transcoding

encoder.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"log"
+
+	"github.com/asticode/go-astiav"
+	"github.com/asticode/go-astikit"
+)
+
+type EncoderStream struct {
+	encCodec        *astiav.Codec
+	encCodecContext *astiav.CodecContext
+	encPkt          *astiav.Packet
+}
+
+type Encoder struct {
+	Stream *EncoderStream
+	Closer *astikit.Closer
+}
+
+type EncoderParams struct {
+	Height      int
+	Width       int
+	TimeBase    astiav.Rational
+	AspectRatio astiav.Rational
+	PixelFormat astiav.PixelFormat
+}
+
+func NewEncoder(params EncoderParams) (ts *Encoder, err error) {
+	ts = &Encoder{}
+	s := &EncoderStream{}
+	c := astikit.NewCloser()
+	ts.Closer = c
+	ts.Stream = s
+
+	// Get codec id
+	codecID := astiav.CodecIDMpeg4
+
+	// Find encoder
+	if s.encCodec = astiav.FindEncoder(codecID); s.encCodec == nil {
+		err = errors.New("main: codec is nil")
+		return
+	}
+
+	// Alloc codec context
+	if s.encCodecContext = astiav.AllocCodecContext(s.encCodec); s.encCodecContext == nil {
+		err = errors.New("main: codec context is nil")
+		return
+	}
+	c.Add(s.encCodecContext.Free)
+
+	s.encCodecContext.SetHeight(params.Height)
+	s.encCodecContext.SetPixelFormat(params.PixelFormat)
+	s.encCodecContext.SetBitRate(1000)
+	s.encCodecContext.SetSampleAspectRatio(params.AspectRatio)
+	s.encCodecContext.SetTimeBase(params.TimeBase)
+	s.encCodecContext.SetWidth(params.Width)
+
+	// Open codec context
+	if err = s.encCodecContext.Open(s.encCodec, nil); err != nil {
+		err = fmt.Errorf("encoder: opening codec context failed: %w", err)
+		return
+	}
+
+	// Allocate packet
+	s.encPkt = astiav.AllocPacket()
+	c.Add(s.encPkt.Free)
+
+	return ts, nil
+}
+
+func (ts *Encoder) Close() {
+	ts.Closer.Close()
+}
+
+func (ts *Encoder) Encode(f *astiav.Frame) (pkt *astiav.Packet, err error) {
+	s := ts.Stream
+
+	// Unref packet
+	s.encPkt.Unref()
+
+	log.Println(len(f.Data()))
+
+	// Send frame
+	if err = s.encCodecContext.SendFrame(f); err != nil {
+		err = fmt.Errorf("encoder: sending frame failed: %w", err)
+		return nil, err
+	}
+
+	if err := s.encCodecContext.ReceivePacket(s.encPkt); err != nil {
+		log.Fatal(fmt.Errorf("encoder: receiving frame failed: %w", err))
+		return nil, err
+	}
+
+	return s.encPkt, nil
+}

main.go

@@ -58,29 +58,52 @@ func ReplaceTrack(prefix string, peerConnection *webrtc.PeerConnection) {
 				log.Println(fmt.Errorf("main: peer connection closed due to error: %w", err))
 			}
 		} else if connectionState.String() == "connected" {
-			astiav.SetLogLevel(astiav.LogLevelDebug)
+			astiav.SetLogLevel(astiav.LogLevelError)
 			astiav.SetLogCallback(func(l astiav.LogLevel, fmt, msg, parent string) {
 				log.Printf("ffmpeg log: %s (level: %d)\n", strings.TrimSpace(msg), l)
 			})
 			go func() {
+				encoderParams := EncoderParams{
+					Width:       visionTrack.Width(),
+					Height:      visionTrack.Height(),
+					TimeBase:    visionTrack.TimeBase(),
+					AspectRatio: visionTrack.AspectRatio(),
+					PixelFormat: visionTrack.PixelFormat(),
+				}
+
+				encoder, err := NewEncoder(encoderParams)
+
+				if err != nil {
+					log.Fatal(fmt.Errorf("main: creating track failed: %w", err))
+					return
+				}
+				defer encoder.Close()
+
 				go visionTrack.Start()
 				defer visionTrack.Stop()
+
 				for visionTrack != nil {
+					var rtpPacket []byte
 					for frame := range visionTrack.Frame {
 						// Do something with decoded frame
 						fmt.Println(frame.Roll)
-
 						// so right now frame is a raw decoded AVFrame
 						// https://github.com/FFmpeg/FFmpeg/blob/n5.0/libavutil/frame.h#L317
-						// avframe := frame.Frame
+						avframe := frame.Frame
 
