public RtpHeader(RtpHeader other, bool shouldDispose = true)
: base(shouldDispose)
{
First16Bits = new RFC3550.CommonHeaderBits(other.First16Bits, shouldDispose);
SegmentToLast10Bytes = new Common.MemorySegment(other.SegmentToLast10Bytes, shouldDispose);
}
/// <summary>
/// Creates a RtpPacket instance by copying data from the given buffer at the given offset.
/// </summary>
/// <param name="buffer">The buffer which contains the binary RtpPacket to decode</param>
/// <param name="offset">The offset to start copying</param>
public RtpPacket(byte[] buffer, int offset, int count)
{
if (buffer == null || buffer.Length == 0)
{
throw new ArgumentException("Must have data in a RtpPacket");
}
//Read the header
Header = new RtpHeader(buffer, offset);
ShouldDispose = m_OwnsHeader = true;
if (count > RtpHeader.Length && !Header.IsCompressed)
{
//Advance the pointer
offset += RtpHeader.Length;
count -= RtpHeader.Length;
m_OwnedOctets = new byte[count];
Array.Copy(buffer, offset, m_OwnedOctets, 0, count);
//Create a segment to the payload deleniated by the given offset and the constant Length of the RtpHeader.
Payload = new MemorySegment(m_OwnedOctets, 0, count);
}
else
{
m_OwnedOctets = Media.Common.MemorySegment.EmptyBytes; //IsReadOnly should be false
//Payload = new MemoryReference(m_OwnedOctets, 0, 0, m_OwnsHeader);
Payload = new MemorySegment(0);
}
}
/// <summary>
/// Creates a RtpPacket instance from an existing RtpHeader and payload.
/// Check the IsValid property to see if the RtpPacket is well formed.
/// </summary>
/// <param name="header">The existing RtpHeader</param>
/// <param name="payload">The data contained in the payload</param>
public RtpPacket(RtpHeader header, MemorySegment payload, bool ownsHeader = true)
{
if (header == null)
{
throw new ArgumentNullException("header");
}
Header = header;
ShouldDispose = m_OwnsHeader = ownsHeader;
Payload = payload;
}
/// <summary>
/// Creates an exact copy of the RtpHeader from the given RtpHeader
/// </summary>
/// <param name="other">The RtpHeader to copy</param>
/// <param name="reference">A value indicating if the RtpHeader given should be referenced or copied.</param>
public RtpHeader(RtpHeader other, bool reference)
{
if (reference)
{
First16Bits = other.First16Bits;
Last10Bytes = other.Last10Bytes;
PointerToLast10Bytes = other.PointerToLast10Bytes;
}
else
{
First16Bits = new Media.RFC3550.CommonHeaderBits(other.First16Bits);
Last10Bytes = new byte[10];
PointerToLast10Bytes = new Common.MemorySegment(Last10Bytes, 0, 10);
other.Last10Bytes.CopyTo(Last10Bytes, 0);
}
}
public RtpHeader(RtpHeader other, bool reference, bool shouldDispose = true)
: base(shouldDispose)
{
if (reference)
{
First16Bits = other.First16Bits;
Last10Bytes = other.Last10Bytes;
SegmentToLast10Bytes = other.SegmentToLast10Bytes;
}
else
{
First16Bits = new Media.RFC3550.CommonHeaderBits(other.First16Bits);
Last10Bytes = new byte[10];
SegmentToLast10Bytes = new Common.MemorySegment(Last10Bytes, 0, 10);
other.Last10Bytes.CopyTo(Last10Bytes, 0);
}
}
public override bool Equals(object obj)
{
if (System.Object.ReferenceEquals(this, obj))
{
return(true);
}
if (!(obj is RtpHeader))
{
return(false);
}
RtpHeader other = obj as RtpHeader;
return(other.First16Bits == First16Bits
&&
other.SynchronizationSourceIdentifier == SynchronizationSourceIdentifier);
}
/// <summary>
/// Creates a RtpPacket instance by projecting the given sequence to an array which is subsequently owned by the instance.
/// </summary>
/// <param name="header">The header to utilize. When Dispose is called this header will be diposed.</param>
/// <param name="octets">The octets to project</param>
public RtpPacket(RtpHeader header, IEnumerable <byte> octets, bool ownsHeader = true)
{
if (header == null)
{
throw new ArgumentNullException("header");
}
//Assign the header (maybe referenced elsewhere, when dispose is called the given header will be disposed.)
Header = header;
ShouldDispose = m_OwnsHeader = ownsHeader;
//Project the octets in the sequence
m_OwnedOctets = octets.ToArray();
//The Payload property must be assigned otherwise the properties will not function in the instance.
Payload = new MemorySegment(m_OwnedOctets, 0, m_OwnedOctets.Length);
}
/// <summary>
/// Generates a sequence of bytes containing the RtpHeader and any data contained in Payload.
