// Validates RtcpFeedback. It may modify given data by adding missing
// fields with default values.
// It throws if invalid.
public void ValidateRtcpFeedback(RtcpFeedback fb)
{
// Type is mandatory.
if (fb.Type is null)
{
throw new Exception("missing fb.type");
}
// Parameter is optional. If unset set it to an empty string.
if (fb.Parameter is null)
{
fb.Parameter = string.Empty;
}
}
public RtpParameters GetSendingRemoteRtpParameters(MediaKind kind,
ExtendedRtpCapabilities extendedRtpCapabilities)
{
List <RtpCodecParameters> codecs = new();
foreach (var extendedCodec in extendedRtpCapabilities.Codecs)
{
if (extendedCodec.Kind != kind)
{
continue;
}
RtpCodecParameters codec = new()
{
MimeType = extendedCodec.MimeType,
PayloadType = extendedCodec.LocalPayloadType,
ClockRate = extendedCodec.ClockRate,
Channels = extendedCodec.Channels,
Parameters = extendedCodec.RemoteParameters,
RtcpFeedback = extendedCodec.RtcpFeedback
};
codecs.Add(codec);
if (extendedCodec.LocalRtxPayloadType.HasValue)
{
RtpCodecParameters rtxCodec = new()
{
MimeType = $"{extendedCodec.Kind.DisplayName()}/rtx",
PayloadType = (int)extendedCodec.LocalRtxPayloadType,
ClockRate = extendedCodec.ClockRate,
Parameters = new Dictionary <string, object>
{
{ "apt", extendedCodec.LocalPayloadType }
},
RtcpFeedback = new RtcpFeedback[] { }
};
codecs.Add(rtxCodec);
}
}
List <RtpHeaderExtensionParameters> headerExtensions = new();
foreach (var extendedExtendion in extendedRtpCapabilities.HeaderExtensions)
{
// Ignore RTP extensions of a different kind and those not valid for sending.
if ((extendedExtendion.Kind != kind) ||
(extendedExtendion.Direction != Direction.SendRecv &&
extendedExtendion.Direction != Direction.SendOnly))
{
continue;
}
RtpHeaderExtensionParameters ext = new()
{
Uri = extendedExtendion.Uri,
Id = extendedExtendion.SendId,
Encrypt = (bool)extendedExtendion.PreferredEncrypt,
};
headerExtensions.Add(ext);
}
// Reduce codecs' RTCP feedback. Use Transport-CC if available, REMB otherwise.
if (headerExtensions.Any(ext =>
ext.Uri == "http://www.ietf.org/id/draft-holmer-rmcat-transport-wide-cc-extensions-01"))
{
foreach (var codec in codecs)
{
codec.RtcpFeedback = codec.RtcpFeedback
.Where(fb => fb.Type != "goog-remb").ToArray();
}
}
else if (headerExtensions.Any(ext =>
ext.Uri == "http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time"))
{
foreach (var codec in codecs)
{
codec.RtcpFeedback = codec.RtcpFeedback
.Where(fb => fb.Type != "transport-cc").ToArray();
}
}
else
{
foreach (var codec in codecs)
{
codec.RtcpFeedback = codec.RtcpFeedback
.Where(fb => fb.Type != "transport-cc" && fb.Type != "goog-remb").ToArray();
}
}
return(new RtpParameters
{
Codecs = codecs.ToArray(),
HeaderExtensions = headerExtensions.ToArray(),
Encodings = new RtpEncodingParameters[] { },
Rtcp = new()
});
}
public RtpParameters GetSendingRtpParameters(MediaKind kind, ExtendedRtpCapabilities extendedRtpCapabilities)
{
List <RtpCodecParameters> codecs = new();
foreach (var extendedCodec in extendedRtpCapabilities.Codecs)
{
if (extendedCodec.Kind != kind)
{
continue;
}
RtpCodecParameters codec = new()
{
MimeType = extendedCodec.MimeType,
PayloadType = extendedCodec.LocalPayloadType,
ClockRate = extendedCodec.ClockRate,
Channels = extendedCodec.Channels,
Parameters = extendedCodec.LocalParameters,
RtcpFeedback = extendedCodec.RtcpFeedback
};
codecs.Add(codec);
if (extendedCodec.LocalRtxPayloadType.HasValue)
{
RtpCodecParameters rtxCodec = new()
{
MimeType = $"{extendedCodec.Kind.DisplayName()}/rtx",
PayloadType = (int)extendedCodec.LocalRtxPayloadType,
ClockRate = extendedCodec.ClockRate,
Parameters = new Dictionary <string, object>
{
{ "apt", extendedCodec.LocalPayloadType }
},
RtcpFeedback = new RtcpFeedback[] { }
};
codecs.Add(rtxCodec);
}
}
List <RtpHeaderExtensionParameters> headerExtensions = new();
foreach (var extendedExtendion in extendedRtpCapabilities.HeaderExtensions)
{
// Ignore RTP extensions of a different kind and those not valid for sending.