 						// we need to:
 						// 1. transcode to h264 with adaptive bitrate using astiav
+						outFrame, err := encoder.Encode(avframe)
+						if err != nil {
+							log.Println(fmt.Errorf("encode error: %w", err))
+
+							continue
+						}
 
 						// 2. create an RTP packet with h264 data inside using pion's rtp packetizer
-						var rtpPacket []byte
-						// 3. write the RTP packet to the videoTrack
+						fmt.Println(len(outFrame.Data()))
 
+						// 3. write the RTP packet to the videoTrack
 						if _, err = videoTrack.Write(rtpPacket); err != nil {
 							if errors.Is(err, io.ErrClosedPipe) {
 								// The peerConnection has been closed.

run.sh

@@ -1,4 +1,4 @@
-export CGO_LDFLAGS="-L$PWD/go-astiav/tmp/n4.4.1/lib/"
-export CGO_CXXFLAGS="-I$PWD/go-astiav/tmp/n4.4.1/include/"
+export CGO_LDFLAGS="-L$PWD/go-astiav/tmp/n4.4.1/lib"
+export CGO_CXXFLAGS="-I$PWD/go-astiav/tmp/n4.4.1/include"
 export PKG_CONFIG_PATH="$PWD/go-astiav/tmp/n4.4.1/lib/pkgconfig"
 go run .

vision_ipc_track.go

@@ -14,7 +14,7 @@ import (
 
 const V4L2_BUF_FLAG_KEYFRAME = uint32(8)
 
-type Stream struct {
+type VisionIpcTrackDecoderStream struct {
 	decCodec        *astiav.Codec
 	decCodecContext *astiav.CodecContext
 	inputStream     *astiav.Stream
@@ -22,7 +22,7 @@ type Stream struct {
 
 type VisionIpcTrack struct {
 	name       string
-	stream     *Stream
+	stream     *VisionIpcTrackDecoderStream
 	context    *zmq.Context
 	subscriber *zmq.Socket
 	lastIdx    int64
@@ -64,7 +64,7 @@ func NewVisionIpcTrack(name string) (track *VisionIpcTrack, err error) {
 	subscriber.Connect(GetServiceURI(name))
 
 	// Create stream
-	s := &Stream{inputStream: nil}
+	s := &VisionIpcTrackDecoderStream{inputStream: nil}
 
 	// Find decoder
 	if s.decCodec = astiav.FindDecoder(astiav.CodecIDHevc); s.decCodec == nil {
@@ -76,6 +76,12 @@ func NewVisionIpcTrack(name string) (track *VisionIpcTrack, err error) {
 		return nil, errors.New("main: codec context is nil")
 	}
 
+	s.decCodecContext.SetHeight(track.Height())
+	s.decCodecContext.SetPixelFormat(track.PixelFormat())
+	s.decCodecContext.SetSampleAspectRatio(track.AspectRatio())
+	s.decCodecContext.SetTimeBase(track.TimeBase())
+	s.decCodecContext.SetWidth(track.Width())
+
 	// Open codec context
 	if err := s.decCodecContext.Open(s.decCodec, nil); err != nil {
 		log.Fatal(fmt.Errorf("main: opening codec context failed: %w", err))
@@ -107,6 +113,30 @@ func NewVisionIpcTrack(name string) (track *VisionIpcTrack, err error) {
 	}, nil
 }
 
+func (v *VisionIpcTrack) TimeBase() (t astiav.Rational) {
+	return astiav.NewRational(v.FrameRate(), 1)
+}
+
+func (v *VisionIpcTrack) FrameRate() int {
+	return 20
+}
+
+func (v *VisionIpcTrack) Height() int {
+	return 1208
+}
+
+func (v *VisionIpcTrack) Width() int {
+	return 1928
+}
+
+func (v *VisionIpcTrack) AspectRatio() (t astiav.Rational) {
+	return astiav.NewRational(151, 241)
+}
+
+func (v *VisionIpcTrack) PixelFormat() (f astiav.PixelFormat) {
+	return astiav.PixelFormatYuv420P
+}
+
 func (v *VisionIpcTrack) Stop() {
 	if !Open {
 		return