int end = text.IndexOf('}', start);
+                    if (end > 0 && !text.Substring(start).StartsWith("{\\1c}"))
+                    {
+                        string color = text.Substring(start + 5, end - (start + 5));
+                        string extraTags = string.Empty;
+                        CheckAndAddSubTags(ref color, ref extraTags, out italic);
+
+                        color = color.Replace("&", string.Empty).TrimStart('H');
+                        color = color.PadLeft(6, '0');
+
+                        // switch to rrggbb from bbggrr
+                        color = "#" + color.Remove(color.Length - 6) + color.Substring(color.Length - 2, 2) + color.Substring(color.Length - 4, 2) + color.Substring(color.Length - 6, 2);
+                        color = color.ToLower();
+
+                        text = text.Remove(start, end - start + 1);
+                        if (italic)
+                            text = text.Insert(start, "<font color=\"" + color + "\"" + extraTags + "><i>");
+                        else
+                            text = text.Insert(start, "<font color=\"" + color + "\"" + extraTags + ">");
+                        text += "</font>";
+                    }
+                }
+
+            }
+
+            text = text.Replace(@"{\i1}", "<i>");
+            text = text.Replace(@"{\i0}", "</i>");
+            text = text.Replace(@"{\i}", "</i>");
+            if (CountTagInText(text, "<i>") > CountTagInText(text, "</i>"))
+                text += "</i>";
+
+            text = text.Replace(@"{\u1}", "<u>");
+            text = text.Replace(@"{\u0}", "</u>");
+            text = text.Replace(@"{\u}", "</u>");
+            if (CountTagInText(text, "<u>") > CountTagInText(text, "</u>"))
+                text += "</u>";
+
+            text = text.Replace(@"{\b1}", "<b>");
+            text = text.Replace(@"{\b0}", "</b>");
+            text = text.Replace(@"{\b}", "</b>");
+            if (CountTagInText(text, "<b>") > CountTagInText(text, "</b>"))
+                text += "</b>";
+
+            return text;
+        }
+
+        private static bool IsInteger(string s)
+        {
+            int i;
+            if (int.TryParse(s, out i))
+                return true;
+            return false;
+        }
+
+        private static int CountTagInText(string text, string tag)
+        {
+            int count = 0;
+            int index = text.IndexOf(tag);
+            while (index >= 0)
+            {
+                count++;
+                if (index == text.Length)
+                    return count;
+                index = text.IndexOf(tag, index + 1);
+            }
+            return count;
+        }
+
+        private static void CheckAndAddSubTags(ref string tagName, ref string extraTags, out bool italic)
+        {
+            italic = false;
+            int indexOfSPlit = tagName.IndexOf(@"\");
+            if (indexOfSPlit > 0)
+            {
+                string rest = tagName.Substring(indexOfSPlit).TrimStart('\\');
+                tagName = tagName.Remove(indexOfSPlit);
+
+                for (int i = 0; i < 10; i++)
+                {
+                    if (rest.StartsWith("fs") && rest.Length > 2)
+                    {
+                        indexOfSPlit = rest.IndexOf(@"\");
+                        string fontSize = rest;
+                        if (indexOfSPlit > 0)
+                        {
+                            fontSize = rest.Substring(0, indexOfSPlit);
+                            rest = rest.Substring(indexOfSPlit).TrimStart('\\');
+                        }
+                        else
+                        {
+                            rest = string.Empty;
+                        }
+                        extraTags += " size=\"" + fontSize.Substring(2) + "\"";
+                    }
+                    else if (rest.StartsWith("fn") && rest.Length > 2)
+                    {
+                        indexOfSPlit = rest.IndexOf(@"\");
+                        string fontName = rest;
+                        if (indexOfSPlit > 0)
+                        {
+                            fontName = rest.Substring(0, indexOfSPlit);
+                            rest = rest.Substring(indexOfSPlit).TrimStart('\\');
+                        }
+                        else
+                        {
+                            rest = string.Empty;
+                        }
+                        extraTags += " face=\"" + fontName.Substring(2) + "\"";
+                    }
+                    else if (rest.StartsWith("c") && rest.Length > 2)
+                    {
+                        indexOfSPlit = rest.IndexOf(@"\");
+                        string fontColor = rest;
+                        if (indexOfSPlit > 0)
+                        {
+                            fontColor = rest.Substring(0, indexOfSPlit);
+                            rest = rest.Substring(indexOfSPlit).TrimStart('\\');
+                        }
+                        else
+                        {
