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

© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
  All rights reserved.

 1.    INTRODUCTION
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
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.

AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
of the MPEG specifications.

Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
individually for the purpose of encoding or decoding bit streams in products that are compliant with
the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
software may already be covered under those patent licenses when it is used for those licensed purposes only.

Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
applications information and documentation.

2.    COPYRIGHT LICENSE

Redistribution and use in source and binary forms, with or without modification, are permitted without
payment of copyright license fees provided that you satisfy the following conditions:

You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
your modifications thereto in source code form.

You must retain the complete text of this software license in the documentation and/or other materials
provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
modifications thereto to recipients of copies in binary form.

The name of Fraunhofer may not be used to endorse or promote products derived from this library without
prior written permission.

You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
software or your modifications thereto.

Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
and the date of any change. For modified versions of the FDK AAC Codec, the term
"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."

3.    NO PATENT LICENSE

NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
respect to this software.

You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
by appropriate patent licenses.

4.    DISCLAIMER

This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
or business interruption, however caused and on any theory of liability, whether in contract, strict
liability, or tort (including negligence), arising in any way out of the use of this software, even if
advised of the possibility of such damage.

5.    CONTACT INFORMATION

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 Audio Encoder **************************

   Initial author:       M.Werner
   contents/description: Noiseless coder module

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

#include "dyn_bits.h"
#include "bit_cnt.h"
#include "psy_const.h"
#include "aacenc_pns.h"
#include "aacEnc_ram.h"
#include "aacEnc_rom.h"

typedef INT (*lookUpTable)[CODE_BOOK_ESC_NDX + 1];

static INT FDKaacEnc_getSideInfoBits(
        const SECTION_INFO* const huffsection,
        const SHORT* const        sideInfoTab,
        const INT                 useHCR
        )
{
  INT sideInfoBits;

  if ( useHCR && ((huffsection->codeBook == 11) || (huffsection->codeBook >= 16)) ) {
    sideInfoBits = 5;
  }
  else {
    sideInfoBits = sideInfoTab[huffsection->sfbCnt];
  }

  return (sideInfoBits);
}

/* count bits using all possible tables */
static void FDKaacEnc_buildBitLookUp(
        const SHORT* const        quantSpectrum,
        const INT                 maxSfb,
        const INT* const          sfbOffset,
        const UINT* const         sfbMax,
        INT                       bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        SECTION_INFO* const       huffsection
        )
{
  INT i, sfbWidth;

  for (i = 0; i < maxSfb; i++)
  {
    huffsection[i].sfbCnt = 1;
    huffsection[i].sfbStart = i;
    huffsection[i].sectionBits = INVALID_BITCOUNT;
    huffsection[i].codeBook = -1;
    sfbWidth = sfbOffset[i + 1] - sfbOffset[i];
    FDKaacEnc_bitCount(quantSpectrum + sfbOffset[i], sfbWidth, sfbMax[i], bitLookUp[i]);
  }
}

/* essential helper functions */
static INT FDKaacEnc_findBestBook(
        const INT* const          bc,
        INT* const                book,
        const INT                 useVCB11
        )
{
  INT minBits = INVALID_BITCOUNT, j;

  int end = CODE_BOOK_ESC_NDX;


  for (j = 0; j <= end; j++)
  {
    if (bc[j] < minBits)
    {
      minBits = bc[j];
      *book = j;
    }
  }
  return (minBits);
}

static INT FDKaacEnc_findMinMergeBits(
        const INT* const          bc1,
        const INT* const          bc2,
        const INT                 useVCB11
        )
{
  INT minBits = INVALID_BITCOUNT, j;

  int end = CODE_BOOK_ESC_NDX;


  for (j = 0; j <= end; j++)
  {
    if (bc1[j] + bc2[j] < minBits)
    {
      minBits = bc1[j] + bc2[j];
    }
  }
  return (minBits);
}

static void FDKaacEnc_mergeBitLookUp(
        INT* const                bc1,
        const INT* const          bc2
        )
{
  int j;

  for (j = 0; j <= CODE_BOOK_ESC_NDX; j++)
  {
    bc1[j] = fixMin(bc1[j] + bc2[j], INVALID_BITCOUNT);
  }
}

