lpc10codec.cxx

sloedgy open sip stack source code

/*
 * lpc10codec.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.
 *
 * Contributor(s): ______________________________________.
 *
 * $Log: lpc10codec.cxx,v $
 * Revision 1.1  2006/06/26 03:02:35  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 2.9  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 2.8  2005/02/21 12:19:54  rjongbloed
 * Added new "options list" to the OpalMediaFormat class.
 *
 * Revision 2.7  2004/09/01 12:21:27  rjongbloed
 * Added initialisation of H323EndPoints capability table to be all codecs so can
 *   correctly build remote caps from fqast connect params. This had knock on effect
 *   with const keywords added in numerous places.
 *
 * Revision 2.6  2004/02/19 10:47:02  rjongbloed
 * Merged OpenH323 version 1.13.1 changes.
 *
 * Revision 2.5  2002/11/10 11:33:18  robertj
 * Updated to OpenH323 v1.10.3
 *
 * Revision 2.4  2002/09/04 06:01:47  robertj
 * Updated to OpenH323 v1.9.6
 *
 * Revision 2.3  2002/01/22 05:19:27  robertj
 * Added RTP encoding name string to media format database.
 * Changed time units to clock rate in Hz.
 *
 * 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 1.11  2003/06/05 23:44:20  rjongbloed
 * Minor optimisations. Extremely minor.
 *
 * Revision 1.10  2003/04/27 23:51:19  craigs
 * Fixed possible problem with context deletion
 *
 * Revision 1.9  2002/09/03 06:01:16  robertj
 * Added globally accessible functions for media format name.
 *
 * Revision 1.8  2002/08/05 10:03:48  robertj
 * Cosmetic changes to normalise the usage of pragma interface/implementation.
 *
 * Revision 1.7  2001/09/21 02:51:29  robertj
 * Added default session ID to media format description.
 *
 * Revision 1.6  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 1.5  2001/02/09 05:13:56  craigs
 * Added pragma implementation to (hopefully) reduce the executable image size
 * under Linux
 *
 * Revision 1.4  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 1.3  2000/07/12 10:25:37  robertj
 * Renamed all codecs so obvious whether software or hardware.
 *
 * Revision 1.2  2000/06/17 04:09:49  craigs
 * Fixed problem with (possibly bogus) underrun errors being reported in debug mode
 *
 * Revision 1.1  2000/06/05 04:45:11  robertj
 * Added LPC-10 2400bps codec
 *
 */

#include <ptlib.h>

#ifdef __GNUC__
#pragma implementation "lpc10codec.h"
#endif

#include <codec/lpc10codec.h>

extern "C" {
#include "lpc10/lpc10.h"
};


#define new PNEW


enum {
  SamplesPerFrame = 180,    // 22.5 milliseconds
  BitsPerFrame = 54,        // Encoded size
  BytesPerFrame = (BitsPerFrame+7)/8
};

const real SampleValueScale = 32768.0;
const real MaxSampleValue = 32767.0;
const real MinSampleValue = -32767.0;


const OpalAudioFormat & GetOpalLPC10()
{
  static const OpalAudioFormat LPC10(
    OPAL_LPC10,
    RTP_DataFrame::LPC,
    "LPC",
    BytesPerFrame,
    SamplesPerFrame,
    7, 4
  );
  return LPC10;
}


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

#ifndef NO_H323

H323_LPC10Capability::H323_LPC10Capability(const H323EndPoint & endpoint)
  : H323NonStandardAudioCapability(endpoint,
                                   (const BYTE *)(const char *)OpalLPC10,
                                   OpalLPC10.GetLength())
{
}


PObject * H323_LPC10Capability::Clone() const
{
  return new H323_LPC10Capability(*this);
}


PString H323_LPC10Capability::GetFormatName() const
{
  return OpalLPC10;
}


#endif


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

Opal_LPC10_PCM::Opal_LPC10_PCM()
  : OpalFramedTranscoder(OpalLPC10, OpalPCM16, BytesPerFrame, SamplesPerFrame*2)
{
  decoder = (struct lpc10_decoder_state *)malloc((unsigned)sizeof(struct lpc10_decoder_state));
  ::init_lpc10_decoder_state(decoder);
  PTRACE(3, "Codec\tLPC-10 decoder created");
}


Opal_LPC10_PCM::~Opal_LPC10_PCM()
{
  if (decoder != NULL)
    free(decoder);
}
 

BOOL Opal_LPC10_PCM::ConvertFrame(const BYTE * src, BYTE * dst)
{
  PINDEX i;

  INT32 bits[BitsPerFrame];
  for (i = 0; i < BitsPerFrame; i++)
    bits[i] = (src[i>>3]&(1<<(i&7))) != 0;

  real speech[SamplesPerFrame];
  lpc10_decode(bits, speech, decoder);

  for (i = 0; i < SamplesPerFrame; i++) {
    real sample = speech[i]*SampleValueScale;
    if (sample < MinSampleValue)
      sample = MinSampleValue;
    else if (sample > MaxSampleValue)
      sample = MaxSampleValue;
    ((short *)dst)[i] = (short)sample;
  }

  return TRUE;
}


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

Opal_PCM_LPC10::Opal_PCM_LPC10()
  : OpalFramedTranscoder(OpalPCM16, OpalLPC10, SamplesPerFrame*2, BytesPerFrame)
{
  encoder = (struct lpc10_encoder_state *)malloc((unsigned)sizeof(struct lpc10_encoder_state));
  ::init_lpc10_encoder_state(encoder);
  PTRACE(3, "Codec\tLPC-10 encoder created");
}


Opal_PCM_LPC10::~Opal_PCM_LPC10()
{
  if (encoder != NULL)
    free(encoder);
}
 

BOOL Opal_PCM_LPC10::ConvertFrame(const BYTE * src, BYTE * dst)
{
  PINDEX i;

  real speech[SamplesPerFrame];
  for (i = 0; i < SamplesPerFrame; i++)
    speech[i] = ((short *)src)[i]/SampleValueScale;

  INT32 bits[BitsPerFrame];
  lpc10_encode(speech, bits, encoder);

  memset(dst, 0, BytesPerFrame);
  for (i = 0; i < BitsPerFrame; i++) {
    if (bits[i])
      dst[i>>3] |= 1 << (i&7);
  }

  return TRUE;
}


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