+                            rest = string.Empty;
+                        }
+
+                        string color = fontColor.Substring(2);
+                        color = color.Replace("&", string.Empty).TrimStart('H');
+                        color = color.PadLeft(6, '0');
+                        // switch to rrggbb from bbggrr
+                        color = "#" + color.Remove(color.Length - 6) + color.Substring(color.Length - 2, 2) + color.Substring(color.Length - 4, 2) + color.Substring(color.Length - 6, 2);
+                        color = color.ToLower();
+
+                        extraTags += " color=\"" + color + "\"";
+                    }
+                    else if (rest.StartsWith("i1") && rest.Length > 1)
+                    {
+                        indexOfSPlit = rest.IndexOf(@"\");
+                        italic = true;
+                        if (indexOfSPlit > 0)
+                        {
+                            rest = rest.Substring(indexOfSPlit).TrimStart('\\');
+                        }
+                        else
+                        {
+                            rest = string.Empty;
+                        }
+                    }
+                    else if (rest.Length > 0 && rest.Contains("\\"))
+                    {
+                        indexOfSPlit = rest.IndexOf(@"\");
+                        rest = rest.Substring(indexOfSPlit).TrimStart('\\');
+                    }
+                }
+            }
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/SubtitleEncoder.cs b/MediaBrowser.MediaEncoding/Subtitles/SubtitleEncoder.cs
new file mode 100644
index 000000000..d565ff3e2
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/SubtitleEncoder.cs
@@ -0,0 +1,733 @@
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Common.Extensions;
+using MediaBrowser.Common.Net;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.MediaEncoding;
+using MediaBrowser.Model.Entities;
+using MediaBrowser.Model.Logging;
+using MediaBrowser.Model.MediaInfo;
+using MediaBrowser.Model.Serialization;
+using System;
+using System.Collections.Concurrent;
+using System.Diagnostics;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using MediaBrowser.Model.IO;
+using MediaBrowser.Model.Diagnostics;
+using MediaBrowser.Model.Dto;
+using MediaBrowser.Model.Text;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class SubtitleEncoder : ISubtitleEncoder
+    {
+        private readonly ILibraryManager _libraryManager;
+        private readonly ILogger _logger;
+        private readonly IApplicationPaths _appPaths;
+        private readonly IFileSystem _fileSystem;
+        private readonly IMediaEncoder _mediaEncoder;
+        private readonly IJsonSerializer _json;
+        private readonly IHttpClient _httpClient;
+        private readonly IMediaSourceManager _mediaSourceManager;
+        private readonly IProcessFactory _processFactory;
+        private readonly ITextEncoding _textEncoding;
+
+        public SubtitleEncoder(ILibraryManager libraryManager, ILogger logger, IApplicationPaths appPaths, IFileSystem fileSystem, IMediaEncoder mediaEncoder, IJsonSerializer json, IHttpClient httpClient, IMediaSourceManager mediaSourceManager, IProcessFactory processFactory, ITextEncoding textEncoding)
+        {
+            _libraryManager = libraryManager;
+            _logger = logger;
+            _appPaths = appPaths;
+            _fileSystem = fileSystem;
+            _mediaEncoder = mediaEncoder;
+            _json = json;
+            _httpClient = httpClient;
+            _processFactory = processFactory;
+            _textEncoding = textEncoding;
+        }
+
+        private string SubtitleCachePath
+        {
+            get
+            {
+                return Path.Combine(_appPaths.DataPath, "subtitles");
+            }
+        }
+
+        private Stream ConvertSubtitles(Stream stream,
+            string inputFormat,
+            string outputFormat,
+            long startTimeTicks,
+            long? endTimeTicks,
+            bool preserveOriginalTimestamps,
+            CancellationToken cancellationToken)
+        {
+            var ms = new MemoryStream();
+
+            try
+            {
+                var reader = GetReader(inputFormat, true);
+
+                var trackInfo = reader.Parse(stream, cancellationToken);
+
+                FilterEvents(trackInfo, startTimeTicks, endTimeTicks, preserveOriginalTimestamps);
+
+                var writer = GetWriter(outputFormat);
+
+                writer.Write(trackInfo, ms, cancellationToken);
+                ms.Position = 0;
+            }
+            catch
+            {
+                ms.Dispose();
+                throw;
+            }
+
+            return ms;
+        }
+
+        private void FilterEvents(SubtitleTrackInfo track, long startPositionTicks, long? endTimeTicks, bool preserveTimestamps)
+        {
+            // Drop subs that are earlier than what we're looking for
+            track.TrackEvents = track.TrackEvents