static INT FDKaacEnc_findMaxMerge(
        const INT* const          mergeGainLookUp,
        const SECTION_INFO* const  huffsection,
        const INT maxSfb,
        INT* const                maxNdx
        )
{
  INT i, maxMergeGain = 0;

  for (i = 0; i + huffsection[i].sfbCnt < maxSfb; i += huffsection[i].sfbCnt)
  {
    if (mergeGainLookUp[i] > maxMergeGain)
    {
      maxMergeGain = mergeGainLookUp[i];
      *maxNdx = i;
    }
  }
  return (maxMergeGain);
}

static INT FDKaacEnc_CalcMergeGain(
        const SECTION_INFO* const huffsection,
        const INT                 bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        const SHORT* const        sideInfoTab,
        const INT                 ndx1,
        const INT                 ndx2,
        const INT                 useVCB11
        )
{
  INT MergeGain, MergeBits, SplitBits;

  MergeBits = sideInfoTab[huffsection[ndx1].sfbCnt + huffsection[ndx2].sfbCnt] + FDKaacEnc_findMinMergeBits(bitLookUp[ndx1], bitLookUp[ndx2], useVCB11);
  SplitBits = huffsection[ndx1].sectionBits + huffsection[ndx2].sectionBits; /* Bit amount for splitted huffsections */
  MergeGain = SplitBits - MergeBits;

  if ( (huffsection[ndx1].codeBook==CODE_BOOK_PNS_NO)||(huffsection[ndx2].codeBook==CODE_BOOK_PNS_NO)
    || (huffsection[ndx1].codeBook==CODE_BOOK_IS_OUT_OF_PHASE_NO)||(huffsection[ndx2].codeBook==CODE_BOOK_IS_OUT_OF_PHASE_NO)
    || (huffsection[ndx1].codeBook==CODE_BOOK_IS_IN_PHASE_NO)||(huffsection[ndx2].codeBook==CODE_BOOK_IS_IN_PHASE_NO)
    )
  {
    MergeGain = -1;
  }

  return (MergeGain);
}


/* sectioning Stage 0:find minimum codbooks */
static void FDKaacEnc_gmStage0(
        SECTION_INFO* const RESTRICT huffsection,
        const INT                    bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        const INT                    maxSfb,
        const INT* const             noiseNrg,
        const INT* const             isBook
        )
{
  INT i;

  for (i = 0; i < maxSfb; i++)
  {
    /* Side-Info bits will be calculated in Stage 1! */
    if (huffsection[i].sectionBits == INVALID_BITCOUNT)
    {
      /* intensity and pns codebooks are already allocated in bitcount.c */
      if(noiseNrg[i] != NO_NOISE_PNS){
        huffsection[i].codeBook=CODE_BOOK_PNS_NO;
        huffsection[i].sectionBits = 0;
      }
      else if( isBook[i] ) {
        huffsection[i].codeBook=isBook[i];
        huffsection[i].sectionBits = 0;
      }
      else {
        huffsection[i].sectionBits = FDKaacEnc_findBestBook(bitLookUp[i], &(huffsection[i].codeBook), 0); /* useVCB11 must be 0!!! */
      }
    }
  }
}

/*
   sectioning Stage 1:merge all connected regions with the same code book and
   calculate side info
 */
static void FDKaacEnc_gmStage1(
        SECTION_INFO* const RESTRICT huffsection,
        INT                          bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        const INT                    maxSfb,
        const SHORT* const           sideInfoTab,
        const INT                    useVCB11
        )
{
  INT mergeStart = 0, mergeEnd;

  do
  {
    for (mergeEnd = mergeStart + 1; mergeEnd < maxSfb; mergeEnd++)
    {
      if (huffsection[mergeStart].codeBook != huffsection[mergeEnd].codeBook)
        break;


      /* we can merge. update tables, side info bits will be updated outside of this loop */
      huffsection[mergeStart].sfbCnt++;
      huffsection[mergeStart].sectionBits += huffsection[mergeEnd].sectionBits;

      /* update bit look up for all code books */
      FDKaacEnc_mergeBitLookUp(bitLookUp[mergeStart], bitLookUp[mergeEnd]);
    }

    /* add side info info bits */
    huffsection[mergeStart].sectionBits += FDKaacEnc_getSideInfoBits(&huffsection[mergeStart], sideInfoTab, useVCB11);
    huffsection[mergeEnd - 1].sfbStart = huffsection[mergeStart].sfbStart;      /* speed up prev search */

    mergeStart = mergeEnd;