if ((extendedExtendion.Kind != kind) ||
(extendedExtendion.Direction != Direction.SendRecv &&
extendedExtendion.Direction != Direction.SendOnly))
{
continue;
}
RtpHeaderExtensionParameters ext = new()
{
Uri = extendedExtendion.Uri,
Id = extendedExtendion.SendId,
Encrypt = (bool)extendedExtendion.PreferredEncrypt,
Parameters = new()
};
headerExtensions.Add(ext);
}
return(new RtpParameters
{
Codecs = codecs.ToArray(),
HeaderExtensions = headerExtensions.ToArray(),
Encodings = new RtpEncodingParameters[] { },
Rtcp = new()
});
}
public RtpCapabilities GetRecvRtpCapabilities(ExtendedRtpCapabilities extendedRtpCapabilities)
{
List <RtpCodecCapability> codecs = new();
foreach (var extendedCodec in extendedRtpCapabilities.Codecs)
{
RtpCodecCapability codec = new()
{
MimeType = extendedCodec.MimeType,
Kind = extendedCodec.Kind,
PreferredPayloadType = extendedCodec.RemotePayloadType,
ClockRate = extendedCodec.ClockRate,
Channels = extendedCodec.Channels,
Parameters = extendedCodec.LocalParameters,
RtcpFeedback = extendedCodec.RtcpFeedback
};
codecs.Add(codec);
if (extendedCodec.RemoteRtxPayloadType is null)
{
continue;
}
RtpCodecCapability rtxCodec = new()
{
MimeType = $"{extendedCodec.Kind.DisplayName()}/rtx",
Kind = extendedCodec.Kind,
PreferredPayloadType = (int)extendedCodec.RemoteRtxPayloadType,
ClockRate = extendedCodec.ClockRate,
//Parameters = new RtxParameters
//{
// Apt = extendedCodec.RemotePayloadType
//},
Parameters = new Dictionary <string, object /*string*/>()
{
{ "apt", extendedCodec.RemotePayloadType /*.ToString()*/ }
},
RtcpFeedback = new RtcpFeedback[] { }
};
codecs.Add(rtxCodec);
}
List <RtpHeaderExtension> headerExtensions = new();
foreach (var extendedExtensions in extendedRtpCapabilities.HeaderExtensions)
{
if (extendedExtensions.Direction != Direction.SendRecv &&
extendedExtensions.Direction != Direction.RecvOnly)
{
continue;
}
RtpHeaderExtension ext = new()
{
Kind = extendedExtensions.Kind,
Uri = extendedExtensions.Uri,
PreferredId = extendedExtensions.RecvId,
PreferredEncrypt = extendedExtensions.PreferredEncrypt,
Direction = extendedExtensions.Direction
};
headerExtensions.Add(ext);
}
return(new RtpCapabilities
{
Codecs = codecs.ToArray(),
HeaderExtensions = headerExtensions.ToArray()
});
}