Codec selection (#892)

* Query for installed codecs

* Start modeling out codecs

* Can now specify a codec and get the correct settings returned from the model

* Return codecs in admin/serverconfig

* Start handling transcoding errors and return messages to user

* filter available codecs against a whitelist

* Fix merge

* Codecs are working

* Switching between codecs work

* Add apis for setting a custom video codec

* Cleanup the logging of transcoder errors

* Add v4l codec

* Add fetching v4l

* Add support for per-codec presets

* Use updated nvenc encoding parameters

* Update log message

* Some more codec WIP

* Turn off v4l. It is a mess.

* Try to make the lowest latency level a bit more playable

* Use a human redable display name in console messages

* Turn on transcoder persistent connections

* Add more codec-related user-facing error messages

* Give the initial offline state transcoder an id

* Force a minimum segment count of 3

* Disable qsv for now. set x264 specific params in VariantFlags

* Close body in case

* Ignore vbv underflow message, it is not actionable

* Determine a dynamic gop value based on the length of segments

* Add codec-specific tests

* Cleanup

* Ignore goconst lint warnings in codec file

* Troubleshoot omx

* Add more codec tests

* Remove no longer accurate comment

* Bundle admin from codec branch

* Revert back to old setting

* Cleanup list of codecs a bit

* Remove old references to the encoder preset

* Commit updated API documentation

* Update admin bundle

* Commit updated API documentation

* Add codec setting to api spec

* Commit updated API documentation

Co-authored-by: Owncast <owncast@owncast.online>

controllers/admin/config.go

@@ -438,26 +438,6 @@ func SetStreamOutputVariants(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// Temporary: Convert the cpuUsageLevel to a preset.  In the future we will have
-	// different codec models that will handle this for us and we won't
-	// be keeping track of presets at all.  But for now...
-	presetMapping := []string{
-		"ultrafast",
-		"superfast",
-		"veryfast",
-		"faster",
-		"fast",
-	}
-
-	for i, variant := range videoVariants.Value {
-		preset := "superfast"
-		if variant.CPUUsageLevel > 0 && variant.CPUUsageLevel <= len(presetMapping) {
-			preset = presetMapping[variant.CPUUsageLevel-1]
-		}
-		variant.EncoderPreset = preset
-		videoVariants.Value[i] = variant
-	}
-
 	if err := data.SetStreamOutputVariants(videoVariants.Value); err != nil {
 		controllers.WriteSimpleResponse(w, false, "unable to update video config with provided values "+err.Error())
 		return
@@ -508,6 +488,26 @@ func SetChatDisabled(w http.ResponseWriter, r *http.Request) {
 	controllers.WriteSimpleResponse(w, true, "chat disabled status updated")
 }
 
+// SetVideoCodec will change the codec used for video encoding.
+func SetVideoCodec(w http.ResponseWriter, r *http.Request) {
+	if !requirePOST(w, r) {
+		return
+	}
+
+	configValue, success := getValueFromRequest(w, r)
+	if !success {
+		controllers.WriteSimpleResponse(w, false, "unable to change video codec")
+		return
+	}
+
+	if err := data.SetVideoCodec(configValue.Value.(string)); err != nil {
+		controllers.WriteSimpleResponse(w, false, "unable to update codec")
+		return
+	}
+
+	controllers.WriteSimpleResponse(w, true, "video codec updated")
+}
+
 // SetExternalActions will set the 3rd party actions for the web interface.
 func SetExternalActions(w http.ResponseWriter, r *http.Request) {
 	type externalActionsRequest struct {

controllers/admin/serverConfig.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/owncast/owncast/config"
 	"github.com/owncast/owncast/core/data"
+	"github.com/owncast/owncast/core/transcoder"
 	"github.com/owncast/owncast/models"
 	"github.com/owncast/owncast/utils"
 	log "github.com/sirupsen/logrus"
@@ -13,6 +14,8 @@ import (
 
 // GetServerConfig gets the config details of the server.
 func GetServerConfig(w http.ResponseWriter, r *http.Request) {
+	ffmpeg := utils.ValidatedFfmpegPath(data.GetFfMpegPath())
+
 	var videoQualityVariants = make([]models.StreamOutputVariant, 0)
 	for _, variant := range data.GetStreamOutputVariants() {
 		videoQualityVariants = append(videoQualityVariants, models.StreamOutputVariant{
@@ -20,10 +23,9 @@ func GetServerConfig(w http.ResponseWriter, r *http.Request) {
 			IsAudioPassthrough: variant.GetIsAudioPassthrough(),
 			IsVideoPassthrough: variant.IsVideoPassthrough,
 			Framerate:          variant.GetFramerate(),
-			EncoderPreset:      variant.GetEncoderPreset(),
 			VideoBitrate:       variant.VideoBitrate,
 			AudioBitrate:       variant.AudioBitrate,
-			CPUUsageLevel:      variant.GetCPUUsageLevel(),
+			CPUUsageLevel:      variant.CPUUsageLevel,
 			ScaledWidth:        variant.ScaledWidth,
 			ScaledHeight:       variant.ScaledHeight,
 		})
@@ -41,7 +43,7 @@ func GetServerConfig(w http.ResponseWriter, r *http.Request) {
 			NSFW:             data.GetNSFW(),
 			CustomStyles:     data.GetCustomStyles(),
 		},
-		FFmpegPath:     utils.ValidatedFfmpegPath(data.GetFfMpegPath()),
+		FFmpegPath:     ffmpeg,
 		StreamKey:      data.GetStreamKey(),
 		WebServerPort:  config.WebServerPort,
 		RTMPServerPort: data.GetRTMPPortNumber(),
@@ -56,6 +58,8 @@ func GetServerConfig(w http.ResponseWriter, r *http.Request) {
 		},
 		S3:              data.GetS3Config(),
 		ExternalActions: data.GetExternalActions(),
+		SupportedCodecs: transcoder.GetCodecs(ffmpeg),
+		VideoCodec:      data.GetVideoCodec(),
 	}
 
 	w.Header().Set("Content-Type", "application/json")
@@ -77,6 +81,8 @@ type serverConfigAdminResponse struct {
 	YP              yp                      `json:"yp"`
 	ChatDisabled    bool                    `json:"chatDisabled"`
 	ExternalActions []models.ExternalAction `json:"externalActions"`
+	SupportedCodecs []string                `json:"supportedCodecs"`
+	VideoCodec      string                  `json:"videoCodec"`
 }
 
 type videoSettings struct {