public AudioListener(IRtspReceiver receiver, string sessionId, ushort cport, ushort dport, CodecLibrariesConfig clConfig, DumpConfig dConfig) : base(cport, dport)
{
_receiver = receiver ?? throw new ArgumentNullException(nameof(receiver));
_sessionId = sessionId ?? throw new ArgumentNullException(nameof(sessionId));
_clConfig = clConfig ?? throw new ArgumentNullException(nameof(clConfig));
_dConfig = dConfig ?? throw new ArgumentNullException(nameof(dConfig));
_raopBuffer = RaopBufferInit();
_aesCbcDecrypt = CipherUtilities.GetCipher("AES/CBC/NoPadding");
}
private void RaopBufferFlush(RaopBuffer raop_buffer, int next_seq)
{
int i;
for (i = 0; i < RAOP_BUFFER_LENGTH; i++)
{
raop_buffer.Entries[i].Available = false;
raop_buffer.Entries[i].AudioBufferLen = 0;
}
if (next_seq < 0 || next_seq > 0xffff)
{
raop_buffer.IsEmpty = true;
}
else
{
raop_buffer.FirstSeqNum = (ushort)next_seq;
raop_buffer.LastSeqNum = (ushort)(next_seq - 1);
}
}
private RaopBuffer RaopBufferInit()
{
var audio_buffer_size = 480 * 4;
var raop_buffer = new RaopBuffer();
raop_buffer.BufferSize = audio_buffer_size * RAOP_BUFFER_LENGTH;
raop_buffer.Buffer = new byte[raop_buffer.BufferSize];
for (int i = 0; i < RAOP_BUFFER_LENGTH; i++)
{
var entry = raop_buffer.Entries[i];
entry.AudioBufferSize = audio_buffer_size;
entry.AudioBufferLen = 0;
entry.AudioBuffer = (byte[])raop_buffer.Buffer.Skip(i).Take(audio_buffer_size).ToArray();
raop_buffer.Entries[i] = entry;
}
raop_buffer.IsEmpty = true;
return(raop_buffer);
}
private void RaopBufferHandleResends(RaopBuffer raop_buffer, Socket cSocket, ushort control_seqnum)
{
RaopBufferEntry entry;
if (Utilities.SeqNumCmp(raop_buffer.FirstSeqNum, raop_buffer.LastSeqNum) < 0)
{
int seqnum, count;
for (seqnum = raop_buffer.FirstSeqNum; Utilities.SeqNumCmp(seqnum, raop_buffer.LastSeqNum) < 0; seqnum++)
{
entry = raop_buffer.Entries[seqnum % RAOP_BUFFER_LENGTH];
if (entry.Available)
{
break;
}
}
if (Utilities.SeqNumCmp(seqnum, raop_buffer.FirstSeqNum) == 0)
{
return;
}
count = Utilities.SeqNumCmp(seqnum, raop_buffer.FirstSeqNum);
RaopRtpResendCallback(cSocket, control_seqnum, raop_buffer.FirstSeqNum, (ushort)count);
}
}
public byte[] RaopBufferDequeue(RaopBuffer raop_buffer, ref int length, ref uint pts, bool noResend)
{
short buflen;
RaopBufferEntry entry;
/* Calculate number of entries in the current buffer */
buflen = (short)(raop_buffer.LastSeqNum - raop_buffer.FirstSeqNum + 1);
/* Cannot dequeue from empty buffer */
if (raop_buffer.IsEmpty || buflen <= 0)
{
return(null);
}
/* Get the first buffer entry for inspection */
entry = raop_buffer.Entries[raop_buffer.FirstSeqNum % RAOP_BUFFER_LENGTH];
if (noResend)
{
/* If we do no resends, always return the first entry */
entry.Available = false;
/* Return entry audio buffer */
length = entry.AudioBufferLen;
pts = entry.TimeStamp;
entry.AudioBufferLen = 0;
raop_buffer.Entries[raop_buffer.FirstSeqNum % RAOP_BUFFER_LENGTH] = entry;
raop_buffer.FirstSeqNum += 1;
return(entry.AudioBuffer);
}
else if (!entry.Available)
{
/* Check how much we have space left in the buffer */
if (buflen < RAOP_BUFFER_LENGTH)
{
/* Return nothing and hope resend gets on time */
length = entry.AudioBufferSize;
