move encoding methods to shared classes

1 files changed, 7 insertions, 791 deletions

diff --git a/MediaBrowser.MediaEncoding/Encoder/BaseEncoder.cs b/MediaBrowser.MediaEncoding/Encoder/BaseEncoder.cs
index 7654ec1d7..b0b37f2d6 100644
--- a/MediaBrowser.MediaEncoding/Encoder/BaseEncoder.cs
+++ b/MediaBrowser.MediaEncoding/Encoder/BaseEncoder.cs
@@ -36,6 +36,8 @@ namespace MediaBrowser.MediaEncoding.Encoder
 
         protected readonly CultureInfo UsCulture = new CultureInfo("en-US");
 
+        protected EncodingHelper EncodingHelper;
+
         protected BaseEncoder(MediaEncoder mediaEncoder,
             ILogger logger,
             IServerConfigurationManager configurationManager,
@@ -56,6 +58,8 @@ namespace MediaBrowser.MediaEncoding.Encoder
             SubtitleEncoder = subtitleEncoder;
             MediaSourceManager = mediaSourceManager;
             ProcessFactory = processFactory;
+
+            EncodingHelper = new EncodingHelper(MediaEncoder, ConfigurationManager, FileSystem, SubtitleEncoder);
         }
 
         public async Task<EncodingJob> Start(EncodingJobOptions options,
@@ -63,7 +67,7 @@ namespace MediaBrowser.MediaEncoding.Encoder
             CancellationToken cancellationToken)
         {
             var encodingJob = await new EncodingJobFactory(Logger, LibraryManager, MediaSourceManager, ConfigurationManager)
-                .CreateJob(options, IsVideoEncoder, progress, cancellationToken).ConfigureAwait(false);
+                .CreateJob(options, EncodingHelper, IsVideoEncoder, progress, cancellationToken).ConfigureAwait(false);
 
             encodingJob.OutputFilePath = GetOutputFilePath(encodingJob);
             FileSystem.CreateDirectory(Path.GetDirectoryName(encodingJob.OutputFilePath));
@@ -286,72 +290,6 @@ namespace MediaBrowser.MediaEncoding.Encoder
         }
 
         /// <summary>
-        /// Gets the number of threads.
-        /// </summary>
-        /// <returns>System.Int32.</returns>
-        protected int GetNumberOfThreads(EncodingJob job, bool isWebm)
-        {
-            return job.Options.CpuCoreLimit ?? 0;
-        }
-
-        protected string GetInputModifier(EncodingJob state, bool genPts = true)
-        {
-            var inputModifier = string.Empty;
-
-            var probeSize = GetProbeSizeArgument(state);
-            inputModifier += " " + probeSize;
-            inputModifier = inputModifier.Trim();
-
-            var userAgentParam = GetUserAgentParam(state);
-
-            if (!string.IsNullOrWhiteSpace(userAgentParam))
-            {
-                inputModifier += " " + userAgentParam;
-            }
-
-            inputModifier = inputModifier.Trim();
-
-            inputModifier += " " + GetFastSeekCommandLineParameter(state.Options);
-            inputModifier = inputModifier.Trim();
-
-            if (state.IsVideoRequest && genPts)
-            {
-                inputModifier += " -fflags +genpts";
-            }
-
-            if (!string.IsNullOrEmpty(state.InputAudioSync))
-            {
-                inputModifier += " -async " + state.InputAudioSync;
-            }
-
-            if (!string.IsNullOrEmpty(state.InputVideoSync))
-            {
-                inputModifier += " -vsync " + state.InputVideoSync;
-            }
-
-            if (state.ReadInputAtNativeFramerate)
-            {
-                inputModifier += " -re";
-            }
-
-            var videoDecoder = GetVideoDecoder(state);
-            if (!string.IsNullOrWhiteSpace(videoDecoder))
-            {
-                inputModifier += " " + videoDecoder;
-            }
-
-            //if (state.IsVideoRequest)
-            //{
-            //    if (string.Equals(state.OutputContainer, "mkv", StringComparison.OrdinalIgnoreCase))
-            //    {
-            //        //inputModifier += " -noaccurate_seek";
-            //    }
-            //}
-
-            return inputModifier;
-        }
-
-        /// <summary>
         /// Gets the name of the output video codec
         /// </summary>
         /// <param name="state">The state.</param>
