private void AddVideoParamaterSet(VideoSample sample)
{
var configpart = VideoParameter.Split(',');
// Add SPS
sample.BeginUnit();
sample.AddUnitData(Convert.FromBase64String(configpart[0]));
sample.EndUnit();
// Add PPS
sample.BeginUnit();
sample.AddUnitData(Convert.FromBase64String(configpart[1]));
sample.EndUnit();
}
private IRtspSample OnVideoPacket(long sampleTime, RtpPacket packet, bool discontinuity)
{
if (discontinuity)
{
// clear fragmented NAL unit
_lastVideoSample = null;
}
var data = packet.PayloadData.ToArray();
if (data.Length < 1)
{
return(null);
}
// Interleaved mode is not supported.
var nalUnitFlags = data[0] & 0xe0;
var nalUnitType = data[0] & 0x1f;
if (nalUnitType <= 23)
{
// NAL unit (one packet, one NAL)
//Trace.WriteLine($"RtspHandler::OnVideoPacket(): NALType({nalUnitType}) Timestamp={packet.Timestamp} Length={data.Length}");
var sample = new VideoSample(sampleTime, discontinuity, (nalUnitType == 5));
if (sampleTime == 0)
{
AddVideoParamaterSet(sample);
}
sample.BeginUnit();
sample.AddUnitData(data);
sample.EndUnit();
sample.Commit();
return(sample);
}
if (nalUnitType == 24)
{
// STAP-A (Single-time aggregation packet: one packet, multiple NALs)
// TBD
Debug.WriteLine("RtspHandler::OnVideoPacket(): STAP-A");
return(null);
}
if (nalUnitType == 28)
{
// FU-A (Fragmentation Units: multiple packets, one NAL)
//var fuIndicator = data[0];
var fuHeader = data[1];
if ((fuHeader & 0x80) != 0) // check start bit
// start of a fragmented NAL unit
{
var fuNalUnitType = fuHeader & 0x1f;
//Trace.WriteLine($"RtspHandler::OnVideoPacket(): FU-A Start NALType({fuNalUnitType}) Timestamp={packet.Timestamp} Length={data.Length - 2}");
if (_lastVideoSample != null)
{
Debug.WriteLine("RtspHandler::OnVideoPacket(): Invalid fragmented NAL start.");
}
_lastVideoSample = new VideoSample(sampleTime, discontinuity, (fuNalUnitType == 5));
if (sampleTime == 0)
{
AddVideoParamaterSet(_lastVideoSample);
}
_lastVideoSample.BeginUnit();
_lastVideoSample.AddUnitData((byte)(nalUnitFlags | fuNalUnitType));
_lastVideoSample.AddUnitData(data.Skip(2));
return(null);
}
if (discontinuity)
{
Debug.WriteLine("RtspHandler::OnVideoPacket(): Ignore middle-started fragmented NAL.");
return(null);
}
if ((fuHeader & 0x40) != 0) // check end bit
// end of a fragmented NAL unit
//Trace.WriteLine($"RtspHandler::OnVideoPacket(): FU-A End Timestamp={packet.Timestamp} Length={data.Length - 2}");
{
if (_lastVideoSample != null)
{
_lastVideoSample.AddUnitData(data.Skip(2));
_lastVideoSample.EndUnit();
_lastVideoSample.Commit();
var sample = _lastVideoSample;
_lastVideoSample = null;
return(sample);
}
else
{
Debug.WriteLine("RtspHandler::OnVideoPacket(): Invalid fragmented NAL end.");
return(null);
}
}
// following FU payload
//Trace.WriteLine($"RtspHandler::OnVideoPacket(): FU-A Continue Timestamp={packet.Timestamp} Length={data.Length - 2}");
if (_lastVideoSample != null)
{
_lastVideoSample.AddUnitData(data.Skip(2));
}
else
{
Debug.WriteLine("RtspHandler::OnVideoPacket(): Invalid fragmented NAL.");
}
return(null);
}
Debug.WriteLine($"RtspHandler::OnVideoPacket(): Unknown NALType({nalUnitType})");
return(null);
}