+                .SkipWhile(i => (i.StartPositionTicks - startPositionTicks) < 0 || (i.EndPositionTicks - startPositionTicks) < 0)
+                .ToArray();
+
+            if (endTimeTicks.HasValue)
+            {
+                var endTime = endTimeTicks.Value;
+
+                track.TrackEvents = track.TrackEvents
+                    .TakeWhile(i => i.StartPositionTicks <= endTime)
+                    .ToArray();
+            }
+
+            if (!preserveTimestamps)
+            {
+                foreach (var trackEvent in track.TrackEvents)
+                {
+                    trackEvent.EndPositionTicks -= startPositionTicks;
+                    trackEvent.StartPositionTicks -= startPositionTicks;
+                }
+            }
+        }
+
+        async Task<Stream> ISubtitleEncoder.GetSubtitles(BaseItem item, string mediaSourceId, int subtitleStreamIndex, string outputFormat, long startTimeTicks, long endTimeTicks, bool preserveOriginalTimestamps, CancellationToken cancellationToken)
+        {
+            if (item == null)
+            {
+                throw new ArgumentNullException("item");
+            }
+            if (string.IsNullOrWhiteSpace(mediaSourceId))
+            {
+                throw new ArgumentNullException("mediaSourceId");
+            }
+
+            // TODO network path substition useful ?
+            var mediaSources = await _mediaSourceManager.GetPlayackMediaSources(item, null, true, true, cancellationToken).ConfigureAwait(false);
+
+            var mediaSource = mediaSources
+                .First(i => string.Equals(i.Id, mediaSourceId, StringComparison.OrdinalIgnoreCase));
+
+            var subtitleStream = mediaSource.MediaStreams
+               .First(i => i.Type == MediaStreamType.Subtitle && i.Index == subtitleStreamIndex);
+
+            var subtitle = await GetSubtitleStream(mediaSource, subtitleStream, cancellationToken)
+                        .ConfigureAwait(false);
+
+            var inputFormat = subtitle.Item2;
+            var writer = TryGetWriter(outputFormat);
+
+            // Return the original if we don't have any way of converting it
+            if (writer == null)
+            {
+                return subtitle.Item1;
+            }
+
+            // Return the original if the same format is being requested
+            // Character encoding was already handled in GetSubtitleStream
+            if (string.Equals(inputFormat, outputFormat, StringComparison.OrdinalIgnoreCase))
+            {
+                return subtitle.Item1;
+            }
+
+            using (var stream = subtitle.Item1)
+            {
+                return  ConvertSubtitles(stream, inputFormat, outputFormat, startTimeTicks, endTimeTicks, preserveOriginalTimestamps, cancellationToken);
+            }
+        }
+
+        private async Task<Tuple<Stream, string>> GetSubtitleStream(MediaSourceInfo mediaSource,
+            MediaStream subtitleStream,
+            CancellationToken cancellationToken)
+        {
+            var inputFiles = new[] { mediaSource.Path };
+
+            if (mediaSource.VideoType.HasValue)
+            {
+                if (mediaSource.VideoType.Value == VideoType.BluRay || mediaSource.VideoType.Value == VideoType.Dvd)
+                {
+                    var mediaSourceItem = (Video)_libraryManager.GetItemById(new Guid(mediaSource.Id));
+                    inputFiles = mediaSourceItem.GetPlayableStreamFileNames(_mediaEncoder).ToArray();
+                }
+            }
+
+            var fileInfo = await GetReadableFile(mediaSource.Path, inputFiles, mediaSource.Protocol, subtitleStream, cancellationToken).ConfigureAwait(false);
+
+            var stream = await GetSubtitleStream(fileInfo.Item1, subtitleStream.Language, fileInfo.Item2, fileInfo.Item4, cancellationToken).ConfigureAwait(false);
+
+            return new Tuple<Stream, string>(stream, fileInfo.Item3);
+        }
+
+        private async Task<Stream> GetSubtitleStream(string path, string language, MediaProtocol protocol, bool requiresCharset, CancellationToken cancellationToken)
+        {
+            if (requiresCharset)
+            {
+                var bytes = await GetBytes(path, protocol, cancellationToken).ConfigureAwait(false);
+
+                var charset = _textEncoding.GetDetectedEncodingName(bytes, bytes.Length, language, true);
+                _logger.Debug("charset {0} detected for {1}", charset ?? "null", path);
+
+                if (!string.IsNullOrEmpty(charset))
+                {
+                    using (var inputStream = new MemoryStream(bytes))
+                    {
+                        using (var reader = new StreamReader(inputStream, _textEncoding.GetEncodingFromCharset(charset)))
+                        {
+                            var text = await reader.ReadToEndAsync().ConfigureAwait(false);
+
+                            bytes = Encoding.UTF8.GetBytes(text);
+
+                            return new MemoryStream(bytes);
+                        }
+                    }
+                }
+            }
+