@@ -405,130 +343,6 @@ namespace MediaBrowser.MediaEncoding.Encoder
             return null;
         }
 
-        private string GetUserAgentParam(EncodingJob state)
-        {
-            string useragent = null;
-
-            state.RemoteHttpHeaders.TryGetValue("User-Agent", out useragent);
-
-            if (!string.IsNullOrWhiteSpace(useragent))
-            {
-                return "-user-agent \"" + useragent + "\"";
-            }
-
-            return string.Empty;
-        }
-
-        /// <summary>
-        /// Gets the probe size argument.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <returns>System.String.</returns>
-        private string GetProbeSizeArgument(EncodingJob state)
-        {
-            if (state.PlayableStreamFileNames.Count > 0)
-            {
-                return MediaEncoder.GetProbeSizeAndAnalyzeDurationArgument(state.PlayableStreamFileNames.ToArray(), state.InputProtocol);
-            }
-
-            return MediaEncoder.GetProbeSizeAndAnalyzeDurationArgument(new[] { state.MediaPath }, state.InputProtocol);
-        }
-
-        /// <summary>
-        /// Gets the fast seek command line parameter.
-        /// </summary>
-        /// <param name="request">The request.</param>
-        /// <returns>System.String.</returns>
-        /// <value>The fast seek command line parameter.</value>
-        protected string GetFastSeekCommandLineParameter(EncodingJobOptions request)
-        {
-            var time = request.StartTimeTicks ?? 0;
-
-            if (time > 0)
-            {
-                return string.Format("-ss {0}", MediaEncoder.GetTimeParameter(time));
-            }
-
-            return string.Empty;
-        }
-
-        /// <summary>
-        /// Gets the input argument.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <returns>System.String.</returns>
-        protected string GetInputArgument(EncodingJob state)
-        {
-            var arg = string.Format("-i {0}", GetInputPathArgument(state));
-
-            if (state.SubtitleStream != null && state.Options.SubtitleMethod == SubtitleDeliveryMethod.Encode)
-            {
-                if (state.SubtitleStream.IsExternal && !state.SubtitleStream.IsTextSubtitleStream)
-                {
-                    if (state.VideoStream != null && state.VideoStream.Width.HasValue)
-                    {
-                        // This is hacky but not sure how to get the exact subtitle resolution
-                        double height = state.VideoStream.Width.Value;
-                        height /= 16;
-                        height *= 9;
-
-                        arg += string.Format(" -canvas_size {0}:{1}", state.VideoStream.Width.Value.ToString(CultureInfo.InvariantCulture), Convert.ToInt32(height).ToString(CultureInfo.InvariantCulture));
-                    }
-
-                    var subtitlePath = state.SubtitleStream.Path;
-
-                    if (string.Equals(Path.GetExtension(subtitlePath), ".sub", StringComparison.OrdinalIgnoreCase))
-                    {
-                        var idxFile = Path.ChangeExtension(subtitlePath, ".idx");
-                        if (FileSystem.FileExists(idxFile))
-                        {
-                            subtitlePath = idxFile;
-                        }
-                    }
-
-                    arg += " -i \"" + subtitlePath + "\"";
-                }
-            }
-
-            if (state.IsVideoRequest)
-            {
-                var encodingOptions = GetEncodingOptions();
-                var videoEncoder = EncodingJobFactory.GetVideoEncoder(MediaEncoder, state, encodingOptions);
-                if (videoEncoder.IndexOf("vaapi", StringComparison.OrdinalIgnoreCase) != -1)
-                {
-                    var hasGraphicalSubs = state.SubtitleStream != null && !state.SubtitleStream.IsTextSubtitleStream && state.Options.SubtitleMethod == SubtitleDeliveryMethod.Encode;
-                    var hwOutputFormat = "vaapi";
-
-                    if (hasGraphicalSubs)
-                    {
-                        hwOutputFormat = "yuv420p";
-                    }
-