Array.Fill <byte>(entry.AudioBuffer, 0, 0, length);
return(entry.AudioBuffer);
}
/* Risk of buffer overrun, return empty buffer */
return(Array.Empty <byte>());
}
/* Update buffer and validate entry */
if (!entry.Available)
{
/* Return an empty audio buffer to skip audio */
length = entry.AudioBufferSize;
Array.Fill <byte>(entry.AudioBuffer, 0, 0, length);
return(entry.AudioBuffer);
}
entry.Available = false;
/* Return entry audio buffer */
length = entry.AudioBufferLen;
pts = entry.TimeStamp;
entry.AudioBufferLen = 0;
raop_buffer.Entries[raop_buffer.FirstSeqNum % RAOP_BUFFER_LENGTH] = entry;
raop_buffer.FirstSeqNum += 1;
return(entry.AudioBuffer.Take(length).ToArray());
}
public int RaopBufferQueue(RaopBuffer raop_buffer, byte[] data, ushort datalen, Session session)
{
int encryptedlen;
RaopBufferEntry entry;
/* Check packet data length is valid */
if (datalen < 12 || datalen > RAOP_PACKET_LENGTH)
{
return(-1);
}
var seqnum = (ushort)((data[2] << 8) | data[3]);
if (datalen == 16 && data[12] == 0x0 && data[13] == 0x68 && data[14] == 0x34 && data[15] == 0x0)
{
return(0);
}
// Ignore, old
if (!raop_buffer.IsEmpty && seqnum < raop_buffer.FirstSeqNum && seqnum != 0)
{
return(0);
}
/* Check that there is always space in the buffer, otherwise flush */
if (raop_buffer.FirstSeqNum + RAOP_BUFFER_LENGTH < seqnum || seqnum == 0)
{
RaopBufferFlush(raop_buffer, seqnum);
}
entry = raop_buffer.Entries[seqnum % RAOP_BUFFER_LENGTH];
if (entry.Available && entry.SeqNum == seqnum)
{
/* Packet resent, we can safely ignore */
return(0);
}
entry.Flags = data[0];
entry.Type = data[1];
entry.SeqNum = seqnum;
entry.TimeStamp = (uint)((data[4] << 24) | (data[5] << 16) | (data[6] << 8) | data[7]);
entry.SSrc = (uint)((data[8] << 24) | (data[9] << 16) | (data[10] << 8) | data[11]);
entry.Available = true;
int payloadsize = datalen - 12;
var raw = new byte[payloadsize];
encryptedlen = payloadsize / 16 * 16;
if (encryptedlen > 0)
{
_aesCbcDecrypt.ProcessBytes(data, 12, encryptedlen, data, 12);
Array.Copy(data, 12, raw, 0, encryptedlen);
}
Array.Copy(data, 12 + encryptedlen, raw, encryptedlen, payloadsize - encryptedlen);
#if DUMP
/* RAW -> DUMP */
var fPath = Path.Combine(_dConfig.Path, "frames/");
File.WriteAllBytes($"{fPath}raw_{seqnum}", raw);
#endif
/* RAW -> PCM */
var length = _decoder.GetOutputStreamLength();
var output = new byte[length];
var res = _decoder.DecodeFrame(raw, ref output, length);
if (res != 0)
{
output = new byte[length];
Console.WriteLine($"Decoding error. Decoder: {_decoder.Type} Code: {res}");
}
#if DUMP
var pPath = Path.Combine(_dConfig.Path, "pcm/");
Console.WriteLine($"RES: {res}");
Console.WriteLine($"PCM: {output.Length}");
Console.WriteLine($"LNG: {length}");
File.WriteAllBytes($"{pPath}raw_{seqnum}", output);
#endif
Array.Copy(output, 0, entry.AudioBuffer, 0, output.Length);
entry.AudioBufferLen = output.Length;
/* Update the raop_buffer seqnums */
if (raop_buffer.IsEmpty)
{
raop_buffer.FirstSeqNum = seqnum;
raop_buffer.LastSeqNum = seqnum;
raop_buffer.IsEmpty = false;
}
if (raop_buffer.LastSeqNum < seqnum)
{
raop_buffer.LastSeqNum = seqnum;
}
// Update entries
raop_buffer.Entries[seqnum % RAOP_BUFFER_LENGTH] = entry;
return(1);
}