+            return _fileSystem.OpenRead(path);
+        }
+
+        private async Task<Tuple<string, MediaProtocol, string, bool>> GetReadableFile(string mediaPath,
+            string[] inputFiles,
+            MediaProtocol protocol,
+            MediaStream subtitleStream,
+            CancellationToken cancellationToken)
+        {
+            if (!subtitleStream.IsExternal)
+            {
+                string outputFormat;
+                string outputCodec;
+
+                if (string.Equals(subtitleStream.Codec, "ass", StringComparison.OrdinalIgnoreCase) ||
+                    string.Equals(subtitleStream.Codec, "ssa", StringComparison.OrdinalIgnoreCase) ||
+                    string.Equals(subtitleStream.Codec, "srt", StringComparison.OrdinalIgnoreCase))
+                {
+                    // Extract    
+                    outputCodec = "copy";
+                    outputFormat = subtitleStream.Codec;
+                }
+                else if (string.Equals(subtitleStream.Codec, "subrip", StringComparison.OrdinalIgnoreCase))
+                {
+                    // Extract    
+                    outputCodec = "copy";
+                    outputFormat = "srt";
+                }
+                else
+                {
+                    // Extract    
+                    outputCodec = "srt";
+                    outputFormat = "srt";
+                }
+
+                // Extract    
+                var outputPath = GetSubtitleCachePath(mediaPath, protocol, subtitleStream.Index, "." + outputFormat);
+
+                await ExtractTextSubtitle(inputFiles, protocol, subtitleStream.Index, outputCodec, outputPath, cancellationToken)
+                        .ConfigureAwait(false);
+
+                return new Tuple<string, MediaProtocol, string, bool>(outputPath, MediaProtocol.File, outputFormat, false);
+            }
+
+            var currentFormat = (Path.GetExtension(subtitleStream.Path) ?? subtitleStream.Codec)
+                .TrimStart('.');
+
+            if (GetReader(currentFormat, false) == null)
+            {
+                // Convert    
+                var outputPath = GetSubtitleCachePath(mediaPath, protocol, subtitleStream.Index, ".srt");
+
+                await ConvertTextSubtitleToSrt(subtitleStream.Path, subtitleStream.Language, protocol, outputPath, cancellationToken).ConfigureAwait(false);
+
+                return new Tuple<string, MediaProtocol, string, bool>(outputPath, MediaProtocol.File, "srt", true);
+            }
+
+            return new Tuple<string, MediaProtocol, string, bool>(subtitleStream.Path, protocol, currentFormat, true);
+        }
+
+        private ISubtitleParser GetReader(string format, bool throwIfMissing)
+        {
+            if (string.IsNullOrEmpty(format))
+            {
+                throw new ArgumentNullException("format");
+            }
+
+            if (string.Equals(format, SubtitleFormat.SRT, StringComparison.OrdinalIgnoreCase))
+            {
+                return new SrtParser(_logger);
+            }
+            if (string.Equals(format, SubtitleFormat.SSA, StringComparison.OrdinalIgnoreCase))
+            {
+                return new SsaParser();
+            }
+            if (string.Equals(format, SubtitleFormat.ASS, StringComparison.OrdinalIgnoreCase))
+            {
+                return new AssParser();
+            }
+
+            if (throwIfMissing)
+            {
+                throw new ArgumentException("Unsupported format: " + format);
+            }
+
+            return null;
+        }
+
+        private ISubtitleWriter TryGetWriter(string format)
+        {
+            if (string.IsNullOrEmpty(format))
+            {
+                throw new ArgumentNullException("format");
+            }
+
+            if (string.Equals(format, "json", StringComparison.OrdinalIgnoreCase))
+            {
+                return new JsonWriter(_json);
+            }
+            if (string.Equals(format, SubtitleFormat.SRT, StringComparison.OrdinalIgnoreCase))
+            {
+                return new SrtWriter();
+            }
+            if (string.Equals(format, SubtitleFormat.VTT, StringComparison.OrdinalIgnoreCase))
+            {
+                return new VttWriter();
+            }
+            if (string.Equals(format, SubtitleFormat.TTML, StringComparison.OrdinalIgnoreCase))
+            {
+                return new TtmlWriter();
+            }
+
+            return null;
+        }
+
+        private ISubtitleWriter GetWriter(string format)
+        {
+            var writer = TryGetWriter(format);
+
+            if (writer != null)
+            {
+                return writer;
+            }
+
+            throw new ArgumentException("Unsupported format: " + format);
+        }
+
+        /// <summary>
+        /// The _semaphoreLocks
+        /// </summary>
+        private readonly ConcurrentDictionary<string, SemaphoreSlim> _semaphoreLocks =
+            new ConcurrentDictionary<string, SemaphoreSlim>();
+
+        /// <summary>
+        /// Gets the lock.