-                    arg = "-hwaccel vaapi -hwaccel_output_format " + hwOutputFormat + " -vaapi_device " + encodingOptions.VaapiDevice + " " + arg;
-                }
-            }
-
-            return arg.Trim();
-        }
-
-        private string GetInputPathArgument(EncodingJob state)
-        {
-            var protocol = state.InputProtocol;
-            var mediaPath = state.MediaPath ?? string.Empty;
-
-            var inputPath = new[] { mediaPath };
-
-            if (state.IsInputVideo)
-            {
-                if (!(state.VideoType == VideoType.Iso && state.IsoMount == null))
-                {
-                    inputPath = MediaEncoderHelpers.GetInputArgument(FileSystem, mediaPath, state.InputProtocol, state.IsoMount, state.PlayableStreamFileNames);
-                }
-            }
-
-            return MediaEncoder.GetInputArgument(inputPath, protocol);
-        }
-
         private async Task AcquireResources(EncodingJob state, CancellationToken cancellationToken)
         {
             if (state.VideoType == VideoType.Iso && state.IsoType.HasValue && IsoManager.CanMount(state.MediaPath))
@@ -544,11 +358,11 @@ namespace MediaBrowser.MediaEncoding.Encoder
 
                 }, false, cancellationToken).ConfigureAwait(false);
 
-                AttachMediaSourceInfo(state, liveStreamResponse.MediaSource, state.Options);
+                EncodingHelper.AttachMediaSourceInfo(state, liveStreamResponse.MediaSource, null);
 
                 if (state.IsVideoRequest)
                 {
-                    EncodingJobFactory.TryStreamCopy(state, state.Options);
+                    EncodingHelper.TryStreamCopy(state);
                 }
             }
 
@@ -557,603 +371,5 @@ namespace MediaBrowser.MediaEncoding.Encoder
                 await Task.Delay(state.MediaSource.BufferMs.Value, cancellationToken).ConfigureAwait(false);
             }
         }
-
-        private void AttachMediaSourceInfo(EncodingJob state,
-          MediaSourceInfo mediaSource,
-          EncodingJobOptions videoRequest)
-        {
-            EncodingJobFactory.AttachMediaSourceInfo(state, mediaSource, videoRequest);
-        }
-
-        /// <summary>
-        /// Gets the internal graphical subtitle param.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <param name="outputVideoCodec">The output video codec.</param>
-        /// <returns>System.String.</returns>
-        protected async Task<string> GetGraphicalSubtitleParam(EncodingJob state, string outputVideoCodec)
-        {
-            var outputSizeParam = string.Empty;
-
-            var request = state.Options;
-
-            // Add resolution params, if specified
-            if (request.Width.HasValue || request.Height.HasValue || request.MaxHeight.HasValue || request.MaxWidth.HasValue)
-            {
-                outputSizeParam = await GetOutputSizeParam(state, outputVideoCodec).ConfigureAwait(false);
-                outputSizeParam = outputSizeParam.TrimEnd('"');
-
-                if (string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-                {
-                    outputSizeParam = "," + outputSizeParam.Substring(outputSizeParam.IndexOf("format", StringComparison.OrdinalIgnoreCase));
-                }
-                else
-                {
-                    outputSizeParam = "," + outputSizeParam.Substring(outputSizeParam.IndexOf("scale", StringComparison.OrdinalIgnoreCase));
-                }
-            }
-
-            if (string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase) && outputSizeParam.Length == 0)
-            {
-                outputSizeParam = ",format=nv12|vaapi,hwupload";
-            }
-
-            var videoSizeParam = string.Empty;
-
-            if (state.VideoStream != null && state.VideoStream.Width.HasValue && state.VideoStream.Height.HasValue)
-            {
-                videoSizeParam = string.Format(",scale={0}:{1}", state.VideoStream.Width.Value.ToString(UsCulture), state.VideoStream.Height.Value.ToString(UsCulture));
-            }
-
-            var mapPrefix = state.SubtitleStream.IsExternal ?
