path: root/libMpegTPEnc/src/tpenc_latm.cpp

/*****************************  MPEG-4 AAC Encoder  **************************

                        (C) Copyright Fraunhofer IIS (2001)
                               All Rights Reserved

    Please be advised that this software and/or program delivery is
    Confidential Information of Fraunhofer and subject to and covered by the

    Fraunhofer IIS Software Evaluation Agreement
    between Google Inc. and  Fraunhofer
    effective and in full force since March 1, 2012.

    You may use this software and/or program only under the terms and
    conditions described in the above mentioned Fraunhofer IIS Software
    Evaluation Agreement. Any other and/or further use requires a separate agreement.


   $Id$
   Author(s):
   Description:

   This software and/or program is protected by copyright law and international
   treaties. Any reproduction or distribution of this software and/or program,
   or any portion of it, may result in severe civil and criminal penalties, and
   will be prosecuted to the maximum extent possible under law.

******************************************************************************/

#include "tpenc_latm.h"


#include "genericStds.h"

static const short celpFrameLengthTable[64] = {
 154, 170, 186, 147, 156, 165, 114, 120,
 186, 126, 132, 138, 142, 146, 154, 166,
 174, 182, 190, 198, 206, 210, 214, 110,
 114, 118, 120, 122, 218, 230, 242, 254,
 266, 278, 286, 294, 318, 342, 358, 374,
 390, 406, 422, 136, 142, 148, 154, 160,
 166, 170, 174, 186, 198, 206, 214, 222,
 230, 238, 216, 160, 280, 338, 0,   0
};

/*******
 write value to transport stream
 first two bits define the size of the value itself
 then the value itself, with a size of 0-3 bytes
*******/
static
UINT transportEnc_LatmWriteValue(HANDLE_FDK_BITSTREAM hBs, int value)
{
  UCHAR valueBytes = 4;
  unsigned int bitsWritten = 0;
  int i;

  if ( value < (1<<8) ) {
    valueBytes = 1;
  } else if ( value < (1<<16) ) {
    valueBytes = 2;
  } else if ( value < (1<<24) ) {
    valueBytes = 3;
  } else {
    valueBytes = 4;
  }

  FDKwriteBits(hBs, valueBytes-1, 2 ); /* size of value in Bytes */
  for (i=0; i<valueBytes; i++) {
    /* write most significant Byte first */
    FDKwriteBits(hBs, (UCHAR)(value>>((valueBytes-1-i)<<3)), 8);
  }

  bitsWritten = (valueBytes<<3)+2;

  return bitsWritten;
}

static
UINT transportEnc_LatmCountFixBitDemandHeader ( HANDLE_LATM_STREAM hAss )
{
  int bitDemand = 0;
  int insertSetupData = 0 ;

  /* only if start of new latm frame */
  if (hAss->subFrameCnt==0)
  {
    /* AudioSyncStream */

    if (hAss->tt == TT_MP4_LOAS) {
      bitDemand += 11 ;             /* syncword */
      bitDemand += 13 ;             /* audioMuxLengthBytes */
    }

    /* AudioMuxElement*/

    /* AudioMuxElement::Stream Mux Config */
    if (hAss->muxConfigPeriod > 0) {
      insertSetupData = (hAss->latmFrameCounter == 0);
    } else {
      insertSetupData = 0;
    }

    if (hAss->tt != TT_MP4_LATM_MCP0) {
      /* AudioMuxElement::useSameStreamMux Flag */
      bitDemand+=1;

      if( insertSetupData ) {
        bitDemand += hAss->streamMuxConfigBits;
      }
    }

    /* AudioMuxElement::otherDataBits */
    bitDemand += 8*hAss->otherDataLenBytes;

    /* AudioMuxElement::ByteAlign */
    if ( bitDemand % 8 ) {
       hAss->fillBits = 8 - (bitDemand % 8);
       bitDemand += hAss->fillBits ;
    } else {
      hAss->fillBits = 0;
    }
  }

  return bitDemand ;
}

static
UINT transportEnc_LatmCountVarBitDemandHeader ( HANDLE_LATM_STREAM hAss , unsigned int streamDataLength )
{
  int bitDemand = 0;
  int  prog, layer;

