change framerate normalization method (#611)

ErsatzTV.Core/FFmpeg/FFmpegComplexFilterBuilder.cs

@@ -28,7 +28,6 @@ namespace ErsatzTV.Core.FFmpeg
         private string _videoEncoder;
         private Option<string> _subtitle;
         private bool _boxBlur;
-        private Option<int> _frameRate;
 
         public FFmpegComplexFilterBuilder WithHardwareAcceleration(HardwareAccelerationKind hardwareAccelerationKind)
         {
@@ -86,12 +85,6 @@ namespace ErsatzTV.Core.FFmpeg
             return this;
         }
 
-        public FFmpegComplexFilterBuilder WithFrameRate(Option<int> frameRate)
-        {
-            _frameRate = frameRate;
-            return this;
-        }
-
         public FFmpegComplexFilterBuilder WithWatermark(
             Option<ChannelWatermark> watermark,
             Option<List<FadePoint>> maybeFadePoints,
@@ -247,8 +240,6 @@ namespace ErsatzTV.Core.FFmpeg
                 videoFilterQueue.Add("format=nv12|vaapi,hwupload");
             }
 
-            videoFilterQueue.AddRange(_frameRate.Select(frameRate => $"fps=fps={frameRate}"));
-
             _scaleToSize.IfSome(
                 size =>
                 {

ErsatzTV.Core/FFmpeg/FFmpegProcessBuilder.cs

@@ -216,7 +216,15 @@ namespace ErsatzTV.Core.FFmpeg
 
         public FFmpegProcessBuilder WithFrameRate(Option<int> frameRate)
         {
-            _complexFilterBuilder = _complexFilterBuilder.WithFrameRate(frameRate);
+            foreach (int fr in frameRate)
+            {
+                _arguments.Add("-r");
+                _arguments.Add($"{fr}");
+            
+                _arguments.Add("-vsync");
+                _arguments.Add("1");
+            }
+
             return this;
         }