  } while (mergeStart < maxSfb);
}

/*
   sectioning Stage 2:greedy merge algorithm, merge connected sections with
   maximum bit gain until no more gain is possible
 */
static void
FDKaacEnc_gmStage2(
        SECTION_INFO* const RESTRICT huffsection,
        INT* const RESTRICT          mergeGainLookUp,
        INT                          bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        const INT                    maxSfb,
        const SHORT* const           sideInfoTab,
        const INT                    useVCB11
        )
{
  INT i;

  for (i = 0; i + huffsection[i].sfbCnt < maxSfb; i += huffsection[i].sfbCnt)
  {
    mergeGainLookUp[i] = FDKaacEnc_CalcMergeGain(huffsection,
                                       bitLookUp,
                                       sideInfoTab,
                                       i,
                                       i + huffsection[i].sfbCnt,
                                       useVCB11);
  }

  while (TRUE)
  {
    INT maxMergeGain, maxNdx = 0, maxNdxNext, maxNdxLast;

    maxMergeGain = FDKaacEnc_findMaxMerge(mergeGainLookUp, huffsection, maxSfb, &maxNdx);

    /* exit while loop if no more gain is possible */
    if (maxMergeGain <= 0)
      break;

    maxNdxNext = maxNdx + huffsection[maxNdx].sfbCnt;

    /* merge sections with maximum bit gain */
    huffsection[maxNdx].sfbCnt += huffsection[maxNdxNext].sfbCnt;
    huffsection[maxNdx].sectionBits += huffsection[maxNdxNext].sectionBits - maxMergeGain;

    /* update bit look up table for merged huffsection  */
    FDKaacEnc_mergeBitLookUp(bitLookUp[maxNdx], bitLookUp[maxNdxNext]);

    /* update mergeLookUpTable */
    if (maxNdx != 0)
    {
      maxNdxLast = huffsection[maxNdx - 1].sfbStart;
      mergeGainLookUp[maxNdxLast] = FDKaacEnc_CalcMergeGain(huffsection,
                                                  bitLookUp,
                                                  sideInfoTab,
                                                  maxNdxLast,
                                                  maxNdx,
                                                  useVCB11);

    }
    maxNdxNext = maxNdx + huffsection[maxNdx].sfbCnt;

    huffsection[maxNdxNext - 1].sfbStart = huffsection[maxNdx].sfbStart;

    if (maxNdxNext < maxSfb)
      mergeGainLookUp[maxNdx] = FDKaacEnc_CalcMergeGain(huffsection,
                                              bitLookUp,
                                              sideInfoTab,
                                              maxNdx,
                                              maxNdxNext,
                                              useVCB11);

  }
}

/* count bits used by the noiseless coder */
static void FDKaacEnc_noiselessCounter(
        SECTION_DATA* const RESTRICT sectionData,
        INT                          mergeGainLookUp[MAX_SFB_LONG],
        INT                          bitLookUp[MAX_SFB_LONG][CODE_BOOK_ESC_NDX + 1],
        const SHORT* const           quantSpectrum,
        const UINT* const            maxValueInSfb,
        const INT* const             sfbOffset,
        const INT                    blockType,
        const INT* const             noiseNrg,
        const INT* const             isBook,
        const INT                    useVCB11
        )
{
  INT grpNdx, i;
  const SHORT *sideInfoTab = NULL;
  SECTION_INFO *huffsection;

  /* use appropriate side info table */
  switch (blockType)
  {
  case LONG_WINDOW:
  case START_WINDOW:
  case STOP_WINDOW:
    sideInfoTab = FDKaacEnc_sideInfoTabLong;
    break;
  case SHORT_WINDOW:
    sideInfoTab = FDKaacEnc_sideInfoTabShort;
    break;
  }

  sectionData->noOfSections = 0;
  sectionData->huffmanBits = 0;
  sectionData->sideInfoBits = 0;


  if (sectionData->maxSfbPerGroup == 0)
    return;

  /* loop trough groups */
  for (grpNdx = 0; grpNdx < sectionData->sfbCnt; grpNdx += sectionData->sfbPerGroup)
  {
    huffsection = sectionData->huffsection + sectionData->noOfSections;

