path: root/libSBRenc/src/ps_encode.cpp

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

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----------------------------------------------------------------------------- */

/**************************** SBR encoder library ******************************

   Author(s):   M. Neuendorf, N. Rettelbach, M. Multrus

   Description: PS parameter extraction, encoding

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

/*!
  \file
  \brief  PS parameter extraction, encoding functions $Revision: 96441 $
*/

#include "ps_main.h"
#include "ps_encode.h"
#include "qmf.h"
#include "sbr_misc.h"
#include "sbrenc_ram.h"

#include "genericStds.h"

inline void FDKsbrEnc_addFIXP_DBL(const FIXP_DBL *X, const FIXP_DBL *Y,
                                  FIXP_DBL *Z, INT n) {
  for (INT i = 0; i < n; i++) Z[i] = (X[i] >> 1) + (Y[i] >> 1);
}

#define LOG10_2_10 3.01029995664f /* 10.0f*log10(2.f) */

static const INT
    iidGroupBordersLoRes[QMF_GROUPS_LO_RES + SUBQMF_GROUPS_LO_RES + 1] = {
        0,  1,  2,  3,  4,  5, /* 6 subqmf subbands - 0th qmf subband */
        6,  7,                 /* 2 subqmf subbands - 1st qmf subband */
        8,  9,                 /* 2 subqmf subbands - 2nd qmf subband */
        10, 11, 12, 13, 14, 15, 16, 18, 21, 25, 30, 42, 71};

static const UCHAR
    iidGroupWidthLdLoRes[QMF_GROUPS_LO_RES + SUBQMF_GROUPS_LO_RES] = {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 3, 4, 5};

static const INT subband2parameter20[QMF_GROUPS_LO_RES + SUBQMF_GROUPS_LO_RES] =
    {1, 0, 0,  1,  2,  3, /* 6 subqmf subbands - 0th qmf subband */
     4, 5,                /* 2 subqmf subbands - 1st qmf subband */
     6, 7,                /* 2 subqmf subbands - 2nd qmf subband */
     8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19};

typedef enum {
  MAX_TIME_DIFF_FRAMES = 20,
  MAX_PS_NOHEADER_CNT = 10,
  MAX_NOENV_CNT = 10,
  DO_NOT_USE_THIS_MODE = 0x7FFFFF
} __PS_CONSTANTS;

static const FIXP_DBL iidQuant_fx[15] = {
    (FIXP_DBL)0xce000000, (FIXP_DBL)0xdc000000, (FIXP_DBL)0xe4000000,
    (FIXP_DBL)0xec000000, (FIXP_DBL)0xf2000000, (FIXP_DBL)0xf8000000,
    (FIXP_DBL)0xfc000000, (FIXP_DBL)0x00000000, (FIXP_DBL)0x04000000,
    (FIXP_DBL)0x08000000, (FIXP_DBL)0x0e000000, (FIXP_DBL)0x14000000,
    (FIXP_DBL)0x1c000000, (FIXP_DBL)0x24000000, (FIXP_DBL)0x32000000};

static const FIXP_DBL iidQuantFine_fx[31] = {
    (FIXP_DBL)0x9c000001, (FIXP_DBL)0xa6000001, (FIXP_DBL)0xb0000001,
    (FIXP_DBL)0xba000001, (FIXP_DBL)0xc4000000, (FIXP_DBL)0xce000000,
    (FIXP_DBL)0xd4000000, (FIXP_DBL)0xda000000, (FIXP_DBL)0xe0000000,
    (FIXP_DBL)0xe6000000, (FIXP_DBL)0xec000000, (FIXP_DBL)0xf0000000,
    (FIXP_DBL)0xf4000000, (FIXP_DBL)0xf8000000, (FIXP_DBL)0xfc000000,
    (FIXP_DBL)0x00000000, (FIXP_DBL)0x04000000, (FIXP_DBL)0x08000000,
    (FIXP_DBL)0x0c000000, (FIXP_DBL)0x10000000, (FIXP_DBL)0x14000000,
    (FIXP_DBL)0x1a000000, (FIXP_DBL)0x20000000, (FIXP_DBL)0x26000000,
    (FIXP_DBL)0x2c000000, (FIXP_DBL)0x32000000, (FIXP_DBL)0x3c000000,
    (FIXP_DBL)0x45ffffff, (FIXP_DBL)0x4fffffff, (FIXP_DBL)0x59ffffff,
    (FIXP_DBL)0x63ffffff};

static const FIXP_DBL iccQuant[8] = {
    (FIXP_DBL)0x7fffffff, (FIXP_DBL)0x77ef9d7f, (FIXP_DBL)0x6babc97f,
    (FIXP_DBL)0x4ceaf27f, (FIXP_DBL)0x2f0ed3c0, (FIXP_DBL)0x00000000,
    (FIXP_DBL)0xb49ba601, (FIXP_DBL)0x80000000};

