add video config evaluation.

go.mod

@@ -3,6 +3,7 @@ module demodesk/neko
 go 1.16
 
 require (
+	github.com/PaesslerAG/gval v1.1.0 // indirect
 	github.com/go-chi/chi v1.5.4
 	github.com/go-chi/cors v1.1.1
 	github.com/google/uuid v1.2.0 // indirect

go.sum

@@ -14,6 +14,9 @@ dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
+github.com/PaesslerAG/gval v1.1.0 h1:k3RuxeZDO3eejD4cMPSt+74tUSvTnbGvLx0df4mdwFc=
+github.com/PaesslerAG/gval v1.1.0/go.mod h1:y/nm5yEyTeX6av0OfKJNp9rBNj2XrGhAf5+v24IBN1I=
+github.com/PaesslerAG/jsonpath v0.1.0/go.mod h1:4BzmtoM/PI8fPO4aQGIusjGxGir2BzcV0grWtFzq1Y8=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=

internal/capture/manager.go

@@ -8,7 +8,6 @@ import (
 
 	"demodesk/neko/internal/config"
 	"demodesk/neko/internal/types"
-	"demodesk/neko/internal/types/codec"
 )
 
 type CaptureManagerCtx struct {
@@ -56,6 +55,37 @@ func New(desktop types.DesktopManager, config *config.Capture) *CaptureManagerCt
 		)
 	}
 
+	videos := map[string]*StreamManagerCtx{}
+	videoIDs := []string{}
+	for key, pipelineConf := range config.Video {
+		codec, err := pipelineConf.GetCodec()
+		if err != nil {
+			logger.Panic().Err(err).Str("video_key", key).Msg("unable to get video codec")
+		}
+
+		createPipeline := func() string {
+			screen := desktop.GetScreenSize()
+
+			pipeline, err := pipelineConf.GetPipeline(*screen)
+			if err != nil {
+				logger.Panic().Err(err).Str("video_key", key).Msg("unable to get video pipeline")
+			}
+
+			return fmt.Sprintf(
+				"ximagesrc display-name=%s show-pointer=false use-damage=false "+
+					"! %s "+
+					"! appsink name=appsink", config.Display, pipeline,
+			)
+		}
+
+		// trigger function to catch evaluation errors at startup
+		_ = createPipeline()
+
+		// append to videos
+		videos[key] = streamNew(codec, createPipeline)
+		videoIDs = append(videoIDs, key)
+	}
+
 	return &CaptureManagerCtx{
 		logger:     logger,
 		desktop:    desktop,
@@ -76,65 +106,8 @@ func New(desktop types.DesktopManager, config *config.Capture) *CaptureManagerCt
 					"! appsink name=appsink", config.AudioDevice, config.AudioCodec.Pipeline,
 			)
 		}),
-		videos: map[string]*StreamManagerCtx{
+		videos:   videos,
-			"hd": streamNew(codec.VP8(), func() string {
+		videoIDs: videoIDs,
-				screen := desktop.GetScreenSize()
-				bitrate := int((screen.Width * screen.Height * 6) / 4)
-				buffer := bitrate / 1000
-
-				return fmt.Sprintf(
-					"ximagesrc display-name=%s show-pointer=false use-damage=false "+
-						"! video/x-raw,framerate=25/1 "+
-						"! videoconvert "+
-						"! queue "+
-						"! vp8enc end-usage=cbr target-bitrate=%d cpu-used=4 threads=4 deadline=1 undershoot=95 keyframe-max-dist=25 min-quantizer=3 max-quantizer=32 buffer-size=%d buffer-initial-size=%d buffer-optimal-size=%d "+
-						"! appsink name=appsink", config.Display, bitrate, buffer*6, buffer*4, buffer*5,
-				)
-			}),
-			"hq": streamNew(codec.VP8(), func() string {
-				screen := desktop.GetScreenSize()
-				bitrate := int((screen.Width * screen.Height * 6) / 4) / 2
-				buffer := bitrate / 1000
-
-				return fmt.Sprintf(
-					"ximagesrc display-name=%s show-pointer=false use-damage=false "+
-						"! video/x-raw,framerate=15/1 "+
-						"! videoconvert "+
-						"! queue "+
-						"! vp8enc end-usage=cbr target-bitrate=%d cpu-used=4 threads=4 deadline=1 undershoot=95 keyframe-max-dist=25 min-quantizer=3 max-quantizer=32 buffer-size=%d buffer-initial-size=%d buffer-optimal-size=%d "+
-						"! appsink name=appsink", config.Display, bitrate, buffer*6, buffer*4, buffer*5,
-				)
-			}),
-			"mq": streamNew(codec.VP8(), func() string {
-				screen := desktop.GetScreenSize()
-				bitrate := int((screen.Width * screen.Height * 6) / 4) / 3
-				buffer := bitrate / 1000
-
-				return fmt.Sprintf(
-					"ximagesrc display-name=%s show-pointer=false use-damage=false "+
-						"! video/x-raw,framerate=10/1 "+
-						"! videoconvert "+
-						"! queue "+
-						"! vp8enc end-usage=cbr target-bitrate=%d cpu-used=4 threads=4 deadline=1 undershoot=95 keyframe-max-dist=25 min-quantizer=3 max-quantizer=32 buffer-size=%d buffer-initial-size=%d buffer-optimal-size=%d "+
-						"! appsink name=appsink", config.Display, bitrate, buffer*6, buffer*4, buffer*5,
-				)
-			}),
-			"lq": streamNew(codec.VP8(), func() string {
-				screen := desktop.GetScreenSize()
-				bitrate := int((screen.Width * screen.Height * 6) / 4) / 4
-				buffer := bitrate / 1000
-	
-				return fmt.Sprintf(
-					"ximagesrc display-name=%s show-pointer=false use-damage=false "+
-						"! video/x-raw,framerate=5/1 "+
-						"! videoconvert "+
-						"! queue "+
-						"! vp8enc end-usage=cbr target-bitrate=%d cpu-used=4 threads=4 deadline=1 undershoot=95 keyframe-max-dist=25 min-quantizer=3 max-quantizer=32 buffer-size=%d buffer-initial-size=%d buffer-optimal-size=%d "+
-						"! appsink name=appsink", config.Display, bitrate, buffer*6, buffer*4, buffer*5,
-				)
-			}),
-		},
-		videoIDs: []string{"hd", "hq", "mq", "lq"},
 	}
 }
 

