public List <Nalu> ToRTP(PSFragment ps)
{
if (ps.IsFrameStart)
{
_header = ps.Header;
}
if (_header == null)
{
return(new List <Nalu>());
}
List <Nalu> nList = new List <Nalu>();
if (ps.Data.Length < MTU && ps.IsFrameStart && ps.IsFrameEnd)
{
nList.Add(new Nalu(_header, ps.Data));
}
else
{
List <byte[]> slices = SplitPayload(ps.Data);
NaluHeader indicator = new NaluHeader(false, _header.NRI, NaluTypes.FU_A);
for (int i = 0; i < slices.Count; i++)
{
bool start = (i == 0) && ps.IsFrameStart;
bool end = (i == slices.Count - 1 && ps.IsFrameEnd);
FuHeader fuh = new FuHeader(start, end, _header.Type);
nList.Add(new FragUnitA(indicator, fuh, slices[i]).ToNalu());
}
}
return(nList);
}
public FragUnitA(NaluHeader indicator, FuHeader header, byte[] payload)
{
Indicator = indicator;
if (indicator.Type != NALU_TYPE)
{
throw new ArgumentException($"FU-B封包的指示字节的类型必须是{NALU_TYPE}", nameof(indicator));
}
Header = header;
Payload = payload;
}
public static FuHeader Parse(byte data)
{
FuHeader fh = new FuHeader();
fh.IsStart = ((data & 0x80) >> 7) == 1;
fh.IsEnd = ((data & 0x40) >> 6) == 1;
fh.Type = (data & 0x1F);
fh._data = data;
return(fh);
}
public FragUnitB(NaluHeader indicator, FuHeader header, short don, byte[] payload)
{
if (indicator.Type != NALU_TYPE)
{
throw new ArgumentException($"FU-B封包的指示字节的类型必须是{NALU_TYPE}", nameof(indicator));
}
Indicator = indicator;
Header = header;
Don = don;
Payload = payload;
}
public static FragUnitA Parse(byte[] data)
{
FragUnitA fu = new FragUnitA();
fu.Indicator = NaluHeader.Parse(data[0]);
if (fu.Indicator.Type != NALU_TYPE)
{
throw new ArgumentException($"FU-B封包的指示字节的类型必须是{NALU_TYPE}，当前类型是:" + fu.Indicator.Type);
}
fu.Header = FuHeader.Parse(data[1]);
fu.Payload = BytesHelper.SubBytes(data, 2);
return(fu);
}
public static FragUnitB Parse(byte[] data)
{
FragUnitB fu = new FragUnitB();
fu.Indicator = NaluHeader.Parse(data[0]);
if (fu.Indicator.Type != NALU_TYPE)
{
throw new ArgumentException($"FU-B封包的指示字节的类型必须是{NALU_TYPE}，当前类型是:" + fu.Indicator.Type);
}
fu.Header = FuHeader.Parse(data[1]);
//TODO:我们暂时认为所有的字节序均为BigEndian,如果传输失败，再做改正。
byte[] donBytes = new byte[] { data[3], data[2] };
fu.Don = BitConverter.ToInt16(donBytes, 0);
fu.Payload = BytesHelper.SubBytes(data, 4);
return(fu);
}
public static List <Nalu> ToRTPPayload(Nalu src)
{
List <Nalu> nList = new List <Nalu>();
if (src.TotalBytes < MTU)
{
nList.Add(src);
}
else
{
List <byte[]> slices = SplitPayload(src);
NaluHeader indicator = new NaluHeader(false, src.Header.NRI, NaluTypes.FU_A);
for (int i = 0; i < slices.Count; i++)
{
bool start = i == 0;
bool end = i == slices.Count - 1;
FuHeader fuh = new FuHeader(start, end, src.Header.Type);
nList.Add(new FragUnitA(indicator, fuh, slices[i]).ToNalu());
}
}
return(nList);
}
