jellyfin-server/MediaBrowser.MediaEncoding/Subtitles/SubtitleEncoder.cs
2020-04-11 13:46:31 -04:00

777 lines
28 KiB
C#

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.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.Dto;
using MediaBrowser.Model.Entities;
using MediaBrowser.Model.IO;
using MediaBrowser.Model.MediaInfo;
using Microsoft.Extensions.Logging;
using UtfUnknown;
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 IHttpClient _httpClient;
private readonly IMediaSourceManager _mediaSourceManager;
public SubtitleEncoder(
ILibraryManager libraryManager,
ILogger<SubtitleEncoder> logger,
IApplicationPaths appPaths,
IFileSystem fileSystem,
IMediaEncoder mediaEncoder,
IHttpClient httpClient,
IMediaSourceManager mediaSourceManager)
{
_libraryManager = libraryManager;
_logger = logger;
_appPaths = appPaths;
_fileSystem = fileSystem;
_mediaEncoder = mediaEncoder;
_httpClient = httpClient;
_mediaSourceManager = mediaSourceManager;
}
private string SubtitleCachePath => 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 > 0)
{
track.TrackEvents = track.TrackEvents
.TakeWhile(i => i.StartPositionTicks <= endTimeTicks)
.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(nameof(item));
}
if (string.IsNullOrWhiteSpace(mediaSourceId))
{
throw new ArgumentNullException(nameof(mediaSourceId));
}
var mediaSources = await _mediaSourceManager.GetPlaybackMediaSources(item, null, true, false, 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.format;
var writer = TryGetWriter(outputFormat);
// Return the original if we don't have any way of converting it
if (writer == null)
{
return subtitle.stream;
}
// 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.stream;
}
using (var stream = subtitle.stream)
{
return ConvertSubtitles(stream, inputFormat, outputFormat, startTimeTicks, endTimeTicks, preserveOriginalTimestamps, cancellationToken);
}
}
private async Task<(Stream stream, string format)> GetSubtitleStream(
MediaSourceInfo mediaSource,
MediaStream subtitleStream,
CancellationToken cancellationToken)
{
string[] inputFiles;
if (mediaSource.VideoType.HasValue
&& (mediaSource.VideoType.Value == VideoType.BluRay || mediaSource.VideoType.Value == VideoType.Dvd))
{
var mediaSourceItem = (Video)_libraryManager.GetItemById(new Guid(mediaSource.Id));
inputFiles = mediaSourceItem.GetPlayableStreamFileNames();
}
else
{
inputFiles = new[] { mediaSource.Path };
}
var fileInfo = await GetReadableFile(mediaSource.Path, inputFiles, mediaSource.Protocol, subtitleStream, cancellationToken).ConfigureAwait(false);
var stream = await GetSubtitleStream(fileInfo.Path, fileInfo.Protocol, fileInfo.IsExternal, cancellationToken).ConfigureAwait(false);
return (stream, fileInfo.Format);
}
private async Task<Stream> GetSubtitleStream(string path, MediaProtocol protocol, bool requiresCharset, CancellationToken cancellationToken)
{
if (requiresCharset)
{
using (var stream = await GetStream(path, protocol, cancellationToken).ConfigureAwait(false))
{
var result = CharsetDetector.DetectFromStream(stream).Detected;
stream.Position = 0;
if (result != null)
{
_logger.LogDebug("charset {CharSet} detected for {Path}", result.EncodingName, path);
using var reader = new StreamReader(stream, result.Encoding);
var text = await reader.ReadToEndAsync().ConfigureAwait(false);
return new MemoryStream(Encoding.UTF8.GetBytes(text));
}
}
}
return File.OpenRead(path);
}
private async Task<SubtitleInfo> 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 SubtitleInfo(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 SubtitleInfo(outputPath, MediaProtocol.File, "srt", true);
}
return new SubtitleInfo(subtitleStream.Path, protocol, currentFormat, true);
}
private struct SubtitleInfo
{
public SubtitleInfo(string path, MediaProtocol protocol, string format, bool isExternal)
{
Path = path;
Protocol = protocol;
Format = format;
IsExternal = isExternal;
}
public string Path { get; set; }
public MediaProtocol Protocol { get; set; }
public string Format { get; set; }
public bool IsExternal { get; set; }
}
private ISubtitleParser GetReader(string format, bool throwIfMissing)
{
if (string.IsNullOrEmpty(format))
{
throw new ArgumentNullException(nameof(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(nameof(format));
}
if (string.Equals(format, "json", StringComparison.OrdinalIgnoreCase))
{
return new JsonWriter();
}
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 (!File.Exists(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="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(nameof(inputPath));
}
if (string.IsNullOrEmpty(outputPath))
{
throw new ArgumentNullException(nameof(outputPath));
}
Directory.CreateDirectory(Path.GetDirectoryName(outputPath));
var encodingParam = await GetSubtitleFileCharacterSet(inputPath, language, inputProtocol, cancellationToken).ConfigureAwait(false);
// FFmpeg automatically convert character encoding when it is UTF-16
// If we specify character encoding, it rejects with "do not specify a character encoding" and "Unable to recode subtitle event"
if ((inputPath.EndsWith(".smi") || inputPath.EndsWith(".sami")) && (encodingParam == "UTF-16BE" || encodingParam == "UTF-16LE"))
{
encodingParam = "";
}
else if (!string.IsNullOrEmpty(encodingParam))
{
encodingParam = " -sub_charenc " + encodingParam;