internal/config/capture.go

@@ -7,12 +7,16 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 
+	"demodesk/neko/internal/types"
 	"demodesk/neko/internal/types/codec"
+	"demodesk/neko/internal/utils"
 )
 
 type Capture struct {
 	Display string
 
+	Video map[string] types.VideoConfig
+
 	AudioDevice   string
 	AudioCodec    codec.RTPCodec
 	AudioPipeline string
@@ -94,6 +98,14 @@ func (s *Capture) Set() {
 	// Display is provided by env variable
 	s.Display = os.Getenv("DISPLAY")
 
+	// video
+	if err := viper.UnmarshalKey("capture.video", &s.Video, viper.DecodeHook(
+		utils.JsonStringAutoDecode(s.Video),
+	)); err != nil {
+		log.Warn().Err(err).Msgf("unable to parse video settings")
+	}
+
+	// audio
 	s.AudioDevice = viper.GetString("capture.audio.device")
 	s.AudioPipeline = viper.GetString("capture.audio.pipeline")
 
@@ -112,11 +124,13 @@ func (s *Capture) Set() {
 		s.AudioCodec = codec.Opus()
 	}
 
+	// broadcast
 	s.BroadcastAudioBitrate = viper.GetInt("capture.broadcast.audio_bitrate")
 	s.BroadcastVideoBitrate = viper.GetInt("capture.broadcast.video_bitrate")
 	s.BroadcastPreset = viper.GetString("capture.broadcast.preset")
 	s.BroadcastPipeline = viper.GetString("capture.broadcast.pipeline")
 
