tpenc_latm.cpp - Android社区 - https://www.androidos.net.cn/

/* -----------------------------------------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

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the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
This FDK AAC Codec software is intended to be used on a wide variety of Android devices.

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Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
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Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
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Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany

www.iis.fraunhofer.de/amm
amm-info@iis.fraunhofer.de
----------------------------------------------------------------------------------------------------------- */

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

Author(s):
   Description:

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

#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->taraBufferFullness  = 0xFF;
  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) ) {
            const UINT alignAnchor = FDKgetValidBits(hBs);

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

if ( hAss->audioMuxVersion == 1 ) {
              UINT ascLen = transportEnc_LatmWriteValue(hBs, 0);
              FDKbyteAlign(hBs, alignAnchor);
              ascLen = FDKgetValidBits(hBs) - alignAnchor - ascLen;
              FDKpushBack(hBs, FDKgetValidBits(hBs) - alignAnchor);

transportEnc_LatmWriteValue(hBs, ascLen);

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

FDKbyteAlign(hBs, alignAnchor); /* asc length fillbits */
            }

hAss->streamMuxConfigBits += FDKgetValidBits(hBs) - alignAnchor; /* 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:
            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;
}

C++程序 | 882行 | 26.81 KB

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