}
int exitCode;
using (var process = new Process
{
StartInfo = new ProcessStartInfo
{
CreateNoWindow = true,
UseShellExecute = false,
FileName = _mediaEncoder.EncoderPath,
Arguments = string.Format("{0} -i \"{1}\" -c:s srt \"{2}\"", encodingParam, inputPath, outputPath),
WindowStyle = ProcessWindowStyle.Hidden,
ErrorDialog = false
},
EnableRaisingEvents = true
})
{
_logger.LogInformation("{0} {1}", process.StartInfo.FileName, process.StartInfo.Arguments);
try
{
process.Start();
}
catch (Exception ex)
{
_logger.LogError(ex, "Error starting ffmpeg");
throw;
}
var ranToCompletion = await process.WaitForExitAsync(TimeSpan.FromMinutes(5)).ConfigureAwait(false);
if (!ranToCompletion)
{
try
{
_logger.LogInformation("Killing ffmpeg subtitle conversion process");
process.Kill();
}
catch (Exception ex)
{
_logger.LogError(ex, "Error killing subtitle conversion process");
}
}
exitCode = ranToCompletion ? process.ExitCode : -1;
}
var failed = false;
if (exitCode == -1)
{
failed = true;
if (File.Exists(outputPath))
{
try
{
_logger.LogInformation("Deleting converted subtitle due to failure: ", outputPath);
_fileSystem.DeleteFile(outputPath);
}
catch (IOException ex)
{
_logger.LogError(ex, "Error deleting converted subtitle {Path}", outputPath);
}
}
}
else if (!File.Exists(outputPath))
{
failed = true;
}
if (failed)
{
_logger.LogError("ffmpeg subtitle conversion failed for {Path}", inputPath);
throw new Exception(
string.Format(CultureInfo.InvariantCulture, "ffmpeg subtitle conversion failed for {0}", inputPath));
}
await SetAssFont(outputPath).ConfigureAwait(false);
_logger.LogInformation("ffmpeg subtitle conversion succeeded for {Path}", 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="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 (!File.Exists(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(nameof(inputPath));
}
if (string.IsNullOrEmpty(outputPath))
{
throw new ArgumentNullException(nameof(outputPath));
}
Directory.CreateDirectory(Path.GetDirectoryName(outputPath));
var processArgs = string.Format(
CultureInfo.InvariantCulture,
"-i {0} -map 0:{1} -an -vn -c:s {2} \"{3}\"",
inputPath,
subtitleStreamIndex,
outputCodec,
outputPath);
int exitCode;
using (var process = new Process
{
StartInfo = new ProcessStartInfo
{
CreateNoWindow = true,
UseShellExecute = false,
FileName = _mediaEncoder.EncoderPath,
Arguments = processArgs,
WindowStyle = ProcessWindowStyle.Hidden,
ErrorDialog = false
},
EnableRaisingEvents = true
})
{
_logger.LogInformation("{File} {Arguments}", process.StartInfo.FileName, process.StartInfo.Arguments);
try
{
process.Start();
}
catch (Exception ex)
{
_logger.LogError(ex, "Error starting ffmpeg");
throw;
}
var ranToCompletion = await process.WaitForExitAsync(TimeSpan.FromMinutes(5)).ConfigureAwait(false);
if (!ranToCompletion)
{
try
{
_logger.LogWarning("Killing ffmpeg subtitle extraction process");
process.Kill();
}
catch (Exception ex)
{
_logger.LogError(ex, "Error killing subtitle extraction process");
}
}
exitCode = ranToCompletion ? process.ExitCode : -1;
}
var failed = false;
if (exitCode == -1)
{
failed = true;
try
{
_logger.LogWarning("Deleting extracted subtitle due to failure: {Path}", outputPath);
_fileSystem.DeleteFile(outputPath);
}
catch (FileNotFoundException)
{
}
catch (IOException ex)
{
_logger.LogError(ex, "Error deleting extracted subtitle {Path}", outputPath);
}
}
else if (!File.Exists(outputPath))
{
failed = true;
}
if (failed)
{
var msg = $"ffmpeg subtitle extraction failed for {inputPath} to {outputPath}";
_logger.LogError(msg);
throw new Exception(msg);
}
else
{
var msg = $"ffmpeg subtitle extraction completed for {inputPath} to {outputPath}";
_logger.LogInformation(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.LogInformation("Setting ass font within {File}", file);
string text;
Encoding encoding;
using (var fileStream = File.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 = new FileStream(file, FileMode.Create, FileAccess.Write, FileShare.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);
}
}
/// <inheritdoc />
public async Task<string> GetSubtitleFileCharacterSet(string path, string language, MediaProtocol protocol, CancellationToken cancellationToken)
{
using (var stream = await GetStream(path, protocol, cancellationToken).ConfigureAwait(false))
{
var charset = CharsetDetector.DetectFromStream(stream).Detected?.EncodingName;
// UTF16 is automatically converted to UTF8 by FFmpeg, do not specify a character encoding
if ((path.EndsWith(".ass") || path.EndsWith(".ssa"))
&& (string.Equals(charset, "utf-16le", StringComparison.OrdinalIgnoreCase)
|| string.Equals(charset, "utf-16be", StringComparison.OrdinalIgnoreCase)))
{
charset = "";
}
_logger.LogDebug("charset {0} detected for {Path}", charset ?? "null", path);
return charset;
}
}
private Task<Stream> GetStream(string path, MediaProtocol protocol, CancellationToken cancellationToken)
{
switch (protocol)
{
case MediaProtocol.Http:
var opts = new HttpRequestOptions()
{
Url = path,
CancellationToken = cancellationToken,
// Needed for seeking
BufferContent = true
};
return _httpClient.Get(opts);
case MediaProtocol.File:
return Task.FromResult<Stream>(File.OpenRead(path));
default:
throw new ArgumentOutOfRangeException(nameof(protocol));
}
}
}
}