  /* Payload Length Info*/
  if( hAss->allStreamsSameTimeFraming ) {
    for( prog=0; prog<hAss->noProgram; prog++ ) {
      for( layer=0; layer<LATM_MAX_LAYERS; layer++ ) {
        LATM_LAYER_INFO *p_linfo = &(hAss->m_linfo[prog][layer]);

        if( p_linfo->streamID >= 0 ) {
          switch( p_linfo->frameLengthType ) {
          case 0:
            if ( streamDataLength > 0 ) {
              streamDataLength -= bitDemand ;
              while( streamDataLength >= (255<<3) ) {
                bitDemand+=8;
                streamDataLength -= (255<<3);
              }
              bitDemand += 8;
            }
            break;

          case 1:
          case 4:
          case 6:
            bitDemand += 2;
            break;

          default:
            return 0;
          }
        }
      }
    }
  } else {
    /* there are many possibilities to use this mechanism.  */
    switch( hAss->varMode ) {
    case LATMVAR_SIMPLE_SEQUENCE: {
      /* Use the sequence generated by the encoder */
      //int streamCntPosition = transportEnc_SetWritePointer( hAss->hAssemble, 0 );
      //int streamCntPosition = FDKgetValidBits( hAss->hAssemble );
      bitDemand+=4;

      hAss->varStreamCnt = 0;
      for( prog=0; prog<hAss->noProgram; prog++ ) {
        for( layer=0; layer<LATM_MAX_LAYERS; layer++ ) {
          LATM_LAYER_INFO *p_linfo = &(hAss->m_linfo[prog][layer]);

          if( p_linfo->streamID >= 0 ) {

            bitDemand+=4; /* streamID */
            switch( p_linfo->frameLengthType ) {
            case 0:
              streamDataLength -= bitDemand ;
              while( streamDataLength >= (255<<3) ) {
                bitDemand+=8;
                streamDataLength -= (255<<3);
              }

              bitDemand += 8;
              break;
              /*bitDemand += 1; endFlag
              break;*/

            case 1:
            case 4:
            case 6:

              break;

            default:
              return  0;
            }
            hAss->varStreamCnt++;
          }
        }
      }
      bitDemand+=4;
      //transportEnc_UpdateBitstreamField( hAss->hAssemble, streamCntPosition, hAss->varStreamCnt-1, 4 );
      //UINT pos = streamCntPosition-FDKgetValidBits(hAss->hAssemble);
      //FDKpushBack( hAss->hAssemble,  pos);
      //FDKwriteBits( hAss->hAssemble, hAss->varStreamCnt-1, 4);
      //FDKpushFor( hAss->hAssemble, pos-4);
    }
    break;

    default:
      return  0;
    }
  }

  return bitDemand ;
}

TRANSPORTENC_ERROR
CreateStreamMuxConfig(
                      HANDLE_LATM_STREAM hAss,
                      HANDLE_FDK_BITSTREAM hBs,
                      int bufferFullness,
                      CSTpCallBacks *cb
                     )
{
  INT streamIDcnt, tmp;
  int layer, prog;

  USHORT coreFrameOffset=0;

  hAss->audioMuxVersionA    = 0; /* for future extensions */
  hAss->streamMuxConfigBits = 0;

  FDKwriteBits( hBs, hAss->audioMuxVersion, 1 );                   /* audioMuxVersion */
  hAss->streamMuxConfigBits += 1;

  if ( hAss->audioMuxVersion == 1 ) {
    FDKwriteBits( hBs, hAss->audioMuxVersionA, 1 );                /* audioMuxVersionA */
    hAss->streamMuxConfigBits+=1;
  }

  if ( hAss->audioMuxVersionA == 0 )
  {
    if ( hAss->audioMuxVersion == 1 ) {
      hAss->streamMuxConfigBits+= transportEnc_LatmWriteValue( hBs, hAss->taraBufferFullness );/* taraBufferFullness */
    }
    FDKwriteBits( hBs, hAss->allStreamsSameTimeFraming ? 1:0, 1 ); /* allStreamsSameTimeFraming */
    FDKwriteBits( hBs, hAss->noSubframes-1, 6 );                   /* Number of Subframes */
    FDKwriteBits( hBs, hAss->noProgram-1, 4 );                     /* Number of Programs */

    hAss->streamMuxConfigBits+=11;

    streamIDcnt = 0;
    for( prog=0; prog<hAss->noProgram; prog++ ) {
      int transLayer = 0;