-                1 :
-                0;
-
-            var subtitleStreamIndex = state.SubtitleStream.IsExternal
-                ? 0
-                : state.SubtitleStream.Index;
-
-            return string.Format(" -filter_complex \"[{0}:{1}]format=yuva444p{4},lut=u=128:v=128:y=gammaval(.3)[sub] ; [0:{2}] [sub] overlay{3}\"",
-                mapPrefix.ToString(UsCulture),
-                subtitleStreamIndex.ToString(UsCulture),
-                state.VideoStream.Index.ToString(UsCulture),
-                outputSizeParam,
-                videoSizeParam);
-        }
-
-        /// <summary>
-        /// Gets the video bitrate to specify on the command line
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <param name="videoEncoder">The video codec.</param>
-        /// <returns>System.String.</returns>
-        protected string GetVideoQualityParam(EncodingJob state, string videoEncoder)
-        {
-            var param = string.Empty;
-
-            var isVc1 = state.VideoStream != null &&
-                string.Equals(state.VideoStream.Codec, "vc1", StringComparison.OrdinalIgnoreCase);
-
-            if (string.Equals(videoEncoder, "libx264", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-preset superfast";
-
-                param += " -crf 23";
-            }
-
-            else if (string.Equals(videoEncoder, "libx265", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-preset fast";
-
-                param += " -crf 28";
-            }
-
-            // h264 (h264_qsv)
-            else if (string.Equals(videoEncoder, "h264_qsv", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-preset 7 -look_ahead 0";
-
-            }
-
-            // h264 (h264_nvenc)
-            else if (string.Equals(videoEncoder, "h264_nvenc", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-preset llhq";
-            }
-
-            // webm
-            else if (string.Equals(videoEncoder, "libvpx", StringComparison.OrdinalIgnoreCase))
-            {
-                // Values 0-3, 0 being highest quality but slower
-                var profileScore = 0;
-
-                string crf;
-                var qmin = "0";
-                var qmax = "50";
-
-                crf = "10";
-
-                if (isVc1)
-                {
-                    profileScore++;
-                }
-
-                // Max of 2
-                profileScore = Math.Min(profileScore, 2);
-
-                // http://www.webmproject.org/docs/encoder-parameters/
-                param = string.Format("-speed 16 -quality good -profile:v {0} -slices 8 -crf {1} -qmin {2} -qmax {3}",
-                    profileScore.ToString(UsCulture),
-                    crf,
-                    qmin,
-                    qmax);
-            }
-
-            else if (string.Equals(videoEncoder, "mpeg4", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-mbd rd -flags +mv4+aic -trellis 2 -cmp 2 -subcmp 2 -bf 2";
-            }
-
-            // asf/wmv
-            else if (string.Equals(videoEncoder, "wmv2", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-qmin 2";
-            }
-
-            else if (string.Equals(videoEncoder, "msmpeg4", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-mbd 2";
-            }
-
-            param += GetVideoBitrateParam(state, videoEncoder);
-
-            var framerate = GetFramerateParam(state);
-            if (framerate.HasValue)
-            {
-                param += string.Format(" -r {0}", framerate.Value.ToString(UsCulture));
-            }
-
-            if (!string.IsNullOrEmpty(state.OutputVideoSync))
-            {
-                param += " -vsync " + state.OutputVideoSync;
-            }
-
-            if (!string.IsNullOrEmpty(state.Options.Profile))
-            {
-                if (!string.Equals(videoEncoder, "h264_omx", StringComparison.OrdinalIgnoreCase) &&
-                    !string.Equals(videoEncoder, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-                {
-                    // not supported by h264_omx
-                    param += " -profile:v " + state.Options.Profile;