+        /// </summary>
+        /// <param name="filename">The filename.</param>
+        /// <returns>System.Object.</returns>
+        private SemaphoreSlim GetLock(string filename)
+        {
+            return _semaphoreLocks.GetOrAdd(filename, key => new SemaphoreSlim(1, 1));
+        }
+
+        /// <summary>
+        /// Converts the text subtitle to SRT.
+        /// </summary>
+        /// <param name="inputPath">The input path.</param>
+        /// <param name="inputProtocol">The input protocol.</param>
+        /// <param name="outputPath">The output path.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>Task.</returns>
+        private async Task ConvertTextSubtitleToSrt(string inputPath, string language, MediaProtocol inputProtocol, string outputPath, CancellationToken cancellationToken)
+        {
+            var semaphore = GetLock(outputPath);
+
+            await semaphore.WaitAsync(cancellationToken).ConfigureAwait(false);
+
+            try
+            {
+                if (!_fileSystem.FileExists(outputPath))
+                {
+                    await ConvertTextSubtitleToSrtInternal(inputPath, language, inputProtocol, outputPath, cancellationToken).ConfigureAwait(false);
+                }
+            }
+            finally
+            {
+                semaphore.Release();
+            }
+        }
+
+        /// <summary>
+        /// Converts the text subtitle to SRT internal.
+        /// </summary>
+        /// <param name="inputPath">The input path.</param>
+        /// <param name="inputProtocol">The input protocol.</param>
+        /// <param name="outputPath">The output path.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>Task.</returns>
+        /// <exception cref="System.ArgumentNullException">
+        /// inputPath
+        /// or
+        /// outputPath
+        /// </exception>
+        private async Task ConvertTextSubtitleToSrtInternal(string inputPath, string language, MediaProtocol inputProtocol, string outputPath, CancellationToken cancellationToken)
+        {
+            if (string.IsNullOrEmpty(inputPath))
+            {
+                throw new ArgumentNullException("inputPath");
+            }
+
+            if (string.IsNullOrEmpty(outputPath))
+            {
+                throw new ArgumentNullException("outputPath");
+            }
+
+            _fileSystem.CreateDirectory(_fileSystem.GetDirectoryName(outputPath));
+
+            var encodingParam = await GetSubtitleFileCharacterSet(inputPath, language, inputProtocol, cancellationToken).ConfigureAwait(false);
+
+            if (!string.IsNullOrEmpty(encodingParam))
+            {
+                encodingParam = " -sub_charenc " + encodingParam;
+            }
+
+            var process = _processFactory.Create(new ProcessOptions
+            {
+                CreateNoWindow = true,
+                UseShellExecute = false,
+                FileName = _mediaEncoder.EncoderPath,
+                Arguments = string.Format("{0} -i \"{1}\" -c:s srt \"{2}\"", encodingParam, inputPath, outputPath),
+
+                IsHidden = true,
+                ErrorDialog = false
+            });
+
+            _logger.Info("{0} {1}", process.StartInfo.FileName, process.StartInfo.Arguments);
+
+            try
+            {
+                process.Start();
+            }
+            catch (Exception ex)
+            {
+                _logger.ErrorException("Error starting ffmpeg", ex);
+
+                throw;
+            }
+
+            var ranToCompletion = await process.WaitForExitAsync(300000).ConfigureAwait(false);
+
+            if (!ranToCompletion)
+            {
+                try
+                {
+                    _logger.Info("Killing ffmpeg subtitle conversion process");
+
+                    process.Kill();
+                }
+                catch (Exception ex)
+                {
+                    _logger.ErrorException("Error killing subtitle conversion process", ex);
+                }
+            }
+
+            var exitCode = ranToCompletion ? process.ExitCode : -1;
+
+            process.Dispose();
+
+            var failed = false;
+
+            if (exitCode == -1)
+            {
+                failed = true;
+
+                if (_fileSystem.FileExists(outputPath))
+                {
+                    try
+                    {
+                        _logger.Info("Deleting converted subtitle due to failure: ", outputPath);
+                        _fileSystem.DeleteFile(outputPath);
+                    }
+                    catch (IOException ex)
+                    {
+                        _logger.ErrorException("Error deleting converted subtitle {0}", ex, outputPath);
+                    }
+                }
+            }
+            else if (!_fileSystem.FileExists(outputPath))
+            {
+                failed = true;
+            }
+
+            if (failed)
+            {
+                var msg = string.Format("ffmpeg subtitle conversion failed for {0}", inputPath);
+
+                _logger.Error(msg);
+
+                throw new Exception(msg);
+            }
+            await SetAssFont(outputPath).ConfigureAwait(false);
+
+            _logger.Info("ffmpeg subtitle conversion succeeded for {0}", inputPath);
+        }
+
+        /// <summary>
+        /// Extracts the text subtitle.
