Remove audio encoding

Also begin refactor of removing 'frames'.

This is now semi functional again. Still only the first client will
work.

videostreamer.go

@@ -15,6 +15,8 @@ import (
 // #include "videostreamer.h"
 // #include <stdlib.h>
 // #cgo LDFLAGS: -lavformat -lavdevice -lavcodec -lavutil
+// #cgo CFLAGS: -std=c11
+// #cgo pkg-config: libavcodec
 import "C"
 
 // Args holds command line arguments.
@@ -25,37 +27,20 @@ type Args struct {
 	InputURL    string
 	Verbose     bool
 	// Serve with FCGI protocol (true) or HTTP (false).
-	FCGI    bool
-	Encoder EncoderType
+	FCGI bool
 }
 
-// EncoderType defines the type of streaming we're doing.
-type EncoderType int
-
-const (
-	// AudioEncoder means to encode audio.
-	AudioEncoder EncoderType = iota
-	// VideoEncoder means to encode video.
-	VideoEncoder
-)
-
 // HTTPHandler allows us to pass information to our request handlers.
 type HTTPHandler struct {
 	Verbose          bool
 	ClientChangeChan chan<- int
 	ClientChan       chan<- Client
-	Encoder          EncoderType
 }
 
 // A Client is servicing one HTTP client. It receives frames from the reader.
 type Client struct {
-	Frames chan Frame
-	Done   chan struct{}
-}
-
-// Frame is an audio/video frame (compressed and encoded).
-type Frame struct {
-	Buffer []byte
+	Data chan []byte
+	Done chan struct{}
 }
 
 func main() {
@@ -64,12 +49,7 @@ func main() {
 		log.Fatalf("Invalid argument: %s", err)
 	}
 
-	if args.Encoder == AudioEncoder {
-		C.as_setup()
-	}
-	if args.Encoder == VideoEncoder {
-		C.vs_setup()
-	}
+	C.vs_setup()
 
 	// Encoder writes to out pipe. Reader reads from in pipe.
 	in, out, err := os.Pipe()
@@ -94,11 +74,10 @@ func main() {
 	// receive. Otherwise if it reads without knowing frame boundaries, it is
 	// difficult for it to know when it is valid to start sending data to a
 	// client that enters mid-encoding.
-	frameChan := make(chan int)
-	//frameChan := make(chan int, 128)
+	frameChan := make(chan int, 128)
 
 	go encoderSupervisor(out, args.InputFormat, args.InputURL, args.Verbose,
-		clientChangeChan, frameChan, args.Encoder)
+		clientChangeChan, frameChan)
 	go reader(args.Verbose, in, clientChan, frameChan)
 
 	// Start serving either with HTTP or FastCGI.
@@ -109,7 +88,6 @@ func main() {
 		Verbose:          args.Verbose,
 		ClientChangeChan: clientChangeChan,
 		ClientChan:       clientChan,
-		Encoder:          args.Encoder,
 	}
 
 	if args.FCGI {
@@ -143,11 +121,10 @@ func main() {
 func getArgs() (Args, error) {
 	listenHost := flag.String("host", "0.0.0.0", "Host to listen on.")
 	listenPort := flag.Int("port", 8080, "Port to listen on.")
-	format := flag.String("format", "pulse", "Input format. Examples: pulse for PulseAudio, mp3 for MP3, or rtsp for RTSP.")
-	input := flag.String("input", "", "Input URL valid for the given format. For MP3 you can give this as a path to a file. For PulseAudio you can give a value such as alsa_output.pci-0000_00_1f.3.analog-stereo.monitor to take input from a monitor. Use 'pactl list sources' to show the available PulseAudio sources. For RTSP you can provide a rtsp:// URL.")
+	format := flag.String("format", "pulse", "Input format. Example: rtsp for RTSP.")
+	input := flag.String("input", "", "Input URL valid for the given format. For RTSP you can provide a rtsp:// URL.")
 	verbose := flag.Bool("verbose", false, "Enable verbose logging output.")
 	fcgi := flag.Bool("fcgi", true, "Serve using FastCGI (true) or as a regular HTTP server.")
-	encoder := flag.String("encoder", "audio", "Stream audio or video. Each uses different encoding methods.")
 
 	flag.Parse()
 
@@ -166,16 +143,6 @@ func getArgs() (Args, error) {
 		return Args{}, fmt.Errorf("you must provide an input URL")
 	}
 