-                }
-            }
-
-            var levelString = state.Options.Level.HasValue ? state.Options.Level.Value.ToString(CultureInfo.InvariantCulture) : null;
-
-            if (!string.IsNullOrEmpty(levelString))
-            {
-                levelString = NormalizeTranscodingLevel(state.OutputVideoCodec, levelString);
-
-                // h264_qsv and h264_nvenc expect levels to be expressed as a decimal. libx264 supports decimal and non-decimal format
-                // also needed for libx264 due to https://trac.ffmpeg.org/ticket/3307
-                if (string.Equals(videoEncoder, "h264_qsv", StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(videoEncoder, "h264_nvenc", StringComparison.OrdinalIgnoreCase) ||
-                    string.Equals(videoEncoder, "libx264", StringComparison.OrdinalIgnoreCase))
-                {
-                    switch (levelString)
-                    {
-                        case "30":
-                            param += " -level 3.0";
-                            break;
-                        case "31":
-                            param += " -level 3.1";
-                            break;
-                        case "32":
-                            param += " -level 3.2";
-                            break;
-                        case "40":
-                            param += " -level 4.0";
-                            break;
-                        case "41":
-                            param += " -level 4.1";
-                            break;
-                        case "42":
-                            param += " -level 4.2";
-                            break;
-                        case "50":
-                            param += " -level 5.0";
-                            break;
-                        case "51":
-                            param += " -level 5.1";
-                            break;
-                        case "52":
-                            param += " -level 5.2";
-                            break;
-                        default:
-                            param += " -level " + levelString;
-                            break;
-                    }
-                }
-                else if (!string.Equals(videoEncoder, "h264_omx", StringComparison.OrdinalIgnoreCase))
-                {
-                    param += " -level " + levelString;
-                }
-            }
-
-            if (!string.Equals(videoEncoder, "h264_omx", StringComparison.OrdinalIgnoreCase) &&
-                !string.Equals(videoEncoder, "h264_qsv", StringComparison.OrdinalIgnoreCase) &&
-                !string.Equals(videoEncoder, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-            {
-                param = "-pix_fmt yuv420p " + param;
-            }
-
-            return param;
-        }
-
-        private string NormalizeTranscodingLevel(string videoCodec, string level)
-        {
-            double requestLevel;
-
-            // Clients may direct play higher than level 41, but there's no reason to transcode higher
-            if (double.TryParse(level, NumberStyles.Any, UsCulture, out requestLevel))
-            {
-                if (string.Equals(videoCodec, "h264", StringComparison.OrdinalIgnoreCase))
-                {
-                    if (requestLevel > 41)
-                    {
-                        return "41";
-                    }
-                }
-            }
-
-            return level;
-        }
-
-        protected string GetVideoBitrateParam(EncodingJob state, string videoCodec)
-        {
-            var bitrate = state.OutputVideoBitrate;
-
-            if (bitrate.HasValue)
-            {
-                if (string.Equals(videoCodec, "libvpx", StringComparison.OrdinalIgnoreCase))
-                {
-                    // With vpx when crf is used, b:v becomes a max rate
-                    // https://trac.ffmpeg.org/wiki/vpxEncodingGuide. But higher bitrate source files -b:v causes judder so limite the bitrate but dont allow it to "saturate" the bitrate. So dont contrain it down just up.
