public RtpUdpReceiver(RtpSession session)
{
this.session = session;
}
public RtpTcpSender(RtpSession session)
{
this.session = session;
}
public List <RtspFrame> ProcessData(byte[] buf, int length, RtpSession session)
{
List <RtspFrame> frames = new List <RtspFrame>();
int offset = 0;
int pos = 0;
while (true)
{
if (offset >= length)
{
logger.Debug("!!!!!!!!!!!!!!!!!!! " + offset + " >= " + length);
break;
//return;
}
if (tcpBufferOffset > 0)
{// если остались не обработанные данные
int len = length - offset;
int newSize = tcpBufferOffset + len;
byte[] newBuf = new byte[newSize];
Array.Copy(tcpBuffer, 0, newBuf, 0, tcpBufferOffset);
Array.Copy(buf, offset, newBuf, tcpBufferOffset, len);
tcpBufferOffset = 0;
// Debug.WriteLine("ProcessTcpBuffer newSize " + newSize);
buf = newBuf;
length = newSize;
}
if (streamState == RtspStreamState.WaitDollar ||
streamState == RtspStreamState.ReadHeader ||
streamState == RtspStreamState.ReadContent)
{
for (int i = offset; i < length; i++)
{
char ch = (char)buf[i];
if (ch == '$')
{
//Console.WriteLine("Find dollar at pos: " + i);
streamState = RtspStreamState.ReadId;
pos = i + 1; //header
rtspFrame = new RtspFrame();
break;
}
}
}
if (streamState == RtspStreamState.ReadId)
{// идентификатор 1 байт
int len = length - pos;
if (len > 0)
{
rtspFrame.Id = buf[pos];
//Console.WriteLine("ID: " + rtspFrame.Id + " pos: " + pos);
pos++;
streamState = RtspStreamState.ReadLen;
}
else
{ // буфер закончился выходим
break;
}
}
if (streamState == RtspStreamState.ReadLen)
{// длина пакета с данными 2 байта
int len = length - pos;
if (len > 1)
{
//int frameLength = BitConverter.ToInt16(buf, pos);
int frameLength = BigEndian.ReadInt16(buf, pos);
if (frameLength <= 0)
{
logger.Warn("frameLength " + frameLength);
//TODO:
//...
}
rtspFrame.Init(frameLength);
//Console.WriteLine("frameLength: " + frameLength + " pos: " + pos);
pos += 2;
streamState = RtspStreamState.ReadPkt;
}
else
{// сохраняем в буффер то что есть и выходим
// Debug.WriteLine(len + " < " + 2);
Array.Copy(buf, pos, tcpBuffer, tcpBufferOffset, len);
tcpBufferOffset += len;
//...
break;
}
}
if (streamState == RtspStreamState.ReadPkt)
{
if (rtspFrame != null && rtspFrame.Length > 0)
{
// сколькоданных в буфере
int bufToRead = length - pos;
int bytesAdded = rtspFrame.AddData(buf, pos, bufToRead);
pos += bytesAdded;
if (rtspFrame.BytesToRead == 0)
{// все данные прочитаны
// client.ProcessRtspFrame(rtspFrame);
//Console.WriteLine(rtspFrame.ToString());
var rtpData = rtspFrame.Data;
RtpPacket rtpPacket = RtpPacket.Create(rtpData, rtpData.Length, session);
// OnRtpPacketReceived(rtpPacket);
frames.Add(rtspFrame);
// переходим в режим ожидания доллара
streamState = RtspStreamState.WaitDollar;
// читаем следующий rtsp frame
rtspFrame = null;
}
if (pos < length)
{
//ProcessTcpBuffer(buf, pos, length);
offset = pos;
continue;
}
break;
// return;
}
}
{ // понять что это за данные пока не удалось копируем в буфер
int bufToRead = length - offset;
Array.Copy(buf, offset, tcpBuffer, tcpBufferOffset, bufToRead);
tcpBufferOffset += bufToRead;
logger.Debug("Array.Copy tcpBufferOffset " + tcpBufferOffset);
break;
}
}
return(frames);
}
//public static RtpPacket Create(byte[] data)
//{
// return Create(data, data.Length);
//}
public static RtpPacket Create(byte[] data, int len, RtpSession session)
{
if (len < RtpConst.MinRtpLength)
{
throw new InvalidOperationException("Invalid RTP packet. Packet size < " + RtpConst.MinRtpLength);
}
RtpPacket packet = new RtpPacket();
packet.packetBytes = data;
int dataLength = len;//data.Length;
int offset = 0;
byte firstByte = data[offset++];
packet.Version = (byte)(firstByte >> 6);
if (packet.Version != RtpConst.Version)
{
throw new InvalidOperationException("Invalid RTP packet. Unsupported version " + packet.Version);
}
/*
* If the padding bit is set, the packet contains one or more
* additional padding octets at the end which are not part of the
* payload. The last octet of the padding contains a count of how
* many padding octets should be ignored, including itself. Padding
* may be needed by some encryption algorithms with fixed block sizes
* or for carrying several RTP packets in a lower-layer protocol data
* unit.
*/
packet.Padding = ((firstByte & 0x20) == 0x20);
if (packet.Padding)
{// последний байт в пакете длинна области заполнения
byte padding = data.Last();
dataLength -= padding;
}
packet.Extension = (firstByte & 0x10) == 0x10;
packet.CSRCCount = (byte)(firstByte & 0x0F);
byte secondByte = data[offset++];
packet.Marker = (secondByte & 0x80) == 0x80;
packet.PayloadType = (secondByte & 0x7F);
packet.Sequence = BigEndian.ReadUInt16(data, offset);
offset += 2;
packet.Timestamp = BigEndian.ReadUInt32(data, offset);
offset += 4;
packet.SSRC = BigEndian.ReadUInt32(data, offset);
offset += 4;
if (packet.SSRC != session.SSRC)
{// Invalid session id
return(null);
}
offset += packet.CSRCCount * 4;
if (packet.Extension)
{ /*
* An extension mechanism is provided to allow individual
* implementations to experiment with new payload-format-independent
* functions that require additional information to be carried in the
* RTP data packet header. This mechanism is designed so that the
* header extension may be ignored by other interoperating
* implementations that have not been extended.
*/
packet.HeaderExtensionProfile = BigEndian.ReadUInt16(data, offset);
offset += 2;
var headerExtensionLength = BigEndian.ReadUInt16(data, offset);
offset += 2;
packet.HeaderExtension = new ArraySegment <byte>(data, offset, headerExtensionLength);
offset += headerExtensionLength;
}
else
{
packet.HeaderExtensionProfile = 0;
}
int payloadLength = (dataLength - offset);
packet.Payload = new ArraySegment <byte>(data, offset, payloadLength);
return(packet);
}
