IVF records can now be longer than 30s

- Added timeout to save-to-disk example
- Writing number of IVF frames when closing the file
- Fixed typos

Relates to #471

examples/save-to-disk/README.md

@@ -21,7 +21,8 @@ Run `echo $BROWSER_SDP | save-to-disk`
 ### Input save-to-disk's SessionDescription into your browser
 Copy the text that `save-to-disk` just emitted and copy into second text area
 
-### Hit 'Start Session' in jsfiddle, enjoy your video!
+### Hit 'Start Session' in jsfiddle, wait, close jsfiddle, enjoy your video!
 In the folder you ran `save-to-disk` you should now have a file `output-1.ivf` play with your video player of choice!
+> Note: In order to correctly create the files, the remote client (JSFiddle) should be closed. The Go example will automatically close itself.
 
 Congrats, you have used pion-WebRTC! Now start building something cool

examples/save-to-disk/main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"os"
 	"time"
 
 	"github.com/pions/rtcp"
@@ -21,12 +22,11 @@ func saveToDisk(i media.Writer, track *webrtc.Track) {
 	}()
 
 	for {
-		packet, err := track.ReadRTP()
+		rtpPacket, err := track.ReadRTP()
 		if err != nil {
 			panic(err)
 		}
-
-		if err := i.AddPacket(packet); err != nil {
+		if err := i.AddPacket(rtpPacket); err != nil {
 			panic(err)
 		}
 	}
@@ -61,6 +61,15 @@ func main() {
 		panic(err)
 	}
 
+	opusFile, err := opuswriter.New("output.opus", 48000, 2)
+	if err != nil {
+		panic(err)
+	}
+	ivfFile, err := ivfwriter.New("output.ivf")
+	if err != nil {
+		panic(err)
+	}
+
 	// Set a handler for when a new remote track starts, this handler saves buffers to disk as
 	// an ivf file, since we could have multiple video tracks we provide a counter.
 	// In your application this is where you would handle/process video
@@ -78,26 +87,28 @@ func main() {
 
 		codec := track.Codec()
 		if codec.Name == webrtc.Opus {
-			fmt.Println("Got Opus track, saving to disk as output.opus")
-			i, err := opuswriter.New("output.opus", codec.ClockRate, codec.Channels)
-			if err != nil {
-				panic(err)
-			}
-			saveToDisk(i, track)
+			fmt.Println("Got Opus track, saving to disk as output.opus (48 kHz, 2 channels)")
+			saveToDisk(opusFile, track)
 		} else if codec.Name == webrtc.VP8 {
 			fmt.Println("Got VP8 track, saving to disk as output.ivf")
-			i, err := ivfwriter.New("output.ivf")
-			if err != nil {
-				panic(err)
-			}
-			saveToDisk(i, track)
+			saveToDisk(ivfFile, track)
 		}
 	})
 
 	// Set the handler for ICE connection state
 	// This will notify you when the peer has connected/disconnected
 	peerConnection.OnICEConnectionStateChange(func(connectionState webrtc.ICEConnectionState) {
 		fmt.Printf("Connection State has changed %s \n", connectionState.String())
+
+		if connectionState == webrtc.ICEConnectionStateConnected {
+			fmt.Println("Ctrl+C the remote client to stop the demo")
+		} else if connectionState == webrtc.ICEConnectionStateFailed ||
+			connectionState == webrtc.ICEConnectionStateDisconnected {
+			opusFile.Close()
+			ivfFile.Close()
+			fmt.Println("Done writing media files")
+			os.Exit(0)
+		}
 	})
 
 	// Wait for the offer to be pasted

pkg/media/ivfwriter/ivfwriter.go

@@ -57,7 +57,7 @@ func (i *IVFWriter) writeHeader() error {
 	binary.LittleEndian.PutUint16(header[14:], 480) // Header Size
 	binary.LittleEndian.PutUint32(header[16:], 30)  // Framerate numerator
 	binary.LittleEndian.PutUint32(header[20:], 1)   // Framerate Denominator
-	binary.LittleEndian.PutUint32(header[24:], 900) // Frame count
+	binary.LittleEndian.PutUint32(header[24:], 900) // Frame count, will be updated on first Close() call
 	binary.LittleEndian.PutUint32(header[28:], 0)   // Unused
 
 	_, err := i.stream.Write(header)
@@ -108,9 +108,19 @@ func (i *IVFWriter) Close() error {
 	}()
 
 	if i.fd == nil {
-		// Returns no error has it may be convenient to call
+		// Returns no error as it may be convenient to call
 		// Close() multiple times
 		return nil
 	}
+	// Update the framecount
+	if _, err := i.fd.Seek(24, 0); err != nil {
+		return err
+	}
+	buff := make([]byte, 4)
+	binary.LittleEndian.PutUint32(buff, uint32(i.count))
+	if _, err := i.fd.Write(buff); err != nil {
+		return err
+	}
+
 	return i.fd.Close()
 }