-                    return string.Format(" -maxrate:v {0} -bufsize:v ({0}*2) -b:v {0}", bitrate.Value.ToString(UsCulture));
-                }
-
-                if (string.Equals(videoCodec, "msmpeg4", StringComparison.OrdinalIgnoreCase))
-                {
-                    return string.Format(" -b:v {0}", bitrate.Value.ToString(UsCulture));
-                }
-
-                if (string.Equals(videoCodec, "libx264", StringComparison.OrdinalIgnoreCase))
-                {
-                    // h264
-                    return string.Format(" -maxrate {0} -bufsize {1}",
-                        bitrate.Value.ToString(UsCulture),
-                        (bitrate.Value * 2).ToString(UsCulture));
-                }
-
-                // h264
-                return string.Format(" -b:v {0} -maxrate {0} -bufsize {1}",
-                    bitrate.Value.ToString(UsCulture),
-                    (bitrate.Value * 2).ToString(UsCulture));
-            }
-
-            return string.Empty;
-        }
-
-        protected double? GetFramerateParam(EncodingJob state)
-        {
-            if (state.Options != null)
-            {
-                if (state.Options.Framerate.HasValue)
-                {
-                    return state.Options.Framerate.Value;
-                }
-
-                var maxrate = state.Options.MaxFramerate;
-
-                if (maxrate.HasValue && state.VideoStream != null)
-                {
-                    var contentRate = state.VideoStream.AverageFrameRate ?? state.VideoStream.RealFrameRate;
-
-                    if (contentRate.HasValue && contentRate.Value > maxrate.Value)
-                    {
-                        return maxrate;
-                    }
-                }
-            }
-
-            return null;
-        }
-
-        /// <summary>
-        /// Gets the map args.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <returns>System.String.</returns>
-        protected virtual string GetMapArgs(EncodingJob state)
-        {
-            // If we don't have known media info
-            // If input is video, use -sn to drop subtitles
-            // Otherwise just return empty
-            if (state.VideoStream == null && state.AudioStream == null)
-            {
-                return state.IsInputVideo ? "-sn" : string.Empty;
-            }
-
-            // We have media info, but we don't know the stream indexes
-            if (state.VideoStream != null && state.VideoStream.Index == -1)
-            {
-                return "-sn";
-            }
-
-            // We have media info, but we don't know the stream indexes
-            if (state.AudioStream != null && state.AudioStream.Index == -1)
-            {
-                return state.IsInputVideo ? "-sn" : string.Empty;
-            }
-
-            var args = string.Empty;
-
-            if (state.VideoStream != null)
-            {
-                args += string.Format("-map 0:{0}", state.VideoStream.Index);
-            }
-            else
-            {
-                // No known video stream
-                args += "-vn";
-            }
-
-            if (state.AudioStream != null)
-            {
-                args += string.Format(" -map 0:{0}", state.AudioStream.Index);
-            }
-
-            else
-            {
-                args += " -map -0:a";
-            }
-
-            if (state.SubtitleStream == null || state.Options.SubtitleMethod == SubtitleDeliveryMethod.Hls)
-            {
-                args += " -map -0:s";
-            }
-            else if (state.SubtitleStream.IsExternal && !state.SubtitleStream.IsTextSubtitleStream)
-            {
-                args += " -map 1:0 -sn";
-            }
-
-            return args;
-        }
-
-        /// <summary>
-        /// Determines whether the specified stream is H264.
-        /// </summary>
-        /// <param name="stream">The stream.</param>
-        /// <returns><c>true</c> if the specified stream is H264; otherwise, <c>false</c>.</returns>
-        protected bool IsH264(MediaStream stream)
-        {
-            var codec = stream.Codec ?? string.Empty;
-
-            return codec.IndexOf("264", StringComparison.OrdinalIgnoreCase) != -1 ||
-                   codec.IndexOf("avc", StringComparison.OrdinalIgnoreCase) != -1;
-        }
-
-        /// <summary>
-        /// If we're going to put a fixed size on the command line, this will calculate it
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <param name="outputVideoCodec">The output video codec.</param>
-        /// <param name="allowTimeStampCopy">if set to <c>true</c> [allow time stamp copy].</param>
-        /// <returns>System.String.</returns>
-        protected async Task<string> GetOutputSizeParam(EncodingJob state,
-            string outputVideoCodec,
-            bool allowTimeStampCopy = true)
-        {
-            // http://sonnati.wordpress.com/2012/10/19/ffmpeg-the-swiss-army-knife-of-internet-streaming-part-vi/
-
-            var request = state.Options;
-
-            var filters = new List<string>();
-
-            if (string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-            {
-                filters.Add("format=nv12|vaapi");
-                filters.Add("hwupload");
-            }
-            else if (state.DeInterlace && !string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-            {
-                filters.Add("yadif=0:-1:0");
-            }
-
-            if (string.Equals(outputVideoCodec, "h264_vaapi", StringComparison.OrdinalIgnoreCase))
-            {
-                // Work around vaapi's reduced scaling features
-                var scaler = "scale_vaapi";
-
-                // Given the input dimensions (inputWidth, inputHeight), determine the output dimensions
-                // (outputWidth, outputHeight). The user may request precise output dimensions or maximum
-                // output dimensions. Output dimensions are guaranteed to be even.
