Merged in rtp-encoder-buffer-fix (pull request #137)

stream/rtp/encoder.go: more sensible use of encoder buffer

Approved-by: kortschak <dan@kortschak.io>

stream/rtp/encoder.go

@@ -40,7 +40,7 @@ const (
 	timestampFreq  = 90000 // Hz
 	mtsSize        = 188
 	bufferSize     = 1000
-	sendLen        = 7 * 188
+	sendSize       = 7 * 188
 )
 
 // Encoder implements io writer and provides functionality to wrap data into
@@ -72,13 +72,29 @@ func NewEncoder(dst io.Writer, fps int) *Encoder {
 // so that multiple layers of packetization can occur.
 func (e *Encoder) Write(data []byte) (int, error) {
 	e.buffer = append(e.buffer, data...)
-	for len(e.buffer) >= sendLen {
-		e.Encode(e.buffer[:sendLen])
-		e.buffer = e.buffer[sendLen:]
+	if len(e.buffer) < sendSize {
+		return len(data), nil
 	}
+	buf := e.buffer
+	for len(buf) != 0 {
+		l := min(sendSize, len(buf))
+		err := e.Encode(buf[:l])
+		if err != nil {
+			return len(data), err
+		}
+		buf = buf[l:]
+	}
+	e.buffer = e.buffer[:0]
 	return len(data), nil
 }
 
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
 // Encode takes a nalu unit and encodes it into an rtp packet and
 // writes to the io.Writer given in NewEncoder
 func (e *Encoder) Encode(payload []byte) error {

stream/rtp/rtp.go

@@ -35,7 +35,7 @@ package rtp
 const (
 	rtpVer         = 2
 	headSize       = 3 * 4                     // Header size of an rtp packet.
-	defPayloadSize = sendLen                   // Default payload size for the rtp packet.
+	defPayloadSize = sendSize                  // Default payload size for the rtp packet.
 	defPktSize     = headSize + defPayloadSize // Default packet size is header size + payload size.
 )