      FDKwriteBits( hBs, hAss->noLayer[prog]-1, 3 );
      hAss->streamMuxConfigBits+=3;

      for( layer=0; layer<LATM_MAX_LAYERS; layer++ ) {
        LATM_LAYER_INFO   *p_linfo = &(hAss->m_linfo[prog][layer]);
        CODER_CONFIG *p_lci   = hAss->config[prog][layer];

        p_linfo->streamID = -1;

        if( hAss->config[prog][layer] != NULL ) {
          int useSameConfig = 0;

          if( transLayer > 0 ) {
            FDKwriteBits( hBs, useSameConfig ? 1 : 0, 1 );
            hAss->streamMuxConfigBits+=1;
          }
          if( (useSameConfig == 0) || (transLayer==0) ) {
            UINT bits;

            if ( hAss->audioMuxVersion == 1 ) {
              FDKpushFor(hBs, 2); /* align to ASC, even if we do not know the length of the "ascLen" field yet */
            }

            bits = FDKgetValidBits( hBs );

            transportEnc_writeASC(
                    hBs,
                    hAss->config[prog][layer],
                    cb
                    );

            bits = FDKgetValidBits( hBs ) - bits;

            if ( hAss->audioMuxVersion == 1 ) {
              FDKpushBack(hBs, bits+2);
              hAss->streamMuxConfigBits += transportEnc_LatmWriteValue( hBs, bits );
              transportEnc_writeASC(
                      hBs,
                      hAss->config[prog][layer],
                      cb
                      );
            }

            hAss->streamMuxConfigBits += bits; /* add asc length to smc summary */
          }
          transLayer++;

          if( !hAss->allStreamsSameTimeFraming ) {
            if( streamIDcnt >= LATM_MAX_STREAM_ID )
              return TRANSPORTENC_INVALID_CONFIG;
          }
          p_linfo->streamID = streamIDcnt++;

          switch( p_lci->aot ) {
          case AOT_AAC_MAIN      :
          case AOT_AAC_LC        :
          case AOT_AAC_SSR       :
          case AOT_AAC_LTP       :
          case AOT_AAC_SCAL      :
          case AOT_ER_AAC_LD     :
          case AOT_ER_AAC_ELD    :
          case AOT_USAC:
          case AOT_RSVD50:
            p_linfo->frameLengthType = 0;

            FDKwriteBits( hBs, p_linfo->frameLengthType, 3 );                        /* frameLengthType */
            FDKwriteBits( hBs, bufferFullness, 8 );                           /* bufferFullness */
            hAss->streamMuxConfigBits+=11;

            if ( !hAss->allStreamsSameTimeFraming ) {
              CODER_CONFIG *p_lci_prev = hAss->config[prog][layer-1];
              if ( ((p_lci->aot == AOT_AAC_SCAL) || (p_lci->aot == AOT_ER_AAC_SCAL)) &&
                   ((p_lci_prev->aot == AOT_CELP) || (p_lci_prev->aot == AOT_ER_CELP)) ) {
                FDKwriteBits( hBs, coreFrameOffset, 6 );                      /* coreFrameOffset */
                hAss->streamMuxConfigBits+=6;
              }
            }
            break;

          case AOT_TWIN_VQ:
            p_linfo->frameLengthType = 1;
            tmp = ( (p_lci->bitsFrame+7) >> 3 ) - 20;                            /* transmission frame length in bytes */
            if( (tmp < 0) ) {
              return TRANSPORTENC_INVALID_TRANSMISSION_FRAME_LENGTH;
            }
            FDKwriteBits( hBs, p_linfo->frameLengthType, 3 );          /* frameLengthType */
            FDKwriteBits( hBs, tmp, 9 );
            hAss->streamMuxConfigBits+=12;