+        /// </summary>
+        /// <param name="inputFiles">The input files.</param>
+        /// <param name="protocol">The protocol.</param>
+        /// <param name="subtitleStreamIndex">Index of the subtitle stream.</param>
+        /// <param name="outputCodec">The output codec.</param>
+        /// <param name="outputPath">The output path.</param>
+        /// <param name="cancellationToken">The cancellation token.</param>
+        /// <returns>Task.</returns>
+        /// <exception cref="System.ArgumentException">Must use inputPath list overload</exception>
+        private async Task ExtractTextSubtitle(string[] inputFiles, MediaProtocol protocol, int subtitleStreamIndex,
+            string outputCodec, string outputPath, CancellationToken cancellationToken)
+        {
+            var semaphore = GetLock(outputPath);
+
+            await semaphore.WaitAsync(cancellationToken).ConfigureAwait(false);
+
+            try
+            {
+                if (!_fileSystem.FileExists(outputPath))
+                {
+                    await ExtractTextSubtitleInternal(_mediaEncoder.GetInputArgument(inputFiles, protocol), subtitleStreamIndex, outputCodec, outputPath, cancellationToken).ConfigureAwait(false);
+                }
+            }
+            finally
+            {
+                semaphore.Release();
+            }
+        }
+
+        private async Task ExtractTextSubtitleInternal(string inputPath, int subtitleStreamIndex,
+            string outputCodec, string outputPath, CancellationToken cancellationToken)
+        {
+            if (string.IsNullOrEmpty(inputPath))
+            {
+                throw new ArgumentNullException("inputPath");
+            }
+
+            if (string.IsNullOrEmpty(outputPath))
+            {
+                throw new ArgumentNullException("outputPath");
+            }
+
+            _fileSystem.CreateDirectory(_fileSystem.GetDirectoryName(outputPath));
+
+            var processArgs = string.Format("-i {0} -map 0:{1} -an -vn -c:s {2} \"{3}\"", inputPath,
+                subtitleStreamIndex, outputCodec, outputPath);
+
+            var process = _processFactory.Create(new ProcessOptions
+            {
+                CreateNoWindow = true,
+                UseShellExecute = false,
+
+                FileName = _mediaEncoder.EncoderPath,
+                Arguments = processArgs,
+                IsHidden = true,
+                ErrorDialog = false
+            });
+
+            _logger.Info("{0} {1}", process.StartInfo.FileName, process.StartInfo.Arguments);
+
+            try
+            {
+                process.Start();
+            }
+            catch (Exception ex)
+            {
+                _logger.ErrorException("Error starting ffmpeg", ex);
+
+                throw;
+            }
+
+            var ranToCompletion = await process.WaitForExitAsync(300000).ConfigureAwait(false);
+
+            if (!ranToCompletion)
+            {
+                try
+                {
+                    _logger.Info("Killing ffmpeg subtitle extraction process");
+
+                    process.Kill();
+                }
+                catch (Exception ex)
+                {
+                    _logger.ErrorException("Error killing subtitle extraction process", ex);
+                }
+            }
+
+            var exitCode = ranToCompletion ? process.ExitCode : -1;
+
+            process.Dispose();
+
+            var failed = false;
+
+            if (exitCode == -1)
+            {
+                failed = true;
+
+                try
+                {
+                    _logger.Info("Deleting extracted subtitle due to failure: {0}", outputPath);
+                    _fileSystem.DeleteFile(outputPath);
+                }
+                catch (FileNotFoundException)
+                {
+
+                }
+                catch (IOException ex)
+                {
+                    _logger.ErrorException("Error deleting extracted subtitle {0}", ex, outputPath);
+                }
+            }
+            else if (!_fileSystem.FileExists(outputPath))
+            {
+                failed = true;
+            }
+
+            if (failed)
+            {
+                var msg = string.Format("ffmpeg subtitle extraction failed for {0} to {1}", inputPath, outputPath);
+
+                _logger.Error(msg);
+
+                throw new Exception(msg);
+            }
+            else
+            {
+                var msg = string.Format("ffmpeg subtitle extraction completed for {0} to {1}", inputPath, outputPath);
+
+                _logger.Info(msg);
+            }
+
+            if (string.Equals(outputCodec, "ass", StringComparison.OrdinalIgnoreCase))
+            {
+                await SetAssFont(outputPath).ConfigureAwait(false);
+            }
+        }
+
+        /// <summary>
+        /// Sets the ass font.