static FDK_PSENC_ERROR InitPSData(HANDLE_PS_DATA hPsData) {
  FDK_PSENC_ERROR error = PSENC_OK;

  if (hPsData == NULL) {
    error = PSENC_INVALID_HANDLE;
  } else {
    int i, env;
    FDKmemclear(hPsData, sizeof(PS_DATA));

    for (i = 0; i < PS_MAX_BANDS; i++) {
      hPsData->iidIdxLast[i] = 0;
      hPsData->iccIdxLast[i] = 0;
    }

    hPsData->iidEnable = hPsData->iidEnableLast = 0;
    hPsData->iccEnable = hPsData->iccEnableLast = 0;
    hPsData->iidQuantMode = hPsData->iidQuantModeLast = PS_IID_RES_COARSE;
    hPsData->iccQuantMode = hPsData->iccQuantModeLast = PS_ICC_ROT_A;

    for (env = 0; env < PS_MAX_ENVELOPES; env++) {
      hPsData->iccDiffMode[env] = PS_DELTA_FREQ;
      hPsData->iccDiffMode[env] = PS_DELTA_FREQ;

      for (i = 0; i < PS_MAX_BANDS; i++) {
        hPsData->iidIdx[env][i] = 0;
        hPsData->iccIdx[env][i] = 0;
      }
    }

    hPsData->nEnvelopesLast = 0;

    hPsData->headerCnt = MAX_PS_NOHEADER_CNT;
    hPsData->iidTimeCnt = MAX_TIME_DIFF_FRAMES;
    hPsData->iccTimeCnt = MAX_TIME_DIFF_FRAMES;
    hPsData->noEnvCnt = MAX_NOENV_CNT;
  }

  return error;
}

static FIXP_DBL quantizeCoef(const FIXP_DBL *RESTRICT input, const INT nBands,
                             const FIXP_DBL *RESTRICT quantTable,
                             const INT idxOffset, const INT nQuantSteps,
                             INT *RESTRICT quantOut) {
  INT idx, band;
  FIXP_DBL quantErr = FL2FXCONST_DBL(0.f);

  for (band = 0; band < nBands; band++) {
    for (idx = 0; idx < nQuantSteps - 1; idx++) {
      if (fixp_abs((input[band] >> 1) - (quantTable[idx + 1] >> 1)) >
          fixp_abs((input[band] >> 1) - (quantTable[idx] >> 1))) {
        break;
      }
    }
    quantErr += (fixp_abs(input[band] - quantTable[idx]) >>
                 PS_QUANT_SCALE); /* don't scale before subtraction; diff
                                     smaller (64-25)/64 */
    quantOut[band] = idx - idxOffset;
  }

  return quantErr;
}

static INT getICCMode(const INT nBands, const INT rotType) {
  INT mode = 0;

  switch (nBands) {
    case PS_BANDS_COARSE:
      mode = PS_RES_COARSE;
      break;
    case PS_BANDS_MID:
      mode = PS_RES_MID;
      break;
    default:
      mode = 0;
  }
  if (rotType == PS_ICC_ROT_B) {
    mode += 3;
  }

  return mode;
}

static INT getIIDMode(const INT nBands, const INT iidRes) {
  INT mode = 0;

  switch (nBands) {
    case PS_BANDS_COARSE:
      mode = PS_RES_COARSE;
      break;
    case PS_BANDS_MID:
      mode = PS_RES_MID;
      break;
    default:
      mode = 0;
      break;
  }

  if (iidRes == PS_IID_RES_FINE) {
    mode += 3;
  }

  return mode;
}

static INT envelopeReducible(FIXP_DBL iid[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                             FIXP_DBL icc[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                             INT psBands, INT nEnvelopes) {
#define THRESH_SCALE 7

  INT reducible = 1; /* true */
  INT e = 0, b = 0;
  FIXP_DBL dIid = FL2FXCONST_DBL(0.f);
  FIXP_DBL dIcc = FL2FXCONST_DBL(0.f);

  FIXP_DBL iidErrThreshold, iccErrThreshold;
  FIXP_DBL iidMeanError, iccMeanError;