-	encoderType := AudioEncoder
-	if *encoder == "audio" {
-		encoderType = AudioEncoder
-	} else if *encoder == "video" {
-		encoderType = VideoEncoder
-	} else {
-		flag.PrintDefaults()
-		return Args{}, fmt.Errorf("you must specify encoder as audio or video")
-	}
-
 	return Args{
 		ListenHost:  *listenHost,
 		ListenPort:  *listenPort,
@@ -183,7 +150,6 @@ func getArgs() (Args, error) {
 		InputURL:    *input,
 		Verbose:     *verbose,
 		FCGI:        *fcgi,
-		Encoder:     encoderType,
 	}, nil
 }
 
@@ -193,8 +159,7 @@ func getArgs() (Args, error) {
 // time no matter how many clients there are. If there are zero clients, there
 // should not be any encoding going on.
 func encoderSupervisor(outPipe *os.File, inputFormat, inputURL string,
-	verbose bool, clientChangeChan <-chan int, frameChan chan<- int,
-	encoder EncoderType) {
+	verbose bool, clientChangeChan <-chan int, frameChan chan<- int) {
 	// A count of how many clients are actively subscribed listening for
 	// audio/video. We start the encoder when this goes above zero, and stop it
 	// if it goes to zero.
@@ -228,14 +193,8 @@ func encoderSupervisor(outPipe *os.File, inputFormat, inputURL string,
 
 					encoderStopChan = make(chan struct{})
 
-					if encoder == AudioEncoder {
-						go audioEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
-							encoderDoneChan, frameChan)
-					}
-					if encoder == VideoEncoder {
-						go videoEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
-							encoderDoneChan, frameChan)
-					}
+					go videoEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
+						encoderDoneChan, frameChan)
 				}
 
 				continue
@@ -275,95 +234,8 @@ func encoderSupervisor(outPipe *os.File, inputFormat, inputURL string,
 
 			encoderStopChan = make(chan struct{})
 
-			if encoder == AudioEncoder {
-				go audioEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
-					encoderDoneChan, frameChan)
-			}
-			if encoder == VideoEncoder {
-				go videoEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
-					encoderDoneChan, frameChan)
-			}
-		}
-	}
-}
-
-// audioEncoder opens an audio input and begins decoding. It re-encodes the
-// audio out and writes it to a pipe. It informs the reader goroutine how large
-// each audio frame it writes is.
-func audioEncoder(outPipe *os.File, inputFormat, inputURL string,
-	stopChan <-chan struct{}, doneChan chan<- struct{}, frameChan chan<- int) {
-	inputFormatC := C.CString(inputFormat)
-	inputURLC := C.CString(inputURL)
-	verbose := C.bool(false)
-
-	input := C.as_open_input(inputFormatC, inputURLC, verbose)
-	if input == nil {
-		log.Printf("Unable to open input")
-		C.free(unsafe.Pointer(inputFormatC))
-		C.free(unsafe.Pointer(inputURLC))
-		doneChan <- struct{}{}
-		return
-	}
-	C.free(unsafe.Pointer(inputFormatC))
-	C.free(unsafe.Pointer(inputURLC))
-
-	outputFormat := C.CString("mp3")
-	outputURL := C.CString(fmt.Sprintf("pipe:%d", outPipe.Fd()))
-	outputEncoder := C.CString("libmp3lame")
-
-	output := C.as_open_output(input, outputFormat, outputURL, outputEncoder)
-	if output == nil {
-		log.Printf("Unable to open output")
-		C.as_destroy_input(input)
-		C.free(unsafe.Pointer(outputFormat))
-		C.free(unsafe.Pointer(outputURL))
-		C.free(unsafe.Pointer(outputEncoder))
-		doneChan <- struct{}{}
-		return
-	}
-	C.free(unsafe.Pointer(outputFormat))
-	C.free(unsafe.Pointer(outputURL))
-	C.free(unsafe.Pointer(outputEncoder))
-
-	audiostreamer := C.as_init_audiostreamer(input, output)
-	if audiostreamer == nil {
-		log.Printf("Unable to initialize audiostreamer")
-		C.as_destroy_output(output)
-		C.as_destroy_input(input)
-		doneChan <- struct{}{}
-		return
-	}
-	defer C.as_destroy_audiostreamer(audiostreamer)
-
-	for {
-		select {
-		// If stop channel is closed then we stop what we're doing.
-		case <-stopChan:
-			log.Printf("Stopping encoder")
-			doneChan <- struct{}{}
-			return
-		default:
-		}
-
-		frameSize := C.int(0)
-		res := C.as_read_write(audiostreamer, &frameSize)
-		if res == -1 {
-			log.Printf("Failure decoding/encoding")
-			doneChan <- struct{}{}
-			return
-		}
-
-		// EOF. Typical usage will never have EOF. However if we run with a file as
-		// input then this may happen.
-		if res == 0 {
-			doneChan <- struct{}{}
-			return
-		}
-
-		// We did some work.
-
-		if frameSize > 0 {
-			frameChan <- int(frameSize)
+			go videoEncoder(outPipe, inputFormat, inputURL, encoderStopChan,
+				encoderDoneChan, frameChan)
 		}
 	}
 }
@@ -471,20 +343,20 @@ func reader(verbose bool, inPipe *os.File, clientChan <-chan Client,
 }
 