+	// screencast
 	s.ScreencastEnabled = viper.GetBool("capture.screencast.enabled")
 	s.ScreencastRate = viper.GetString("capture.screencast.rate")
 	s.ScreencastQuality = viper.GetString("capture.screencast.quality")

internal/types/capture.go

@@ -1,7 +1,12 @@
 package types
 
 import (
+	"math"
+	"strings"
+	"fmt"
+
 	"github.com/pion/webrtc/v3/pkg/media"
+	"github.com/PaesslerAG/gval"
 
 	"demodesk/neko/internal/types/codec"
 )
@@ -43,3 +48,98 @@ type CaptureManager interface {
 	Video(videoID string) (StreamManager, bool)
 	VideoIDs() []string
 }
+
+type VideoConfig struct {
+	Codec       string            `mapstructure:"codec"`
+	Width       string            `mapstructure:"width"`        // expression
+	Height      string            `mapstructure:"height"`       // expression
+	Fps         string            `mapstructure:"fps"`          // expression
+	GstEncoder  string            `mapstructure:"gst_encoder"`
+	GstParams   map[string]string `mapstructure:"gst_params"`   // map of expressions
+	GstPipeline string            `mapstructure:"gst_pipeline"`
+}
+
+func (config *VideoConfig) GetCodec() (codec.RTPCodec, error) {
+	switch strings.ToLower(config.Codec) {
+	case "vp8":
+		return codec.VP8(), nil
+	case "vp9":
+		return codec.VP9(), nil
+	case "h264":
+		return codec.H264(), nil
+	default:
+		return codec.RTPCodec{}, fmt.Errorf("unknown codec")
+	}
+}
+
+func (config *VideoConfig) GetPipeline(screen ScreenSize) (string, error) {
+	if config.GstPipeline != "" {
+		return config.GstPipeline, nil
+	}
+
+	values := map[string]interface{}{
+		"width":  screen.Width,
+		"height": screen.Height,
+		"fps":    screen.Rate,
+	}
+
+	language := []gval.Language{
+		gval.Function("round", func(args ...interface{}) (interface{}, error) {
+			return (int)(math.Round(args[0].(float64))), nil
+		}),
+	}
+
+	// get fps pipeline
+	fpsPipeline := "video/x-raw ! videoconvert ! queue"
+	if config.Fps != "" {
+		var err error
+		val, err := gval.Evaluate(config.Fps, values, language...)
+		if err != nil {
+			return "", err
+		}
+	
+		if val != nil {
+			// TODO: To fraction.
+			fpsPipeline = fmt.Sprintf("video/x-raw,framerate=%v ! videoconvert ! queue", val)
+		}
+	}
+
+	// get scale pipeline
+	scalePipeline := ""
+	if config.Width != "" && config.Height != "" {
+		w, err := gval.Evaluate(config.Width, values, language...)
+		if err != nil {
+			return "", err
+		}
+
+		h, err := gval.Evaluate(config.Height, values, language...)
+		if err != nil {
+			return "", err
+		}
+
+		if w != nil && h != nil {
+			scalePipeline = fmt.Sprintf("! videoscale ! video/x-raw,width=%v,height=%v ! queue", w, h)
+		}
+	}
+
+	// get encoder pipeline
+	encPipeline := fmt.Sprintf("! %s", config.GstEncoder)
+	for key, expr := range config.GstParams {
+		if expr == "" {
+			continue
+		}
+
+		val, err := gval.Evaluate(expr, values, language...)
+		if err != nil {
+			return "", err
+		}
+
+		if val != nil {
+			encPipeline += fmt.Sprintf(" %s=%v", key, val)
+		} else {
+			encPipeline += fmt.Sprintf(" %s=%s", key, expr)
+		}
+	}
+
+	return fmt.Sprintf("%s %s %s", fpsPipeline, scalePipeline, encPipeline), nil
+}