            p_linfo->frameLengthBits = (tmp+20) << 3;
            break;

          case AOT_CELP:
            p_linfo->frameLengthType = 4;
            FDKwriteBits( hBs, p_linfo->frameLengthType, 3 );          /* frameLengthType */
            hAss->streamMuxConfigBits+=3;
            {
              int i;
              for( i=0; i<62; i++ ) {
                if( celpFrameLengthTable[i] == p_lci->bitsFrame )
                  break;
              }
              if( i>=62 ) {
                return TRANSPORTENC_INVALID_CELP_FRAME_LENGTH;
              }

              FDKwriteBits( hBs, i, 6 );                                /* CELPframeLengthTabelIndex */
              hAss->streamMuxConfigBits+=6;
            }
            p_linfo->frameLengthBits = p_lci->bitsFrame;
            break;

          case AOT_HVXC:
            p_linfo->frameLengthType = 6;
            FDKwriteBits( hBs, p_linfo->frameLengthType, 3 );          /* frameLengthType */
            hAss->streamMuxConfigBits+=3;
            {
              int i;

              if( p_lci->bitsFrame == 40 ) {
                i = 0;
              } else if( p_lci->bitsFrame == 80 ) {
                i = 1;
              } else {
                return TRANSPORTENC_INVALID_FRAME_BITS;
              }
              FDKwriteBits( hBs, i, 1 );                                /* HVXCframeLengthTableIndex */
              hAss->streamMuxConfigBits+=1;
            }
            p_linfo->frameLengthBits = p_lci->bitsFrame;
            break;

          case AOT_NULL_OBJECT:
          default:
            return TRANSPORTENC_INVALID_AOT;
          }
        }
      }
    }

    FDKwriteBits( hBs, (hAss->otherDataLenBytes>0) ? 1:0, 1 );      /* otherDataPresent */
    hAss->streamMuxConfigBits+=1;

    if( hAss->otherDataLenBytes > 0 ) {

      INT otherDataLenTmp = hAss->otherDataLenBytes;
      INT escCnt = 0;
      INT otherDataLenEsc = 1;

      while(otherDataLenTmp) {
        otherDataLenTmp >>= 8;
        escCnt ++;
      }

      do {
        otherDataLenTmp = (hAss->otherDataLenBytes>>(escCnt*8)) & 0xFF;
        escCnt--;
        otherDataLenEsc = escCnt>0;

        FDKwriteBits( hBs, otherDataLenEsc, 1 );
        FDKwriteBits( hBs, otherDataLenTmp, 8 );
        hAss->streamMuxConfigBits+=9;
      } while(otherDataLenEsc);
    }

    {
      USHORT crcCheckPresent=0;
      USHORT crcCheckSum=0;

      FDKwriteBits( hBs, crcCheckPresent, 1 );               /* crcCheckPresent */
      hAss->streamMuxConfigBits+=1;
      if ( crcCheckPresent ){
        FDKwriteBits( hBs, crcCheckSum, 8 );                 /* crcCheckSum */
        hAss->streamMuxConfigBits+=8;
      }
    }

  } else {  /* if ( audioMuxVersionA == 0 ) */

    /* for future extensions */

  }

  return TRANSPORTENC_OK;
}


static TRANSPORTENC_ERROR
WriteAuPayloadLengthInfo( HANDLE_FDK_BITSTREAM hBitStream, int AuLengthBits )
{
  int restBytes;

  if( AuLengthBits % 8 )
    return TRANSPORTENC_INVALID_AU_LENGTH;

  while( AuLengthBits >= 255*8 ) {
    FDKwriteBits( hBitStream, 255, 8 );  /* 255 shows incomplete AU */
    AuLengthBits -= (255*8);
  }

  restBytes = (AuLengthBits) >> 3;
  FDKwriteBits( hBitStream, restBytes, 8 );