+        /// </summary>
+        /// <param name="file">The file.</param>
+        /// <returns>Task.</returns>
+        private async Task SetAssFont(string file)
+        {
+            _logger.Info("Setting ass font within {0}", file);
+
+            string text;
+            Encoding encoding;
+
+            using (var fileStream = _fileSystem.OpenRead(file))
+            {
+                using (var reader = new StreamReader(fileStream, true))
+                {
+                    encoding = reader.CurrentEncoding;
+
+                    text = await reader.ReadToEndAsync().ConfigureAwait(false);
+                }
+            }
+
+            var newText = text.Replace(",Arial,", ",Arial Unicode MS,");
+
+            if (!string.Equals(text, newText))
+            {
+                using (var fileStream = _fileSystem.GetFileStream(file, FileOpenMode.Create, FileAccessMode.Write, FileShareMode.Read))
+                {
+                    using (var writer = new StreamWriter(fileStream, encoding))
+                    {
+                        writer.Write(newText);
+                    }
+                }
+            }
+        }
+
+        private string GetSubtitleCachePath(string mediaPath, MediaProtocol protocol, int subtitleStreamIndex, string outputSubtitleExtension)
+        {
+            if (protocol == MediaProtocol.File)
+            {
+                var ticksParam = string.Empty;
+
+                var date = _fileSystem.GetLastWriteTimeUtc(mediaPath);
+
+                var filename = (mediaPath + "_" + subtitleStreamIndex.ToString(CultureInfo.InvariantCulture) + "_" + date.Ticks.ToString(CultureInfo.InvariantCulture) + ticksParam).GetMD5() + outputSubtitleExtension;
+
+                var prefix = filename.Substring(0, 1);
+
+                return Path.Combine(SubtitleCachePath, prefix, filename);
+            }
+            else
+            {
+                var filename = (mediaPath + "_" + subtitleStreamIndex.ToString(CultureInfo.InvariantCulture)).GetMD5() + outputSubtitleExtension;
+
+                var prefix = filename.Substring(0, 1);
+
+                return Path.Combine(SubtitleCachePath, prefix, filename);
+            }
+        }
+
+        public async Task<string> GetSubtitleFileCharacterSet(string path, string language, MediaProtocol protocol, CancellationToken cancellationToken)
+        {
+            var bytes = await GetBytes(path, protocol, cancellationToken).ConfigureAwait(false);
+
+            var charset = _textEncoding.GetDetectedEncodingName(bytes, bytes.Length, language, true);
+
+            _logger.Debug("charset {0} detected for {1}", charset ?? "null", path);
+
+            return charset;
+        }
+
+        private async Task<byte[]> GetBytes(string path, MediaProtocol protocol, CancellationToken cancellationToken)
+        {
+            if (protocol == MediaProtocol.Http)
+            {
+                HttpRequestOptions opts = new HttpRequestOptions();
+                opts.Url = path;
+                opts.CancellationToken = cancellationToken;
+                using (var file = await _httpClient.Get(opts).ConfigureAwait(false))
+                {
+                    using (var memoryStream = new MemoryStream())
+                    {
+                        await file.CopyToAsync(memoryStream).ConfigureAwait(false);
+                        memoryStream.Position = 0;
+
+                        return memoryStream.ToArray();
+                    }
+                }
+            }
+            if (protocol == MediaProtocol.File)
+            {
+                return _fileSystem.ReadAllBytes(path);
+            }
+
+            throw new ArgumentOutOfRangeException("protocol");
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/MediaBrowser.MediaEncoding/Subtitles/TtmlWriter.cs b/MediaBrowser.MediaEncoding/Subtitles/TtmlWriter.cs
new file mode 100644
index 000000000..c32005f89
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/TtmlWriter.cs