    /* count bits in this group */
    FDKaacEnc_buildBitLookUp(quantSpectrum,
                   sectionData->maxSfbPerGroup,
                   sfbOffset + grpNdx,
                   maxValueInSfb + grpNdx,
                   bitLookUp,
                   huffsection);

    /* 0.Stage :Find minimum Codebooks */
    FDKaacEnc_gmStage0(huffsection, bitLookUp, sectionData->maxSfbPerGroup, noiseNrg+grpNdx, isBook+grpNdx);

    /* 1.Stage :Merge all connected regions with the same code book */
    FDKaacEnc_gmStage1(huffsection, bitLookUp, sectionData->maxSfbPerGroup, sideInfoTab, useVCB11);


    /*
       2.Stage
       greedy merge algorithm, merge connected huffsections with maximum bit
       gain until no more gain is possible
     */

    FDKaacEnc_gmStage2(huffsection,
             mergeGainLookUp,
             bitLookUp,
             sectionData->maxSfbPerGroup,
             sideInfoTab,
             useVCB11);



    /*
       compress output, calculate total huff and side bits
       since we did not update the actual codebook in stage 2
       to save time, we must set it here for later use in bitenc
     */

    for (i = 0; i < sectionData->maxSfbPerGroup; i += huffsection[i].sfbCnt)
    {
      if ((huffsection[i].codeBook==CODE_BOOK_PNS_NO) ||
          (huffsection[i].codeBook==CODE_BOOK_IS_OUT_OF_PHASE_NO) ||
          (huffsection[i].codeBook==CODE_BOOK_IS_IN_PHASE_NO))
      {
        huffsection[i].sectionBits=0;
      } else {
        /* the sections in the sectionData are now marked with the optimal code book */

          FDKaacEnc_findBestBook(bitLookUp[i], &(huffsection[i].codeBook), useVCB11);

        sectionData->huffmanBits += huffsection[i].sectionBits - FDKaacEnc_getSideInfoBits(&huffsection[i], sideInfoTab, useVCB11);
      }

      huffsection[i].sfbStart += grpNdx;

      /* sum up side info bits (section data bits) */
      sectionData->sideInfoBits += FDKaacEnc_getSideInfoBits(&huffsection[i], sideInfoTab, useVCB11);
      sectionData->huffsection[sectionData->noOfSections++] = huffsection[i];
    }
  }
}


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

     functionname: FDKaacEnc_scfCount
     returns     : ---
     description : count bits used by scalefactors.

                   not in all cases if maxValueInSfb[] == 0 we set deltaScf
                   to zero. only if the difference of the last and future
                   scalefacGain is not greater then CODE_BOOK_SCF_LAV (60).

     example:
                  ^
     scalefacGain |
                  |
                  |       last 75
                  |          |
                  |          |
                  |          |
                  |          |      current 50
                  |          |          |
                  |          |          |
                  |          |          |
                  |          |          |
                  |          |          |      future 5
                  |          |          |          |
                  --- ... ---------------------------- ... --------->
                                                                sfb


                  if maxValueInSfb[] of current is zero because of a
                  notfallstrategie, we do not save bits and transmit a
                  deltaScf of 25. otherwise the deltaScf between the last
                  scalfacGain (75) and the future scalefacGain (5) is 70.

********************************************************************************/
static void FDKaacEnc_scfCount(
        const INT* const             scalefacGain,
        const UINT* const            maxValueInSfb,
        SECTION_DATA* const RESTRICT sectionData,
        const INT* const             isScale
        )
{
  INT i, j, k, m, n;

  INT lastValScf     = 0;
  INT deltaScf       = 0;
  INT found          = 0;
  INT scfSkipCounter = 0;
  INT lastValIs      = 0;

  sectionData->scalefacBits = 0;

  if (scalefacGain == NULL)
    return;

  sectionData->firstScf = 0;

  for (i=0; i<sectionData->noOfSections; i++)
  {
    if (sectionData->huffsection[i].codeBook != CODE_BOOK_ZERO_NO)
    {
      sectionData->firstScf = sectionData->huffsection[i].sfbStart;
      lastValScf = scalefacGain[sectionData->firstScf];
      break;
    }
  }

