liveMedia/include/VorbisAudioRTPSink.hh

/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)

This library is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
more details.

You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
**********/
// "liveMedia"
// Copyright (c) 1996-2020 Live Networks, Inc.  All rights reserved.
// RTP sink for Vorbis audio
// C++ header

#ifndef _VORBIS_AUDIO_RTP_SINK_HH
#define _VORBIS_AUDIO_RTP_SINK_HH

#ifndef _AUDIO_RTP_SINK_HH
#include "AudioRTPSink.hh"
#endif

class VorbisAudioRTPSink: public AudioRTPSink {
public:
  static VorbisAudioRTPSink*
  createNew(UsageEnvironment& env, Groupsock* RTPgs, u_int8_t rtpPayloadFormat,
	    u_int32_t rtpTimestampFrequency, unsigned numChannels,
	    // The following headers provide the 'configuration' information, for the SDP description:
	    u_int8_t* identificationHeader, unsigned identificationHeaderSize,
	    u_int8_t* commentHeader, unsigned commentHeaderSize,
	    u_int8_t* setupHeader, unsigned setupHeaderSize,
	    u_int32_t identField = 0xFACADE);

  static VorbisAudioRTPSink*
  createNew(UsageEnvironment& env, Groupsock* RTPgs, u_int8_t rtpPayloadFormat,
	    u_int32_t rtpTimestampFrequency, unsigned numChannels,
	    char const* configStr);
    // an optional variant of "createNew()" that takes a Base-64-encoded 'configuration' string,
    // rather than the raw configuration headers as parameter.

protected:
  VorbisAudioRTPSink(UsageEnvironment& env, Groupsock* RTPgs,
		     u_int8_t rtpPayloadFormat, u_int32_t rtpTimestampFrequency, unsigned numChannels,
		     u_int8_t* identificationHeader, unsigned identificationHeaderSize,
		     u_int8_t* commentHeader, unsigned commentHeaderSize,
		     u_int8_t* setupHeader, unsigned setupHeaderSize,
		     u_int32_t identField);
	// called only by createNew()

  virtual ~VorbisAudioRTPSink();

private: // redefined virtual functions:
  virtual char const* auxSDPLine(); // for the "a=fmtp:" SDP line

  virtual void doSpecialFrameHandling(unsigned fragmentationOffset,
                                      unsigned char* frameStart,
                                      unsigned numBytesInFrame,
                                      struct timeval framePresentationTime,
                                      unsigned numRemainingBytes);
  virtual Boolean frameCanAppearAfterPacketStart(unsigned char const* frameStart,
						 unsigned numBytesInFrame) const;
  virtual unsigned specialHeaderSize() const;
  virtual unsigned frameSpecificHeaderSize() const;

private:
  u_int32_t fIdent; // "Ident" field used by this stream.  (Only the low 24 bits of this are used.)
  char* fFmtpSDPLine;
};


// A general function used by both "VorbisAudioRTPSink" and "TheoraVideoRTPSink" to construct
// a Base64-encoded 'config' string (for SDP) from "identification", "comment", "setup" headers.
// (Note: The result string was heap-allocated, and the caller should delete[] it afterwards.)

char* generateVorbisOrTheoraConfigStr(u_int8_t* identificationHeader, unsigned identificationHeaderSize,
				      u_int8_t* commentHeader, unsigned commentHeaderSize,
				      u_int8_t* setupHeader, unsigned setupHeaderSize,
				      u_int32_t identField);

#endif