gsmcodec.cxx

sloedgy open sip stack source code

/*
 * gsmcodec.cxx
 *
 * H.323 protocol handler
 *
 * Open H323 Library
 *
 * Copyright (c) 1998-2000 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Open H323 Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions of this code were written with the assisance of funding from
 * Vovida Networks, Inc. http://www.vovida.com.
 *
 * Contributor(s): ______________________________________.
 *
 * $Log: gsmcodec.cxx,v $
 * Revision 1.1  2006/06/26 03:02:34  joegenbaclor
 * I have decided to include the latest development realease  of OPAL tagged Deimos Devel 1 (June 8 2006) as inegrated classes to opensipstack to avoid future version conflicts due to the fast pace in OPAL development.   This move is also aimed to reduce the size of projects using OPAL componets such as the soon to be relased OpenSIPPhone.
 *
 * Revision 2.6  2006/02/14 22:37:14  csoutheren
 * Fixed error in adpative GSM calcs
 *
 * Revision 2.5  2006/02/09 22:48:40  csoutheren
 * Experimental fix for receiving MSGSM in GSM codec
 *
 * Revision 2.4  2005/08/28 07:59:17  rjongbloed
 * Converted OpalTranscoder to use factory, requiring sme changes in making sure
 *   OpalMediaFormat instances are initialised before use.
 *
 * Revision 2.3  2002/09/04 06:01:47  robertj
 * Updated to OpenH323 v1.9.6
 *
 * Revision 2.2  2001/10/05 00:22:13  robertj
 * Updated to PWLib 1.2.0 and OpenH323 1.7.0
 *
 * Revision 2.1  2001/08/01 05:04:28  robertj
 * Changes to allow control of linking software transcoders, use macros
 *   to force linking.
 * Allowed codecs to be used without H.,323 being linked by using the
 *   new NO_H323 define.
 * Major changes to H.323 capabilities, uses OpalMediaFormat for base name.
 *
 * Revision 2.0  2001/07/27 15:48:24  robertj
 * Conversion of OpenH323 to Open Phone Abstraction Library (OPAL)
 *
 * Revision 1.21  2002/08/05 10:03:47  robertj
 * Cosmetic changes to normalise the usage of pragma interface/implementation.
 *
 * Revision 1.20  2001/09/21 02:51:06  robertj
 * Implemented static object for all "known" media formats.
 *
 * Revision 1.19  2001/05/14 05:56:28  robertj
 * Added H323 capability registration system so can add capabilities by
 *   string name instead of having to instantiate explicit classes.
 *
 * Revision 1.18  2001/02/09 05:13:55  craigs
 * Added pragma implementation to (hopefully) reduce the executable image size
 * under Linux
 *
 * Revision 1.17  2001/01/25 07:27:16  robertj
 * Major changes to add more flexible OpalMediaFormat class to normalise
 *   all information about media types, especially codecs.
 *
 * Revision 1.16  2000/10/13 03:43:29  robertj
 * Added clamping to avoid ever setting incorrect tx frame count.
 *
 * Revision 1.15  2000/08/25 03:18:40  craigs
 * More work on support for MS-GSM format
 *
 * Revision 1.14  2000/07/13 17:24:33  robertj
 * Fixed format name to be consistent will all others.
 *
 * Revision 1.13  2000/07/12 10:25:37  robertj
 * Renamed all codecs so obvious whether software or hardware.
 *
 * Revision 1.12  2000/07/09 14:55:15  robertj
 * Bullet proofed packet count so incorrect capabilities does not crash us.
 *
 * Revision 1.11  2000/05/10 04:05:33  robertj
 * Changed capabilities so has a function to get name of codec, instead of relying on PrintOn.
 *
 * Revision 1.10  2000/05/02 04:32:26  robertj
 * Fixed copyright notice comment.
 *
 * Revision 1.9  2000/03/21 03:06:49  robertj
 * Changes to make RTP TX of exact numbers of frames in some codecs.
 *
 * Revision 1.8  1999/12/31 00:05:36  robertj
 * Added Microsoft ACM G.723.1 codec capability.
 *
 * Revision 1.7  1999/11/20 00:53:47  robertj
 * Fixed ability to have variable sized frames in single RTP packet under G.723.1
 *
 * Revision 1.6  1999/10/08 09:59:03  robertj
 * Rewrite of capability for sending multiple audio frames
 *
 * Revision 1.5  1999/10/08 08:30:45  robertj
 * Fixed maximum packet size, must be less than 256
 *
 * Revision 1.4  1999/10/08 04:58:38  robertj
 * Added capability for sending multiple audio frames in single RTP packet
 *
 * Revision 1.3  1999/09/27 01:13:09  robertj
 * Fixed old GNU compiler support
 *
 * Revision 1.2  1999/09/23 07:25:12  robertj
 * Added open audio and video function to connection and started multi-frame codec send functionality.
 *
 * Revision 1.1  1999/09/08 04:05:49  robertj
 * Added support for video capabilities & codec, still needs the actual codec itself!
 *
 */