  for (i=0; i<sectionData->noOfSections; i++)
  {
    if ((sectionData->huffsection[i].codeBook == CODE_BOOK_IS_OUT_OF_PHASE_NO) ||
        (sectionData->huffsection[i].codeBook == CODE_BOOK_IS_IN_PHASE_NO))
    {
      for (j = sectionData->huffsection[i].sfbStart;
           j < sectionData->huffsection[i].sfbStart + sectionData->huffsection[i].sfbCnt;
           j++)
      {
        INT deltaIs = isScale[j]-lastValIs;
        lastValIs   = isScale[j];
        sectionData->scalefacBits+=FDKaacEnc_bitCountScalefactorDelta(deltaIs);
      }
    } /* Intensity */
    else if ((sectionData->huffsection[i].codeBook != CODE_BOOK_ZERO_NO) &&
             (sectionData->huffsection[i].codeBook != CODE_BOOK_PNS_NO))
    {
      INT tmp = sectionData->huffsection[i].sfbStart + sectionData->huffsection[i].sfbCnt;
      for (j = sectionData->huffsection[i].sfbStart; j<tmp; j++)
      {
        /* check if we can repeat the last value to save bits */
        if (maxValueInSfb[j] == 0)
        {
          found = 0;
          /* are scalefactors skipped? */
          if (scfSkipCounter == 0)
          {
            /* end of section */
            if (j == (tmp - 1) )
              found = 0;  /* search in other sections for maxValueInSfb != 0 */
            else
            {
              /* search in this section for the next maxValueInSfb[] != 0 */
              for (k = (j+1); k < tmp; k++)
              {
                if (maxValueInSfb[k] != 0)
                {
                  found = 1;
                  if ( (fixp_abs(scalefacGain[k] - lastValScf)) <= CODE_BOOK_SCF_LAV)
                     deltaScf = 0; /* save bits */
                  else
                  {
                    /* do not save bits */
                    deltaScf = lastValScf - scalefacGain[j];
                    lastValScf = scalefacGain[j];
                    scfSkipCounter = 0;
                  }
                  break;
                }
                /* count scalefactor skip */
                scfSkipCounter++;
              }
            }

            /* search for the next maxValueInSfb[] != 0 in all other sections */
            for (m=(i+1); (m < sectionData->noOfSections) && (found == 0); m++)
            {
              if ((sectionData->huffsection[m].codeBook != CODE_BOOK_ZERO_NO) && (sectionData->huffsection[m].codeBook != CODE_BOOK_PNS_NO))
              {
                INT end = sectionData->huffsection[m].sfbStart + sectionData->huffsection[m].sfbCnt;
                for (n = sectionData->huffsection[m].sfbStart; n<end; n++)
                {
                  if (maxValueInSfb[n] != 0)
                  {
                    found = 1;
                    if (fixp_abs(scalefacGain[n] - lastValScf) <= CODE_BOOK_SCF_LAV)
                      deltaScf = 0;  /* save bits */
                    else
                    {
                      /* do not save bits */
                      deltaScf = lastValScf - scalefacGain[j];
                      lastValScf = scalefacGain[j];
                      scfSkipCounter = 0;
                    }
                    break;
                  }
                  /* count scalefactor skip */
                  scfSkipCounter++;
                }
              }
            }
            /* no maxValueInSfb[] != 0 found */
            if (found == 0)
            {
              deltaScf = 0;
              scfSkipCounter = 0;
            }
          }
          else {
            /* consider skipped scalefactors */
            deltaScf = 0;
            scfSkipCounter--;
          }
        }
        else {
          deltaScf = lastValScf - scalefacGain[j];
          lastValScf = scalefacGain[j];
        }
        sectionData->scalefacBits += FDKaacEnc_bitCountScalefactorDelta(deltaScf);
      }
    }
  } /* for (i=0; i<sectionData->noOfSections; i++) */
}