  /* square values to prevent sqrt,
     multiply bands to prevent division; bands shifted DFRACT_BITS instead
     (DFRACT_BITS-1) because fMultDiv2 used*/
  iidErrThreshold =
      fMultDiv2(FL2FXCONST_DBL(6.5f * 6.5f / (IID_SCALE_FT * IID_SCALE_FT)),
                (FIXP_DBL)(psBands << ((DFRACT_BITS)-THRESH_SCALE)));
  iccErrThreshold =
      fMultDiv2(FL2FXCONST_DBL(0.75f * 0.75f),
                (FIXP_DBL)(psBands << ((DFRACT_BITS)-THRESH_SCALE)));

  if (nEnvelopes <= 1) {
    reducible = 0;
  } else {
    /* mean error criterion */
    for (e = 0; (e < nEnvelopes / 2) && (reducible != 0); e++) {
      iidMeanError = iccMeanError = FL2FXCONST_DBL(0.f);
      for (b = 0; b < psBands; b++) {
        dIid = (iid[2 * e][b] >> 1) -
               (iid[2 * e + 1][b] >> 1); /* scale 1 bit; squared -> 2 bit */
        dIcc = (icc[2 * e][b] >> 1) - (icc[2 * e + 1][b] >> 1);
        iidMeanError += fPow2Div2(dIid) >> (5 - 1); /* + (bands=20) scale = 5 */
        iccMeanError += fPow2Div2(dIcc) >> (5 - 1);
      } /* --> scaling = 7 bit = THRESH_SCALE !! */

      /* instead sqrt values are squared!
         instead of division, multiply threshold with psBands
         scaling necessary!! */

      /* quit as soon as threshold is reached */
      if ((iidMeanError > (iidErrThreshold)) ||
          (iccMeanError > (iccErrThreshold))) {
        reducible = 0;
      }
    }
  } /* nEnvelopes != 1 */

  return reducible;
}

static void processIidData(PS_DATA *psData,
                           FIXP_DBL iid[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                           const INT psBands, const INT nEnvelopes,
                           const FIXP_DBL quantErrorThreshold) {
  INT iidIdxFine[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  INT iidIdxCoarse[PS_MAX_ENVELOPES][PS_MAX_BANDS];

  FIXP_DBL errIID = FL2FXCONST_DBL(0.f);
  FIXP_DBL errIIDFine = FL2FXCONST_DBL(0.f);
  INT bitsIidFreq = 0;
  INT bitsIidTime = 0;
  INT bitsFineTot = 0;
  INT bitsCoarseTot = 0;
  INT error = 0;
  INT env, band;
  INT diffMode[PS_MAX_ENVELOPES], diffModeFine[PS_MAX_ENVELOPES];
  INT loudnDiff = 0;
  INT iidTransmit = 0;

  /* Quantize IID coefficients */
  for (env = 0; env < nEnvelopes; env++) {
    errIID +=
        quantizeCoef(iid[env], psBands, iidQuant_fx, 7, 15, iidIdxCoarse[env]);
    errIIDFine += quantizeCoef(iid[env], psBands, iidQuantFine_fx, 15, 31,
                               iidIdxFine[env]);
  }

  /* normalize error to number of envelopes, ps bands
     errIID /= psBands*nEnvelopes;
     errIIDFine /= psBands*nEnvelopes; */

  /* Check if IID coefficients should be used in this frame */
  psData->iidEnable = 0;
  for (env = 0; env < nEnvelopes; env++) {
    for (band = 0; band < psBands; band++) {
      loudnDiff += fixp_abs(iidIdxCoarse[env][band]);
      iidTransmit++;
    }
  }

  if (loudnDiff >
      fMultI(FL2FXCONST_DBL(0.7f), iidTransmit)) { /* 0.7f empiric value */
    psData->iidEnable = 1;
  }

  /* if iid not active -> RESET data */
  if (psData->iidEnable == 0) {
    psData->iidTimeCnt = MAX_TIME_DIFF_FRAMES;
    for (env = 0; env < nEnvelopes; env++) {
      psData->iidDiffMode[env] = PS_DELTA_FREQ;
      FDKmemclear(psData->iidIdx[env], sizeof(INT) * psBands);
    }
    return;
  }

  /* count COARSE quantization bits for first envelope*/
  bitsIidFreq = FDKsbrEnc_EncodeIid(NULL, iidIdxCoarse[0], NULL, psBands,
                                    PS_IID_RES_COARSE, PS_DELTA_FREQ, &error);

  if ((psData->iidTimeCnt >= MAX_TIME_DIFF_FRAMES) ||
      (psData->iidQuantModeLast == PS_IID_RES_FINE)) {
    bitsIidTime = DO_NOT_USE_THIS_MODE;
  } else {
    bitsIidTime =
        FDKsbrEnc_EncodeIid(NULL, iidIdxCoarse[0], psData->iidIdxLast, psBands,
                            PS_IID_RES_COARSE, PS_DELTA_TIME, &error);
  }