/// (Including the SourceList and RtpExtension if present)
/// </summary>
/// <param name="other">The optional other RtpHeader to utilize in the preperation</param>
/// <returns>The sequence created.</returns>
public IEnumerable <byte> Prepare(RtpHeader other = null)
{
return(Enumerable.Concat <byte>(other ?? Header, Payload.Count > 0 ? Payload.Array.Skip(Payload.Offset).Take(Payload.Count) : Media.Common.MemorySegment.EmptyBytes));
}
/// <summary>
/// Given a packet using the redundant audio format, the expanded rtp packets are derived from the contents.
/// </summary>
/// <param name="packet"></param>
/// <param name="shouldDispose"></param>
/// <returns></returns>
public static System.Collections.Generic.IEnumerable <RtpPacket> GetPackets(RtpPacket packet, bool shouldDispose = true)
{
if (Common.IDisposedExtensions.IsNullOrDisposed(packet))
{
yield break;
}
int headerOctets = packet.HeaderOctets,
offset = packet.Payload.Offset + headerOctets, startOffset = offset,
remaining = packet.Payload.Count - (headerOctets + packet.PaddingOctets),
endHeaders = remaining, headersContained = 0;
//If there are not enough bytes for the profile header break.
if (remaining < Common.Binary.BytesPerInteger)
{
yield break;
}
byte toCheck;
//Iterare from the offset of the end of the rtp header until the end of data in the payload
while (remaining >= Common.Binary.BytesPerInteger)
{
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
//+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//|F| block PT | timestamp offset | block length |
//+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
toCheck = packet.Payload.Array[offset];
//Check for (F)irst bit
if ((toCheck & 0x80) != 0)
{
//Store the offset of the last header.
endHeaders = offset;
//This byte does not belong to the data.
--remaining;
break;
}
//Increment for the header contained.
++headersContained;
//Decrement for the header read.
remaining -= Common.Binary.BytesPerInteger;
//Move by 4 bytes beause the size of the header is 4 bytes.
offset += Common.Binary.BytesPerInteger;
}
//Nothing more to return
if (remaining < 0)
{
yield break;
}
Common.MemorySegment tempPayload;
Rtp.RtpHeader tempHeader;
RtpPacket tempResult;
int tempPayloadType, tempTimestamp, tempBlockLen;
bool marker = packet.Marker;
//Start at the offset in bits of the end of header.
if (headersContained > 0)
{
for (int headOffset = startOffset, i = 0, bitOffset = Common.Binary.BytesToBits(ref headOffset); i < headersContained; ++i)
{
//Read the payloadType out of the header
tempPayloadType = (int)Common.Binary.ReadBitsMSB(packet.Payload.Array, Common.Binary.BytesToBits(ref headOffset) + 1, 7);
//Read the timestamp offset from the header
tempTimestamp = (int)Common.Binary.ReadBitsMSB(packet.Payload.Array, ref bitOffset, 10);
//Read the blockLength from the header
tempBlockLen = (int)Common.Binary.ReadBitsMSB(packet.Payload.Array, ref bitOffset, 14);
//If there are less bytes in the payload than remain in the block stop
//if (remaining < tempBlockLen) break;
//Get the payload
Common.MemorySegment payload = new Common.MemorySegment(packet.Payload.Array, Common.Binary.BitsToBytes(ref bitOffset), tempBlockLen, shouldDispose);
//Create the header
Rtp.RtpHeader header = new RtpHeader(packet.Version, false, false, marker, tempPayloadType, 0, packet.SynchronizationSourceIdentifier,
packet.SequenceNumber,
packet.Timestamp + tempTimestamp,
shouldDispose);
//Create the packet
RtpPacket result = new RtpPacket(header, payload, shouldDispose);
//Return the packet
yield return(result);
//Move the offset
bitOffset += Common.Binary.BytesToBits(ref tempBlockLen);
//Remove the blockLength from the count
remaining -= tempBlockLen;
}
}
//If there is anymore data it's values are defined in the header of the given packet.
//Read the payloadType out of the headers area (1 bit after the end of headers) 7 bits in size
tempPayloadType = (int)Common.Binary.ReadBitsMSB(packet.Payload.Array, Common.Binary.BytesToBits(ref startOffset) + 1, 7);
//Get the payload of the temp packet, the blockLen is given by the count in this packet minus the
tempPayload = new Common.MemorySegment(packet.Payload.Array, endHeaders, remaining, shouldDispose);
//Create the header
tempHeader = new RtpHeader(packet.Version, false, false, marker, tempPayloadType, 0, packet.SynchronizationSourceIdentifier,
packet.SequenceNumber,
packet.Timestamp,
shouldDispose);
//Create the packet
tempResult = new RtpPacket(tempHeader, tempPayload, shouldDispose);
//Return the packet
yield return(tempResult);
}
public bool Equals(RtpHeader other)
{
return(other.First16Bits.Equals(First16Bits)
&&
other.SynchronizationSourceIdentifier.Equals(SynchronizationSourceIdentifier));
}