#ifdef PNS_PRECOUNT_ENABLE
/*
  preCount bits used pns
*/
/* estimate bits used by pns for correction of static bits */
/* no codebook switch estimation, see AAC LD FASTENC */
INT noisePreCount(const INT *noiseNrg, INT maxSfb)
{
  INT   noisePCMFlag = TRUE;
  INT   lastValPns = 0, deltaPns;
  int   i, bits=0;

 for (i = 0; i < maxSfb; i++) {
   if (noiseNrg[i] != NO_NOISE_PNS) {

     if (noisePCMFlag) {
       bits+=PNS_PCM_BITS;
       lastValPns   = noiseNrg[i];
       noisePCMFlag = FALSE;
     }else {
       deltaPns     = noiseNrg[i]-lastValPns;
       lastValPns   = noiseNrg[i];
       bits+=FDKaacEnc_bitCountScalefactorDelta(deltaPns);
     }
   }
 }
 return ( bits );
}
#endif /* PNS_PRECOUNT_ENABLE */

/* count bits used by pns */
static void FDKaacEnc_noiseCount(
        SECTION_DATA* const RESTRICT sectionData,
        const INT* const             noiseNrg
        )
{
  INT noisePCMFlag = TRUE;
  INT lastValPns = 0, deltaPns;
  int i, j;

  sectionData->noiseNrgBits = 0;

  for (i = 0; i < sectionData->noOfSections; i++) {
    if (sectionData->huffsection[i].codeBook == CODE_BOOK_PNS_NO) {
      int sfbStart = sectionData->huffsection[i].sfbStart;
      int sfbEnd = sfbStart + sectionData->huffsection[i].sfbCnt;
      for (j=sfbStart; j<sfbEnd; j++) {

        if (noisePCMFlag) {
          sectionData->noiseNrgBits+=PNS_PCM_BITS;
          lastValPns   = noiseNrg[j];
          noisePCMFlag = FALSE;
        } else {
          deltaPns     = noiseNrg[j]-lastValPns;
          lastValPns   = noiseNrg[j];
          sectionData->noiseNrgBits+=FDKaacEnc_bitCountScalefactorDelta(deltaPns);
        }
      }
    }
  }
}

INT FDKaacEnc_dynBitCount(
        BITCNTR_STATE* const         hBC,
        const SHORT* const           quantSpectrum,
        const UINT* const            maxValueInSfb,
        const INT* const             scalefac,
        const INT                    blockType,
        const INT                    sfbCnt,
        const INT                    maxSfbPerGroup,
        const INT                    sfbPerGroup,
        const INT* const             sfbOffset,
        SECTION_DATA* const RESTRICT sectionData,
        const INT* const             noiseNrg,
        const INT* const             isBook,
        const INT* const             isScale,
        const UINT                   syntaxFlags
        )
{
  sectionData->blockType      = blockType;
  sectionData->sfbCnt         = sfbCnt;
  sectionData->sfbPerGroup    = sfbPerGroup;
  sectionData->noOfGroups     = sfbCnt / sfbPerGroup;
  sectionData->maxSfbPerGroup = maxSfbPerGroup;

  FDKaacEnc_noiselessCounter(
                   sectionData,
                   hBC->mergeGainLookUp,
                   (lookUpTable)hBC->bitLookUp,
                   quantSpectrum,
                   maxValueInSfb,
                   sfbOffset,
                   blockType,
                   noiseNrg,
                   isBook,
                   (syntaxFlags & AC_ER_VCB11)?1:0);

  FDKaacEnc_scfCount(
           scalefac,
           maxValueInSfb,
           sectionData,
           isScale);

  FDKaacEnc_noiseCount(sectionData,
             noiseNrg);

  return (sectionData->huffmanBits +
          sectionData->sideInfoBits +
          sectionData->scalefacBits +
          sectionData->noiseNrgBits);
}

INT FDKaacEnc_BCNew(BITCNTR_STATE **phBC
         ,UCHAR* dynamic_RAM
         )
{
  BITCNTR_STATE *hBC =  GetRam_aacEnc_BitCntrState();

  if (hBC)
  {
    *phBC = hBC;
    hBC->bitLookUp       = GetRam_aacEnc_BitLookUp(0,dynamic_RAM);
    hBC->mergeGainLookUp = GetRam_aacEnc_MergeGainLookUp(0,dynamic_RAM);
    if (hBC->bitLookUp       == 0 ||
        hBC->mergeGainLookUp == 0)
    {
      return 1;
    }
  }
  return (hBC == 0) ? 1 : 0;
}

void FDKaacEnc_BCClose(BITCNTR_STATE **phBC)
{
  if (*phBC!=NULL) {

    FreeRam_aacEnc_BitCntrState(phBC);
  }
}