  return TRANSPORTENC_OK;
}

static
TRANSPORTENC_ERROR transportEnc_LatmSetNrOfSubframes( HANDLE_LATM_STREAM hAss,
                                                      INT noSubframes_next)    /* nr of access units / payloads within a latm frame */
{
  /* sanity chk */
  if (noSubframes_next < 1 || noSubframes_next > MAX_NR_OF_SUBFRAMES) {
    return TRANSPORTENC_LATM_INVALID_NR_OF_SUBFRAMES;
  }

  hAss->noSubframes_next = noSubframes_next;

  /* if at start then we can take over the value immediately, otherwise we have to wait for the next SMC */
  if ( (hAss->subFrameCnt == 0) && (hAss->latmFrameCounter == 0) ) {
    hAss->noSubframes = noSubframes_next;
  }

  return TRANSPORTENC_OK;
}

static
int allStreamsSameTimeFraming( HANDLE_LATM_STREAM hAss, UCHAR noProgram, UCHAR noLayer[] /* return */ )
{
  int prog, layer;

  signed int lastNoSamples   = -1;
  signed int minFrameSamples = FDK_INT_MAX;
  signed int maxFrameSamples = 0;

  signed int highestSamplingRate = -1;

  for( prog=0; prog<noProgram; prog++ ) {
    noLayer[prog] = 0;

    for( layer=0; layer<LATM_MAX_LAYERS; layer++ )
    {
      if( hAss->config[prog][layer] != NULL )
      {
        INT hsfSamplesFrame;

        noLayer[prog]++;

        if( highestSamplingRate < 0 )
          highestSamplingRate = hAss->config[prog][layer]->samplingRate;

        hsfSamplesFrame = hAss->config[prog][layer]->samplesPerFrame  * highestSamplingRate / hAss->config[prog][layer]->samplingRate;

        if( hsfSamplesFrame <= minFrameSamples ) minFrameSamples = hsfSamplesFrame;
        if( hsfSamplesFrame >= maxFrameSamples ) maxFrameSamples = hsfSamplesFrame;

        if( lastNoSamples == -1 ) {
          lastNoSamples                             = hsfSamplesFrame;
        } else {
          if( hsfSamplesFrame != lastNoSamples ) {
            return 0;
          }
        }
      }
    }
  }

  return 1;
}

/**
 * Initialize LATM/LOAS Stream and add layer 0 at program 0.
 */
static
TRANSPORTENC_ERROR transportEnc_InitLatmStream( HANDLE_LATM_STREAM hAss,
                                                int                fractDelayPresent,
                                                signed int         muxConfigPeriod, /* insert setup data every muxConfigPeriod frames */
                                                UINT               audioMuxVersion,
                                                TRANSPORT_TYPE     tt
                                              )
{
  TRANSPORTENC_ERROR ErrorStatus = TRANSPORTENC_OK;

  if (hAss == NULL)
    return TRANSPORTENC_INVALID_PARAMETER;

  hAss->tt = tt;

  hAss->noProgram = 1;

  hAss->audioMuxVersion = audioMuxVersion;

  /* Fill noLayer array using hAss->config */
  hAss->allStreamsSameTimeFraming = allStreamsSameTimeFraming( hAss, hAss->noProgram, hAss->noLayer );
  /* Only allStreamsSameTimeFraming==1 is supported */
  FDK_ASSERT(hAss->allStreamsSameTimeFraming);

  hAss->fractDelayPresent = fractDelayPresent;
  hAss->otherDataLenBytes = 0;

  hAss->varMode = LATMVAR_SIMPLE_SEQUENCE;

  /* initialize counters */
  hAss->subFrameCnt                  = 0;
  hAss->noSubframes                  = DEFAULT_LATM_NR_OF_SUBFRAMES;
  hAss->noSubframes_next             = DEFAULT_LATM_NR_OF_SUBFRAMES;