#include <ptlib.h>

#ifdef __GNUC__
#pragma implementation "gsmcodec.h"
#endif

#include <codec/gsmcodec.h>

extern "C" {
#include "gsm/inc/gsm.h"
};


#define new PNEW


#define GSM_BYTES_PER_FRAME   33
#define GSM_SAMPLES_PER_FRAME 160


///////////////////////////////////////////////////////////////////////////////

Opal_GSM0610::Opal_GSM0610(const OpalMediaFormat & inputMediaFormat,
                           const OpalMediaFormat & outputMediaFormat,
                           unsigned inputBytesPerFrame,
                           unsigned outputBytesPerFrame)
  : OpalFramedTranscoder(inputMediaFormat, outputMediaFormat, inputBytesPerFrame, outputBytesPerFrame)
{
  gsm = gsm_create();
}


Opal_GSM0610::~Opal_GSM0610()
{
  gsm_destroy(gsm);
}


///////////////////////////////////////////////////////////////////////////////

Opal_GSM0610_PCM::Opal_GSM0610_PCM()
  : Opal_GSM0610(OpalGSM0610, OpalPCM16, GSM_BYTES_PER_FRAME, GSM_SAMPLES_PER_FRAME*2)
{
  PTRACE(3, "Codec\tGSM0610 decoder created");
}

/*
 * this code attempts to detect the type of the incoming frame, i.e. whether it is formatted as a GSM packets
 * or whether it uses the MS-GSM packetization (also knows as WAV49)
 */
BOOL Opal_GSM0610_PCM::Convert(const RTP_DataFrame & input, RTP_DataFrame & output)
{
  const BYTE * inputPtr = input.GetPayloadPtr();
  PINDEX inputLength = input.GetPayloadSize();
  BYTE * outputPtr = output.GetPayloadPtr();

  if (inputLength == 0) {
    output.SetPayloadSize(outputBytesPerFrame);
    return ConvertSilentFrame (outputPtr);
  }

  // Unless the packet is 65 bytes long, it must be normal GSM
  if (inputLength != 65) {
    int opt = 0;
    gsm_option(gsm, GSM_OPT_WAV49, &opt);
    return OpalFramedTranscoder::Convert(input, output);
  }

  // MS-GSM packets are always 65 bytes long, and consists of two GSM packets

  // put encoder into WAV49 mode
  int opt = 1;
  gsm_option(gsm, GSM_OPT_WAV49, &opt);
  
  output.SetPayloadSize(2*outputBytesPerFrame);

  // decode the first frame 
  gsm_decode(gsm, (gsm_byte *)inputPtr,    (gsm_signal *)outputPtr);

  // decode the second frame 
  gsm_decode(gsm, (gsm_byte *)inputPtr+33, (gsm_signal *)outputPtr+GSM_SAMPLES_PER_FRAME);

  return TRUE;
}

BOOL Opal_GSM0610_PCM::ConvertFrame(const BYTE * src, BYTE * dst)
{
  gsm_decode(gsm, (gsm_byte *)src, (gsm_signal *)dst);
  return TRUE;
}


///////////////////////////////////////////////////////////////////////////////

Opal_PCM_GSM0610::Opal_PCM_GSM0610()
  : Opal_GSM0610(OpalPCM16, OpalGSM0610, GSM_SAMPLES_PER_FRAME*2, GSM_BYTES_PER_FRAME)
{
  PTRACE(3, "Codec\tGSM0610 encoder created");
}


BOOL Opal_PCM_GSM0610::ConvertFrame(const BYTE * src, BYTE * dst)
{
  gsm_encode(gsm, (gsm_signal *)src, (gsm_byte *)dst);
  return TRUE;
}


/////////////////////////////////////////////////////////////////////////////