/// <summary>
/// Audio frames are generally contained within a single RTP packet. This method is a shortcut
/// to construct a frame from a single RTP packet.
/// </summary>
public static RTPFrame MakeSinglePacketFrame(RTPPacket rtpPacket)
{
RTPFrame frame = new RTPFrame();
frame.AddRTPPacket(rtpPacket);
frame.Timestamp = rtpPacket.Header.Timestamp;
return(frame);
}
private void ProcessRTPPackets()
{
try
{
Thread.CurrentThread.Name = "rtspclient-rtp";
_lastRTPReceivedAt = DateTime.Now;
_lastBWCalcAt = DateTime.Now;
while (!_isClosed)
{
while (_rtspSession.HasRTPPacket())
{
RTPPacket rtpPacket = _rtspSession.GetNextRTPPacket();
if (rtpPacket != null)
{
_lastRTPReceivedAt = DateTime.Now;
_bytesSinceLastBWCalc += RTPHeader.MIN_HEADER_LEN + rtpPacket.Payload.Length;
if (_rtpTrackingAction != null)
{
double bwCalcSeconds = DateTime.Now.Subtract(_lastBWCalcAt).TotalSeconds;
if (bwCalcSeconds > BANDWIDTH_CALCULATION_SECONDS)
{
_lastBWCalc = _bytesSinceLastBWCalc * 8 / bwCalcSeconds;
_lastFrameRate = _framesSinceLastCalc / bwCalcSeconds;
_bytesSinceLastBWCalc = 0;
_framesSinceLastCalc = 0;
_lastBWCalcAt = DateTime.Now;
}
var abbrevURL = (_url.Length <= 50) ? _url : _url.Substring(0, 50);
string rtpTrackingText = String.Format(
"Url: {0}\r\nRcvd At: {1}\r\nSeq Num: {2}\r\nTS: {3}\r\nPayoad: {4}\r\nFrame Size: {5}\r\nBW: {6}\r\nFrame Rate: {7}",
abbrevURL, DateTime.Now.ToString("HH:mm:ss:fff"), rtpPacket.Header.SequenceNumber,
rtpPacket.Header.Timestamp,
((SDPMediaFormatsEnum)rtpPacket.Header.PayloadType).ToString(),
_lastFrameSize + " bytes", _lastBWCalc.ToString("0.#") + "bps",
_lastFrameRate.ToString("0.##") + "fps");
_rtpTrackingAction(rtpTrackingText);
}
if (rtpPacket.Header.Timestamp < _lastCompleteFrameTimestamp)
{
Debug.WriteLine(
"Ignoring RTP packet with timestamp " + rtpPacket.Header.Timestamp +
" as it's earlier than the last complete frame.");
}
else
{
while (_frames.Count > MAX_FRAMES_QUEUE_LENGTH)
{
var oldestFrame = _frames.OrderBy(x => x.Timestamp).First();
_frames.Remove(oldestFrame);
Debug.WriteLine(
"Receive queue full, dropping oldest frame with timestamp " +
oldestFrame.Timestamp + ".");
}
var frame = _frames.Where(x => x.Timestamp == rtpPacket.Header.Timestamp)
.SingleOrDefault();
if (frame == null)
{
frame = new RTPFrame()
{
Timestamp = rtpPacket.Header.Timestamp,
HasMarker = rtpPacket.Header.MarkerBit == 1
};
frame.AddRTPPacket(rtpPacket);
_frames.Add(frame);
}
else
{
frame.HasMarker = (rtpPacket.Header.MarkerBit == 1);
frame.AddRTPPacket(rtpPacket);
}
if (frame.IsComplete)
{
// The frame is ready for handing over to the UI.
byte[] imageBytes = frame.GetFramePayload();
_lastFrameSize = imageBytes.Length;
_framesSinceLastCalc++;
_lastCompleteFrameTimestamp = rtpPacket.Header.Timestamp;
//System.Diagnostics.Debug.WriteLine("Frame ready " + frame.Timestamp + ", sequence numbers " + frame.StartSequenceNumber + " to " + frame.EndSequenceNumber + ", payload length " + imageBytes.Length + ".");
//logger.Debug("Frame ready " + frame.Timestamp + ", sequence numbers " + frame.StartSequenceNumber + " to " + frame.EndSequenceNumber + ", payload length " + imageBytes.Length + ".");
_frames.Remove(frame);
// Also remove any earlier frames as we don't care about anything that's earlier than the current complete frame.
foreach (var oldFrame in _frames
.Where(x => x.Timestamp <= rtpPacket.Header.Timestamp).ToList())
{
Debug.WriteLine(
"Discarding old frame for timestamp " + oldFrame.Timestamp + ".");
logger.Warn("Discarding old frame for timestamp " + oldFrame.Timestamp + ".");
_frames.Remove(oldFrame);
}
if (OnFrameReady != null)
{
try
{
//if (frame.FramePackets.Count == 1)
//{
// // REMOVE.
// logger.Warn("Discarding frame as there should have been more than 1 RTP packets.");
//}
//else
//{
//System.Diagnostics.Debug.WriteLine("RTP frame ready for timestamp " + frame.Timestamp + ".");
OnFrameReady(this, frame);
//}
}
catch (Exception frameReadyExcp)
{
logger.Error("Exception RTSPClient.ProcessRTPPackets OnFrameReady. " +
frameReadyExcp);
}
}
}
}
}
}
if (DateTime.Now.Subtract(_lastRTPReceivedAt).TotalSeconds > RTP_TIMEOUT_SECONDS)
{
logger.Warn("No RTP packets were received on RTSP session " + _rtspSession.SessionID + " for " +
RTP_TIMEOUT_SECONDS + ". The session will now be closed.");
Close();
}
else
{
Thread.Sleep(1);
}
}
}
catch (Exception excp)
{
logger.Error("Exception RTSPClient.ProcessRTPPackets. " + excp);
}
}