  /* sync layer related */
  hAss->audioMuxLengthBytes     = 0;

  hAss->latmFrameCounter        = 0;
  hAss->muxConfigPeriod = muxConfigPeriod;

  return ErrorStatus;
}


/**
 *
 */
UINT transportEnc_LatmCountTotalBitDemandHeader ( HANDLE_LATM_STREAM hAss , unsigned int streamDataLength )
{
  UINT bitDemand = 0;

  switch (hAss->tt) {
  case TT_MP4_LOAS:
  case TT_MP4_LATM_MCP0:
  case TT_MP4_LATM_MCP1:
    if (hAss->subFrameCnt == 0) {
      bitDemand  = transportEnc_LatmCountFixBitDemandHeader ( hAss );
    }
    bitDemand += transportEnc_LatmCountVarBitDemandHeader ( hAss , streamDataLength /*- bitDemand*/);
    break;
  default:
    break;
  }

  return bitDemand;
}

static TRANSPORTENC_ERROR
AdvanceAudioMuxElement (
        HANDLE_LATM_STREAM   hAss,
        HANDLE_FDK_BITSTREAM hBs,
        int                  auBits,
        int                  bufferFullness,
        CSTpCallBacks    *cb
        )
{
  TRANSPORTENC_ERROR ErrorStatus = TRANSPORTENC_OK;
  int insertMuxSetup;

  /* Insert setup data to assemble Buffer */
  if (hAss->subFrameCnt == 0)
  {
    if (hAss->muxConfigPeriod > 0) {
      insertMuxSetup = (hAss->latmFrameCounter == 0);
    } else  {
      insertMuxSetup = 0;
    }

    if (hAss->tt != TT_MP4_LATM_MCP0) {
      if( insertMuxSetup ) {
        FDKwriteBits( hBs, 0, 1 );  /* useSameStreamMux useNewStreamMux */
        CreateStreamMuxConfig(hAss, hBs, bufferFullness, cb);
        if (ErrorStatus != TRANSPORTENC_OK)
          return ErrorStatus;
      } else {
        FDKwriteBits( hBs, 1, 1 );   /* useSameStreamMux */
      }
    }
  }

  /* PayloadLengthInfo */
  {
    int prog, layer;

    for (prog = 0; prog < hAss->noProgram; prog++) {
      for (layer = 0; layer < hAss->noLayer[prog]; layer++) {
        ErrorStatus = WriteAuPayloadLengthInfo( hBs, auBits );
        if (ErrorStatus != TRANSPORTENC_OK)
          return ErrorStatus;
      }
    }
  }
  /* At this point comes the access unit. */

  return TRANSPORTENC_OK;
}

TRANSPORTENC_ERROR
transportEnc_LatmWrite (
        HANDLE_LATM_STREAM    hAss,
        HANDLE_FDK_BITSTREAM  hBs,
        int                   auBits,
        int                   bufferFullness,
        CSTpCallBacks     *cb
        )
{
  TRANSPORTENC_ERROR ErrorStatus;

  if (hAss->subFrameCnt == 0) {
    /* Start new frame */
    FDKresetBitbuffer(hBs, BS_WRITER);
  }

  hAss->latmSubframeStart = FDKgetValidBits(hBs);

  /* Insert syncword and syncword distance
     - only if loas
     - we must update the syncword distance (=audiomuxlengthbytes) later
   */
  if( hAss->tt == TT_MP4_LOAS && hAss->subFrameCnt == 0)
  {
    /* Start new LOAS frame */
    FDKwriteBits( hBs, 0x2B7, 11 );
    hAss->audioMuxLengthBytes = 0;
    hAss->audioMuxLengthBytesPos = FDKgetValidBits( hBs );  /* store read pointer position */
    FDKwriteBits( hBs, hAss->audioMuxLengthBytes, 13 );
  }

