Add support for custom encoder presets

config.go

@@ -23,6 +23,7 @@ type Config struct {
 type VideoSettings struct {
 	ChunkLengthInSeconds int             `yaml:"chunkLengthInSeconds"`
 	StreamingKey         string          `yaml:"streamingKey"`
+	EncoderPreset        string          `yaml:"encoderPreset"`
 	StreamQualities      []StreamQuality `yaml:"streamQualities"`
 }
 
@@ -85,4 +86,12 @@ func checkConfig(config Config) {
 	if !fileExists(config.FFMpegPath) {
 		panic(fmt.Sprintf("ffmpeg does not exist at %s.", config.FFMpegPath))
 	}
+
+	if config.VideoSettings.EncoderPreset == "" {
+		panic("A video encoder preset is required to be set in the config file.")
+	}
+
+	if len(config.VideoSettings.StreamQualities) < 1 {
+		panic("At least one stream quality must be set in the config file.")
+	}
 }

config/config-example.yaml

@@ -6,6 +6,7 @@ webServerPort: 8080
 videoSettings:
   chunkLengthInSeconds: 4
   streamingKey: abc123
+  encoderPreset: superfast # https://trac.ffmpeg.org/wiki/Encode/H.264
 
   streamQualities:
     - bitrate: 6000k

ffmpeg.go

@@ -48,7 +48,7 @@ func startFfmpeg(configuration Config) {
 		"-master_pl_name stream.m3u8",
 		"-g 48",
 		"-keyint_min 48",
-		"-preset superfast",
+		"-preset " + configuration.VideoSettings.EncoderPreset,
 		"-sc_threshold 0",
 		"-profile:v high",
 		"-f hls",