-                decimal inputWidth = Convert.ToDecimal(state.VideoStream.Width);
-                decimal inputHeight = Convert.ToDecimal(state.VideoStream.Height);
-                decimal outputWidth = request.Width.HasValue ? Convert.ToDecimal(request.Width.Value) : inputWidth;
-                decimal outputHeight = request.Height.HasValue ? Convert.ToDecimal(request.Height.Value) : inputHeight;
-                decimal maximumWidth = request.MaxWidth.HasValue ? Convert.ToDecimal(request.MaxWidth.Value) : outputWidth;
-                decimal maximumHeight = request.MaxHeight.HasValue ? Convert.ToDecimal(request.MaxHeight.Value) : outputHeight;
-
-                if (outputWidth > maximumWidth || outputHeight > maximumHeight)
-                {
-                    var scale = Math.Min(maximumWidth / outputWidth, maximumHeight / outputHeight);
-                    outputWidth = Math.Min(maximumWidth, Math.Truncate(outputWidth * scale));
-                    outputHeight = Math.Min(maximumHeight, Math.Truncate(outputHeight * scale));
-                }
-
-                outputWidth = 2 * Math.Truncate(outputWidth / 2);
-                outputHeight = 2 * Math.Truncate(outputHeight / 2);
-
-                if (outputWidth != inputWidth || outputHeight != inputHeight)
-                {
-                    filters.Add(string.Format("{0}=w={1}:h={2}", scaler, outputWidth.ToString(UsCulture), outputHeight.ToString(UsCulture)));
-                }
-            }
-            else
-            {
-                // If fixed dimensions were supplied
-                if (request.Width.HasValue && request.Height.HasValue)
-                {
-                    var widthParam = request.Width.Value.ToString(UsCulture);
-                    var heightParam = request.Height.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale=trunc({0}/2)*2:trunc({1}/2)*2", widthParam, heightParam));
-                }
-
-                // If Max dimensions were supplied, for width selects lowest even number between input width and width req size and selects lowest even number from in width*display aspect and requested size
-                else if (request.MaxWidth.HasValue && request.MaxHeight.HasValue)
-                {
-                    var maxWidthParam = request.MaxWidth.Value.ToString(UsCulture);
-                    var maxHeightParam = request.MaxHeight.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale=trunc(min(max(iw\\,ih*dar)\\,min({0}\\,{1}*dar))/2)*2:trunc(min(max(iw/dar\\,ih)\\,min({0}/dar\\,{1}))/2)*2", maxWidthParam, maxHeightParam));
-                }
-
-                // If a fixed width was requested
-                else if (request.Width.HasValue)
-                {
-                    var widthParam = request.Width.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale={0}:trunc(ow/a/2)*2", widthParam));
-                }
-
-                // If a fixed height was requested
-                else if (request.Height.HasValue)
-                {
-                    var heightParam = request.Height.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale=trunc(oh*a/2)*2:{0}", heightParam));
-                }
-
-                // If a max width was requested
-                else if (request.MaxWidth.HasValue)
-                {
-                    var maxWidthParam = request.MaxWidth.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale=trunc(min(max(iw\\,ih*dar)\\,{0})/2)*2:trunc(ow/dar/2)*2", maxWidthParam));
-                }
-
-                // If a max height was requested
-                else if (request.MaxHeight.HasValue)
-                {
-                    var maxHeightParam = request.MaxHeight.Value.ToString(UsCulture);
-
-                    filters.Add(string.Format("scale=trunc(oh*a/2)*2:min(max(iw/dar\\,ih)\\,{0})", maxHeightParam));
-                }
-            }
-
-            var output = string.Empty;
-
