Enable mjpeg_videotoolbox for trickplay

Signed-off-by: gnattu <gnattuoc@me.com>

MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs

@@ -118,7 +118,8 @@ namespace MediaBrowser.Controller.MediaEncoding
         private static readonly Dictionary<string, string> _mjpegCodecMap = new(StringComparer.OrdinalIgnoreCase)
         {
             { "vaapi", _defaultMjpegEncoder + "_vaapi" },
-            { "qsv", _defaultMjpegEncoder + "_qsv" }
+            { "qsv", _defaultMjpegEncoder + "_qsv" },
+            { "videotoolbox", _defaultMjpegEncoder + "_videotoolbox" }
         };
 
         public static readonly string[] LosslessAudioCodecs = new string[]

MediaBrowser.MediaEncoding/Encoder/EncoderValidator.cs

@@ -94,6 +94,7 @@ namespace MediaBrowser.MediaEncoding.Encoder
             "h264_v4l2m2m",
             "h264_videotoolbox",
             "hevc_videotoolbox",
+            "mjpeg_videotoolbox",
             "h264_rkmpp",
             "hevc_rkmpp"
         };

MediaBrowser.MediaEncoding/Encoder/MediaEncoder.cs

@@ -871,6 +871,16 @@ namespace MediaBrowser.MediaEncoding.Encoder
                 throw new InvalidOperationException("Empty or invalid input argument.");
             }
 
+            var encoderQuality = qualityScale;
+            if (vidEncoder.Contains("videotoolbox", StringComparison.InvariantCultureIgnoreCase))
+            {
+                // videotoolbox's mjpeg encoder uses jpeg quality instead of ffmpeg defined qscale
+                // ffmpeg qscale is a value from 1-31, with 1 being best quality and 31 being worst
+                // jpeg quality is a value from 0-100, with 0 being worst quality and 100 being best
+                // This mapping is just an estimation, with bias towards higher quality
+                encoderQuality = 100 - ((qualityScale - 1) * 3);
+            }
+
             // Output arguments
             var targetDirectory = Path.Combine(_configurationManager.ApplicationPaths.TempDirectory, Guid.NewGuid().ToString("N"));
             Directory.CreateDirectory(targetDirectory);
@@ -879,12 +889,13 @@ namespace MediaBrowser.MediaEncoding.Encoder
             // Final command arguments
             var args = string.Format(
                 CultureInfo.InvariantCulture,
-                "-loglevel error {0} -an -sn {1} -threads {2} -c:v {3} {4}-f {5} \"{6}\"",
+                "-loglevel error {0} -an -sn {1} -threads {2} -c:v {3} {4}{5}-f {6} \"{7}\"",
                 inputArg,
                 filterParam,
                 outputThreads.GetValueOrDefault(_threads),
                 vidEncoder,
-                qualityScale.HasValue ? "-qscale:v " + qualityScale.Value.ToString(CultureInfo.InvariantCulture) + " " : string.Empty,
+                qualityScale.HasValue ? "-qscale:v " + encoderQuality.Value.ToString(CultureInfo.InvariantCulture) + " " : string.Empty,
+                vidEncoder.Contains("videotoolbox", StringComparison.InvariantCultureIgnoreCase) ? "-allow_sw 1 " : string.Empty, // allow_sw fallback for some intel macs
                 "image2",
                 outputPath);