@@ -0,0 +1,60 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class TtmlWriter : ISubtitleWriter
+    {
+        public void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken)
+        {
+            // Example: https://github.com/zmalltalker/ttml2vtt/blob/master/data/sample.xml
+            // Parser example: https://github.com/mozilla/popcorn-js/blob/master/parsers/parserTTML/popcorn.parserTTML.js
+
+            using (var writer = new StreamWriter(stream, Encoding.UTF8, 1024, true))
+            {
+                writer.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
+                writer.WriteLine("<tt xmlns=\"http://www.w3.org/ns/ttml\" xmlns:tts=\"http://www.w3.org/2006/04/ttaf1#styling\" lang=\"no\">");
+
+                writer.WriteLine("<head>");
+                writer.WriteLine("<styling>");
+                writer.WriteLine("<style id=\"italic\" tts:fontStyle=\"italic\" />");
+                writer.WriteLine("<style id=\"left\" tts:textAlign=\"left\" />");
+                writer.WriteLine("<style id=\"center\" tts:textAlign=\"center\" />");
+                writer.WriteLine("<style id=\"right\" tts:textAlign=\"right\" />");
+                writer.WriteLine("</styling>");
+                writer.WriteLine("</head>");
+
+                writer.WriteLine("<body>");
+                writer.WriteLine("<div>");
+
+                foreach (var trackEvent in info.TrackEvents)
+                {
+                    var text = trackEvent.Text;
+
+                    text = Regex.Replace(text, @"\\n", "<br/>", RegexOptions.IgnoreCase);
+
+                    writer.WriteLine("<p begin=\"{0}\" dur=\"{1}\">{2}</p>",
+                        trackEvent.StartPositionTicks,
+                        (trackEvent.EndPositionTicks - trackEvent.StartPositionTicks),
+                        text);
+                }
+
+                writer.WriteLine("</div>");
+                writer.WriteLine("</body>");
+                
+                writer.WriteLine("</tt>");
+            }
+        }
+
+        private string FormatTime(long ticks)
+        {
+            var time = TimeSpan.FromTicks(ticks);
+
+            return string.Format(@"{0:hh\:mm\:ss\,fff}", time);
+        }
+    }
+}
diff --git a/MediaBrowser.MediaEncoding/Subtitles/VttWriter.cs b/MediaBrowser.MediaEncoding/Subtitles/VttWriter.cs
new file mode 100644
index 000000000..092add992
--- /dev/null
+++ b/MediaBrowser.MediaEncoding/Subtitles/VttWriter.cs
@@ -0,0 +1,44 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading;
+using MediaBrowser.Model.MediaInfo;
+
+namespace MediaBrowser.MediaEncoding.Subtitles
+{
+    public class VttWriter : ISubtitleWriter
+    {
+        public void Write(SubtitleTrackInfo info, Stream stream, CancellationToken cancellationToken)
+        {
+            using (var writer = new StreamWriter(stream, Encoding.UTF8, 1024, true))
+            {
+                writer.WriteLine("WEBVTT");
+                writer.WriteLine(string.Empty);
+                foreach (var trackEvent in info.TrackEvents)
+                {
+                    cancellationToken.ThrowIfCancellationRequested();
+
+                    TimeSpan startTime = TimeSpan.FromTicks(trackEvent.StartPositionTicks);
+                    TimeSpan endTime = TimeSpan.FromTicks(trackEvent.EndPositionTicks);
+
+                    // make sure the start and end times are different and seqential
+                    if (endTime.TotalMilliseconds <= startTime.TotalMilliseconds)
+                    {
+                        endTime = startTime.Add(TimeSpan.FromMilliseconds(1));
+                    }
+
+                    writer.WriteLine(@"{0:hh\:mm\:ss\.fff} --> {1:hh\:mm\:ss\.fff}", startTime, endTime);
+
+                    var text = trackEvent.Text;
+
+                    // TODO: Not sure how to handle these
+                    text = Regex.Replace(text, @"\\n", " ", RegexOptions.IgnoreCase);
+
+                    writer.WriteLine(text);
+                    writer.WriteLine(string.Empty);
+                }
+            }
+        }
+    }
+}