diff options
Diffstat (limited to 'Emby.Server.Implementations/Library/MediaStreamSelector.cs')
| -rw-r--r-- | Emby.Server.Implementations/Library/MediaStreamSelector.cs | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/Emby.Server.Implementations/Library/MediaStreamSelector.cs b/Emby.Server.Implementations/Library/MediaStreamSelector.cs new file mode 100644 index 000000000..5d4c5a452 --- /dev/null +++ b/Emby.Server.Implementations/Library/MediaStreamSelector.cs @@ -0,0 +1,217 @@ +using MediaBrowser.Model.Configuration; +using MediaBrowser.Model.Entities; +using System; +using System.Collections.Generic; +using System.Linq; + +namespace Emby.Server.Implementations.Library +{ + public static class MediaStreamSelector + { + public static int? GetDefaultAudioStreamIndex(List<MediaStream> streams, string[] preferredLanguages, bool preferDefaultTrack) + { + streams = GetSortedStreams(streams, MediaStreamType.Audio, preferredLanguages) + .ToList(); + + if (preferDefaultTrack) + { + var defaultStream = streams.FirstOrDefault(i => i.IsDefault); + + if (defaultStream != null) + { + return defaultStream.Index; + } + } + + var stream = streams.FirstOrDefault(); + + if (stream != null) + { + return stream.Index; + } + + return null; + } + + public static int? GetDefaultSubtitleStreamIndex(List<MediaStream> streams, + string[] preferredLanguages, + SubtitlePlaybackMode mode, + string audioTrackLanguage) + { + streams = GetSortedStreams(streams, MediaStreamType.Subtitle, preferredLanguages) + .ToList(); + + MediaStream stream = null; + + if (mode == SubtitlePlaybackMode.None) + { + return null; + } + + if (mode == SubtitlePlaybackMode.Default) + { + // Prefer embedded metadata over smart logic + + stream = streams.FirstOrDefault(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase)) ?? + streams.FirstOrDefault(s => s.IsForced) ?? + streams.FirstOrDefault(s => s.IsDefault); + + // if the audio language is not understood by the user, load their preferred subs, if there are any + if (stream == null && !preferredLanguages.Contains(audioTrackLanguage, StringComparer.OrdinalIgnoreCase)) + { + stream = streams.Where(s => !s.IsForced).FirstOrDefault(s => preferredLanguages.Contains(s.Language, StringComparer.OrdinalIgnoreCase)); + } + } + else if (mode == SubtitlePlaybackMode.Smart) + { + // Prefer smart logic over embedded metadata + + // if the audio language is not understood by the user, load their preferred subs, if there are any + if (!preferredLanguages.Contains(audioTrackLanguage, StringComparer.OrdinalIgnoreCase)) + { + stream = streams.Where(s => !s.IsForced).FirstOrDefault(s => preferredLanguages.Contains(s.Language, StringComparer.OrdinalIgnoreCase)) ?? + streams.FirstOrDefault(s => preferredLanguages.Contains(s.Language, StringComparer.OrdinalIgnoreCase)); + } + } + else if (mode == SubtitlePlaybackMode.Always) + { + // always load the most suitable full subtitles + stream = streams.FirstOrDefault(s => !s.IsForced); + } + else if (mode == SubtitlePlaybackMode.OnlyForced) + { + // always load the most suitable full subtitles + stream = streams.FirstOrDefault(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase)) ?? + streams.FirstOrDefault(s => s.IsForced); + } + + // load forced subs if we have found no suitable full subtitles + stream = stream ?? streams.FirstOrDefault(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase)); + + if (stream != null) + { + return stream.Index; + } + + return null; + } + + private static IEnumerable<MediaStream> GetSortedStreams(IEnumerable<MediaStream> streams, MediaStreamType type, string[] languagePreferences) + { + // Give some preferance to external text subs for better performance + return streams.Where(i => i.Type == type) + .OrderBy(i => + { + var index = FindIndex(languagePreferences, i.Language); + + return index == -1 ? 100 : index; + }) + .ThenBy(i => GetBooleanOrderBy(i.IsDefault)) + .ThenBy(i => GetBooleanOrderBy(i.SupportsExternalStream)) + .ThenBy(i => GetBooleanOrderBy(i.IsTextSubtitleStream)) + .ThenBy(i => GetBooleanOrderBy(i.IsExternal)) + .ThenBy(i => i.Index); + } + + public static void SetSubtitleStreamScores(List<MediaStream> streams, + string[] preferredLanguages, + SubtitlePlaybackMode mode, + string audioTrackLanguage) + { + if (mode == SubtitlePlaybackMode.None) + { + return; + } + + streams = GetSortedStreams(streams, MediaStreamType.Subtitle, preferredLanguages) + .ToList(); + + var filteredStreams = new List<MediaStream>(); + + if (mode == SubtitlePlaybackMode.Default) + { + // Prefer embedded metadata over smart logic + filteredStreams = streams.Where(s => s.IsForced || s.IsDefault) + .ToList(); + } + else if (mode == SubtitlePlaybackMode.Smart) + { + // Prefer smart logic over embedded metadata + if (!preferredLanguages.Contains(audioTrackLanguage, StringComparer.OrdinalIgnoreCase)) + { + filteredStreams = streams.Where(s => !s.IsForced && preferredLanguages.Contains(s.Language, StringComparer.OrdinalIgnoreCase)) + .ToList(); + } + } + else if (mode == SubtitlePlaybackMode.Always) + { + // always load the most suitable full subtitles + filteredStreams = streams.Where(s => !s.IsForced) + .ToList(); + } + else if (mode == SubtitlePlaybackMode.OnlyForced) + { + // always load the most suitable full subtitles + filteredStreams = streams.Where(s => s.IsForced).ToList(); + } + + // load forced subs if we have found no suitable full subtitles + if (filteredStreams.Count == 0) + { + filteredStreams = streams + .Where(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase)) + .ToList(); + } + + foreach (var stream in filteredStreams) + { + stream.Score = GetSubtitleScore(stream, preferredLanguages); + } + } + + private static int FindIndex(string[] list, string value) + { + for (var i=0; i< list.Length; i++) + { + if (string.Equals(list[i], value, StringComparison.OrdinalIgnoreCase)) + { + return i; + } + } + + return -1; + } + + private static int GetSubtitleScore(MediaStream stream, string[] languagePreferences) + { + var values = new List<int>(); + + var index = FindIndex(languagePreferences, stream.Language); + + values.Add(index == -1 ? 0 : 100 - index); + + values.Add(stream.IsForced ? 1 : 0); + values.Add(stream.IsDefault ? 1 : 0); + values.Add(stream.SupportsExternalStream ? 1 : 0); + values.Add(stream.IsTextSubtitleStream ? 1 : 0); + values.Add(stream.IsExternal ? 1 : 0); + + values.Reverse(); + var scale = 1; + var score = 0; + + foreach (var value in values) + { + score += scale * (value + 1); + scale *= 10; + } + + return score; + } + + private static int GetBooleanOrderBy(bool value) + { + return value ? 0 : 1; + } + } +} |