 // Read a frame.
-func readFrame(reader *bufio.Reader, size int) (Frame, error) {
+func readFrame(reader *bufio.Reader, size int) ([]byte, error) {
 	buf := []byte{}
 	bytesNeeded := size
 
 	for {
 		if bytesNeeded == 0 {
-			return Frame{Buffer: buf}, nil
+			return buf, nil
 		}
 
 		readBuf := make([]byte, bytesNeeded)
 
 		n, err := reader.Read(readBuf)
 		if err != nil {
-			return Frame{}, fmt.Errorf("read: %s", err)
+			return nil, fmt.Errorf("read: %s", err)
 		}
 
 		log.Printf("read %d bytes", n)
@@ -498,7 +370,7 @@ func readFrame(reader *bufio.Reader, size int) (Frame, error) {
 // Try to send the given frame to each client.
 //
 // If sending would block, cut the client off.
-func sendFrameToClients(clients []Client, frame Frame) []Client {
+func sendFrameToClients(clients []Client, frame []byte) []Client {
 	clients2 := []Client{}
 
 	for _, client := range clients {
@@ -518,15 +390,15 @@ func sendFrameToClients(clients []Client, frame Frame) []Client {
 // This lets us know if we should consider the client dead.
 //
 // Close the client's frame channel if we fail to send so it knows to go away.
-func sendFrameToClient(client Client, frame Frame) error {
+func sendFrameToClient(client Client, frame []byte) error {
 	select {
-	case client.Frames <- frame:
+	case client.Data <- frame:
 		return nil
 	case <-client.Done:
-		close(client.Frames)
+		close(client.Data)
 		return fmt.Errorf("client went away")
 	default:
-		close(client.Frames)
+		close(client.Data)
 		return fmt.Errorf("client is too slow")
 	}
 }
@@ -549,7 +421,7 @@ func (h HTTPHandler) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
 func (h HTTPHandler) streamRequest(rw http.ResponseWriter, r *http.Request) {
 	c := Client{
 		// We receive audio/video data on this channel from the reader.
-		Frames: make(chan Frame, 1024),
+		Data: make(chan []byte, 1024),
 
 		// We close this channel to indicate to reader we're done. This is necessary
 		// if we terminate, otherwise the reader can't know to stop sending us
@@ -563,19 +435,14 @@ func (h HTTPHandler) streamRequest(rw http.ResponseWriter, r *http.Request) {
 	// Tell the encoder we're here.
 	h.ClientChangeChan <- 1
 
-	if h.Encoder == AudioEncoder {
-		rw.Header().Set("Content-Type", "audio/mpeg")
-	}
-	if h.Encoder == VideoEncoder {
-		rw.Header().Set("Content-Type", "video/mp4")
-	}
+	rw.Header().Set("Content-Type", "video/mp4")
 
 	rw.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
 
 	// We send chunked by default
 
 	for {
-		frame, ok := <-c.Frames
+		frame, ok := <-c.Data
 
 		// Reader may have cut us off.
 		if !ok {
@@ -583,13 +450,13 @@ func (h HTTPHandler) streamRequest(rw http.ResponseWriter, r *http.Request) {
 			break
 		}
 
-		n, err := rw.Write(frame.Buffer)
+		n, err := rw.Write(frame)
 		if err != nil {
 			log.Printf("write: %s", err)
 			break
 		}
 
-		if n != len(frame.Buffer) {
+		if n != len(frame) {
 			log.Printf("short write")
 			break
 		}
@@ -610,7 +477,7 @@ func (h HTTPHandler) streamRequest(rw http.ResponseWriter, r *http.Request) {
 	close(c.Done)
 
 	// Drain frames channel.
-	for range c.Frames {
+	for range c.Data {
 	}
 
 	log.Printf("%s: Client cleaned up", r.RemoteAddr)