-            if (state.SubtitleStream != null && state.SubtitleStream.IsTextSubtitleStream && state.Options.SubtitleMethod == SubtitleDeliveryMethod.Encode)
-            {
-                var subParam = await GetTextSubtitleParam(state).ConfigureAwait(false);
-
-                filters.Add(subParam);
-
-                if (allowTimeStampCopy)
-                {
-                    output += " -copyts";
-                }
-            }
-
-            if (filters.Count > 0)
-            {
-                output += string.Format(" -vf \"{0}\"", string.Join(",", filters.ToArray()));
-            }
-
-            return output;
-        }
-
-        /// <summary>
-        /// Gets the text subtitle param.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        /// <returns>System.String.</returns>
-        protected async Task<string> GetTextSubtitleParam(EncodingJob state)
-        {
-            var seconds = Math.Round(TimeSpan.FromTicks(state.Options.StartTimeTicks ?? 0).TotalSeconds);
-
-            if (state.SubtitleStream.IsExternal)
-            {
-                var subtitlePath = state.SubtitleStream.Path;
-
-                var charsetParam = string.Empty;
-
-                if (!string.IsNullOrEmpty(state.SubtitleStream.Language))
-                {
-                    var charenc = await SubtitleEncoder.GetSubtitleFileCharacterSet(subtitlePath, state.SubtitleStream.Language, state.MediaSource.Protocol, CancellationToken.None).ConfigureAwait(false);
-
-                    if (!string.IsNullOrEmpty(charenc))
-                    {
-                        charsetParam = ":charenc=" + charenc;
-                    }
-                }
-
-                // TODO: Perhaps also use original_size=1920x800 ??
-                return string.Format("subtitles=filename='{0}'{1},setpts=PTS -{2}/TB",
-                    MediaEncoder.EscapeSubtitleFilterPath(subtitlePath),
-                    charsetParam,
-                    seconds.ToString(UsCulture));
-            }
-
-            var mediaPath = state.MediaPath ?? string.Empty;
-
-            return string.Format("subtitles='{0}:si={1}',setpts=PTS -{2}/TB",
-                MediaEncoder.EscapeSubtitleFilterPath(mediaPath),
-                state.InternalSubtitleStreamOffset.ToString(UsCulture),
-                seconds.ToString(UsCulture));
-        }
-
-        protected string GetAudioFilterParam(EncodingJob state, bool isHls)
-        {
-            var volParam = string.Empty;
-            var audioSampleRate = string.Empty;
-
-            var channels = state.OutputAudioChannels;
-
-            // Boost volume to 200% when downsampling from 6ch to 2ch
-            if (channels.HasValue && channels.Value <= 2)
-            {
-                if (state.AudioStream != null && state.AudioStream.Channels.HasValue && state.AudioStream.Channels.Value > 5 && !GetEncodingOptions().DownMixAudioBoost.Equals(1))
-                {
-                    volParam = ",volume=" + GetEncodingOptions().DownMixAudioBoost.ToString(UsCulture);
-                }
-            }
-
-            if (state.OutputAudioSampleRate.HasValue)
-            {
-                audioSampleRate = state.OutputAudioSampleRate.Value + ":";
-            }
-
-            var adelay = isHls ? "adelay=1," : string.Empty;
-
-            var pts = string.Empty;
-
-            if (state.SubtitleStream != null && state.SubtitleStream.IsTextSubtitleStream && state.Options.SubtitleMethod == SubtitleDeliveryMethod.Encode && !state.Options.CopyTimestamps)
-            {
-                var seconds = TimeSpan.FromTicks(state.Options.StartTimeTicks ?? 0).TotalSeconds;
-
-                pts = string.Format(",asetpts=PTS-{0}/TB", Math.Round(seconds).ToString(UsCulture));
-            }
-
-            return string.Format("-af \"{0}aresample={1}async={4}{2}{3}\"",
-
-                adelay,
-                audioSampleRate,
-                volParam,
-                pts,
-                state.OutputAudioSync);
-        }
     }
 }