Added RTMP_PACKET_SIZE_AUTO.

rtmp/packet.go

@@ -60,6 +60,7 @@ const (
 	RTMP_PACKET_SIZE_MEDIUM  = 1
 	RTMP_PACKET_SIZE_SMALL   = 2
 	RTMP_PACKET_SIZE_MINIMUM = 3
+	RTMP_PACKET_SIZE_AUTO    = 4
 )
 
 const (
@@ -260,9 +261,25 @@ func readPacket(s *Session, pkt *packet) error {
 // resizePacket adjusts the packet's storage to accommodate a body of the given size.
 func resizePacket(pkt *packet, size uint32, ht uint8) {
 	buf := make([]byte, RTMP_MAX_HEADER_SIZE+size)
-	pkt.headerType = ht
 	pkt.header = buf
 	pkt.body = buf[RTMP_MAX_HEADER_SIZE:]
+	if ht != RTMP_PACKET_SIZE_AUTO {
+		pkt.headerType = ht
+		return
+	}
+	switch pkt.packetType {
+	case RTMP_PACKET_TYPE_VIDEO, RTMP_PACKET_TYPE_AUDIO:
+		if pkt.timestamp == 0 {
+			pkt.headerType = RTMP_PACKET_SIZE_LARGE
+		} else {
+			pkt.headerType = RTMP_PACKET_SIZE_MEDIUM
+		}
+	case RTMP_PACKET_TYPE_INFO:
+		pkt.headerType = RTMP_PACKET_SIZE_LARGE
+		pkt.bodySize += 16
+	default:
+		pkt.headerType = RTMP_PACKET_SIZE_MEDIUM
+	}
 }
 
 // sendPacket sends a packet.

rtmp/rtmp_headers.go

@@ -91,7 +91,7 @@ const (
 	RTMP_BUFFER_CACHE_SIZE = (16 * 1024)
 	RTMP_SIG_SIZE          = 1536
 	RTMP_LARGE_HEADER_SIZE = 12
-	RTMP_MAX_HEADER_SIZE   = 18
+	RTMP_MAX_HEADER_SIZE   = RTMP_LARGE_HEADER_SIZE
 )
 
 type link struct {