protected virtual int FindTSHeadFlag(byte[] data)
{
var ms = new MemoryStream(data);
TSProgramManage tsms = new TSProgramManage();
int pos = 0;
while (pos++ < data.Length)
{
var index = ms.Position;
if (ms.ReadByte() == 0x47)
{
int offset = (int)ms.Position - 1;
if (!CheckOffsetIsPacketFlag(data, offset))
{
continue;
}
ms.Seek(-1, SeekOrigin.Current);
byte[] buf = new byte[188];
ms.Read(buf, 0, buf.Length);
try {
TSPacket pack = new TSPacket()
{
ProgramManage = tsms
};
pack.SetBytes(buf);
pack.Decode();
ms.Seek(-188, SeekOrigin.Current);
return((int)ms.Position);
break;
} catch (Exception e) {
return(-1);
}
}
}
return(-1);
}
protected virtual void TSStreamResolveThread()
{
byte[] buffer_ts = new byte[188 * 2]; //两个包的空间，这里需要读取两个188字节的ts packet 而不是读取一个的原因是，
//读取两个，当可以检验前后ts packet标识字段是否为0x47，如果不是则当前位置不是处理ts packet的开头，
//则需要重新找到ts packet的头
byte[] part_ts = null;//当检测到当前ts packet错误的时候 part_ts用来保存正确的ts packet中的一部分
while (_isworking)
{
int readSize = 188 * 2 - (part_ts != null ? part_ts.Length : 0);//如果上一次没有残留数据则长度为 2个ts packet 的长度
if (_ioStream.Length >= readSize)
{
if (part_ts != null)
{
Array.Copy(part_ts, 0, buffer_ts, 0, part_ts.Length); //残留数据
}
_ioStream.Read(buffer_ts, buffer_ts.Length - readSize, readSize); //读取到缓冲区
if (buffer_ts[0] != 0x47)
{
//当前为非 ts packet的头，则找到下一个ts packet的头的偏移
int offset = FindTSHeadFlag(buffer_ts);
if (offset == -1)//没有找到头则返回起点
{
continue;
}
//从2*188字节中减去偏移，再减去一个ts packet的长度得到残余的数据长度
part_ts = new byte[buffer_ts.Length - 188 - offset];
Array.Copy(buffer_ts, offset + 188, part_ts, 0, part_ts.Length);
//新建一个临时的缓冲区，并将完整 的ts数据copy到这个临时缓冲区中
var tmp_buffer = new byte[188];
Array.Copy(buffer_ts, offset, tmp_buffer, 0, tmp_buffer.Length);
try {
TSPacket pack = new TSPacket()
{
ProgramManage = _tsms
};
pack.SetBytes(tmp_buffer);
pack.Decode();
if (pack.PacketType == TSPacketType.DATA)
{
pack.ProgramManage.WriteMediaTSPacket(pack);
}
} catch (Exception e) {
_DebugEx.Trace("TSStreamInput", "解析TS失败 1" + e.ToString());
}
}
else
{
//当前为 ts packet的头，则找到下一个ts packet的头的偏移
try {
//判断前后两个ts packet是否开头均正确
if (buffer_ts[0] == 0x47 && buffer_ts[188] == 0x47)
{
//将两个ts packet 分别解析
var tmp_buffer = new byte[188];
Array.Copy(buffer_ts, 0, tmp_buffer, 0, tmp_buffer.Length);
TSPacket pack = new TSPacket()
{
ProgramManage = _tsms
};
pack.SetBytes(tmp_buffer);
pack.Decode();
if (pack.PacketType == TSPacketType.DATA)
{
pack.ProgramManage.WriteMediaTSPacket(pack);
}
Array.Copy(buffer_ts, 188, tmp_buffer, 0, tmp_buffer.Length);
pack = new TSPacket()
{
ProgramManage = _tsms
};
pack.SetBytes(tmp_buffer);
pack.Decode();
if (pack.PacketType == TSPacketType.DATA)
{
pack.ProgramManage.WriteMediaTSPacket(pack);
}
}
else
{
_DebugEx.Trace("TSStreamInput", "TS Packet HeadFlag Error");
throw new Exception("TS Packet HeadFlag Error");
}
} catch (Exception e) {
_DebugEx.Trace("TSStreamInput", "解析TS失败 2" + e.ToString());
}
part_ts = null;
}
}
else
{
Thread.Sleep(10);
}
}
}