  ErrorStatus = AdvanceAudioMuxElement(
          hAss,
          hBs,
          auBits,
          bufferFullness,
          cb
          );

  if (ErrorStatus != TRANSPORTENC_OK)
    return ErrorStatus;

  return ErrorStatus;
}

void transportEnc_LatmAdjustSubframeBits(HANDLE_LATM_STREAM    hAss,
                                         int                  *bits)
{
  /* Substract bits from possible previous subframe */
  *bits -= hAss->latmSubframeStart;
  /* Add fill bits */
  if (hAss->subFrameCnt == 0)
    *bits += hAss->fillBits;
}


void transportEnc_LatmGetFrame(HANDLE_LATM_STREAM    hAss,
                               HANDLE_FDK_BITSTREAM  hBs,
                               int                  *bytes)
{

  hAss->subFrameCnt++;
  if (hAss->subFrameCnt >= hAss->noSubframes)
  {

    /* Add LOAS frame length if required. */
    if (hAss->tt == TT_MP4_LOAS)
    {
      int latmBytes;

      latmBytes = (FDKgetValidBits(hBs)+7) >> 3;

      /* write length info into assembler buffer */
      hAss->audioMuxLengthBytes = latmBytes - 3; /* 3=Syncword + length */
      {
        FDK_BITSTREAM tmpBuf;

        FDKinitBitStream( &tmpBuf, hBs->hBitBuf.Buffer, hBs->hBitBuf.bufSize, 0, BS_WRITER ) ;
        FDKpushFor( &tmpBuf, hAss->audioMuxLengthBytesPos );
        FDKwriteBits( &tmpBuf, hAss->audioMuxLengthBytes, 13 );
        FDKsyncCache( &tmpBuf );
      }
    }

    /* Write AudioMuxElement byte alignment fill bits */
    FDKwriteBits(hBs, 0, hAss->fillBits);

    FDK_ASSERT( (FDKgetValidBits(hBs) % 8) == 0);

    hAss->subFrameCnt = 0;

    FDKsyncCache(hBs);
    *bytes = (FDKgetValidBits(hBs) + 7)>>3;
    //FDKfetchBuffer(hBs, buffer, (UINT*)bytes);

    if (hAss->muxConfigPeriod > 0)
    {
      hAss->latmFrameCounter++;

      if (hAss->latmFrameCounter >= hAss->muxConfigPeriod) {
        hAss->latmFrameCounter = 0;
        hAss->noSubframes = hAss->noSubframes_next;
      }
    }
  } else {
    /* No data this time */
    *bytes = 0;
  }
}

/**
 * Init LATM/LOAS
 */
TRANSPORTENC_ERROR transportEnc_Latm_Init(
        HANDLE_LATM_STREAM  hAss,
        HANDLE_FDK_BITSTREAM hBs,
        CODER_CONFIG  *layerConfig,
        UINT audioMuxVersion,
        TRANSPORT_TYPE tt,
        CSTpCallBacks *cb
        )
{
  TRANSPORTENC_ERROR ErrorStatus;
  int fractDelayPresent = 0;
  int prog, layer;

  int setupDataDistanceFrames = layerConfig->headerPeriod;

  FDK_ASSERT(setupDataDistanceFrames>=0);

  for (prog=0; prog<LATM_MAX_PROGRAMS; prog++) {
    for (layer=0; layer<LATM_MAX_LAYERS; layer++) {
      hAss->config[prog][layer] = NULL;
      hAss->m_linfo[prog][layer].streamID = -1;
    }
  }

  hAss->config[0][0] = layerConfig;
  hAss->m_linfo[0][0].streamID = 0;

  ErrorStatus = transportEnc_InitLatmStream( hAss,
                                             fractDelayPresent,
                                             setupDataDistanceFrames,
                                             (audioMuxVersion)?1:0,
                                             tt
                                             );
  if (ErrorStatus != TRANSPORTENC_OK)
    goto bail;

  ErrorStatus = transportEnc_LatmSetNrOfSubframes(
                                                   hAss,
                                                   layerConfig->nSubFrames
                                                  );
  if (ErrorStatus != TRANSPORTENC_OK)
    goto bail;

  /* Get the size of the StreamMuxConfig somehow */
  AdvanceAudioMuxElement(hAss, hBs, 0, 0, cb);
  //CreateStreamMuxConfig(hAss, hBs, 0);

bail:
  return ErrorStatus;
}