  /* decision DELTA_FREQ vs DELTA_TIME */
  if (bitsIidTime > bitsIidFreq) {
    diffMode[0] = PS_DELTA_FREQ;
    bitsCoarseTot = bitsIidFreq;
  } else {
    diffMode[0] = PS_DELTA_TIME;
    bitsCoarseTot = bitsIidTime;
  }

  /* count COARSE quantization bits for following envelopes*/
  for (env = 1; env < nEnvelopes; env++) {
    bitsIidFreq = FDKsbrEnc_EncodeIid(NULL, iidIdxCoarse[env], NULL, psBands,
                                      PS_IID_RES_COARSE, PS_DELTA_FREQ, &error);
    bitsIidTime =
        FDKsbrEnc_EncodeIid(NULL, iidIdxCoarse[env], iidIdxCoarse[env - 1],
                            psBands, PS_IID_RES_COARSE, PS_DELTA_TIME, &error);

    /* decision DELTA_FREQ vs DELTA_TIME */
    if (bitsIidTime > bitsIidFreq) {
      diffMode[env] = PS_DELTA_FREQ;
      bitsCoarseTot += bitsIidFreq;
    } else {
      diffMode[env] = PS_DELTA_TIME;
      bitsCoarseTot += bitsIidTime;
    }
  }

  /* count FINE quantization bits for first envelope*/
  bitsIidFreq = FDKsbrEnc_EncodeIid(NULL, iidIdxFine[0], NULL, psBands,
                                    PS_IID_RES_FINE, PS_DELTA_FREQ, &error);

  if ((psData->iidTimeCnt >= MAX_TIME_DIFF_FRAMES) ||
      (psData->iidQuantModeLast == PS_IID_RES_COARSE)) {
    bitsIidTime = DO_NOT_USE_THIS_MODE;
  } else {
    bitsIidTime =
        FDKsbrEnc_EncodeIid(NULL, iidIdxFine[0], psData->iidIdxLast, psBands,
                            PS_IID_RES_FINE, PS_DELTA_TIME, &error);
  }

  /* decision DELTA_FREQ vs DELTA_TIME */
  if (bitsIidTime > bitsIidFreq) {
    diffModeFine[0] = PS_DELTA_FREQ;
    bitsFineTot = bitsIidFreq;
  } else {
    diffModeFine[0] = PS_DELTA_TIME;
    bitsFineTot = bitsIidTime;
  }

  /* count FINE quantization bits for following envelopes*/
  for (env = 1; env < nEnvelopes; env++) {
    bitsIidFreq = FDKsbrEnc_EncodeIid(NULL, iidIdxFine[env], NULL, psBands,
                                      PS_IID_RES_FINE, PS_DELTA_FREQ, &error);
    bitsIidTime =
        FDKsbrEnc_EncodeIid(NULL, iidIdxFine[env], iidIdxFine[env - 1], psBands,
                            PS_IID_RES_FINE, PS_DELTA_TIME, &error);

    /* decision DELTA_FREQ vs DELTA_TIME */
    if (bitsIidTime > bitsIidFreq) {
      diffModeFine[env] = PS_DELTA_FREQ;
      bitsFineTot += bitsIidFreq;
    } else {
      diffModeFine[env] = PS_DELTA_TIME;
      bitsFineTot += bitsIidTime;
    }
  }

  if (bitsFineTot == bitsCoarseTot) {
    /* if same number of bits is needed, use the quantization with lower error
     */
    if (errIIDFine < errIID) {
      bitsCoarseTot = DO_NOT_USE_THIS_MODE;
    } else {
      bitsFineTot = DO_NOT_USE_THIS_MODE;
    }
  } else {
    /* const FIXP_DBL minThreshold =
     * FL2FXCONST_DBL(0.2f/(IID_SCALE_FT*PS_QUANT_SCALE_FT)*(psBands*nEnvelopes));
     */
    const FIXP_DBL minThreshold =
        (FIXP_DBL)((LONG)0x00019999 * (psBands * nEnvelopes));

    /* decision RES_FINE vs RES_COARSE                 */
    /* test if errIIDFine*quantErrorThreshold < errIID */
    /* shiftVal 2 comes from scaling of quantErrorThreshold */
    if (fixMax(((errIIDFine >> 1) + (minThreshold >> 1)) >> 1,
               fMult(quantErrorThreshold, errIIDFine)) < (errIID >> 2)) {
      bitsCoarseTot = DO_NOT_USE_THIS_MODE;
    } else if (fixMax(((errIID >> 1) + (minThreshold >> 1)) >> 1,
                      fMult(quantErrorThreshold, errIID)) < (errIIDFine >> 2)) {
      bitsFineTot = DO_NOT_USE_THIS_MODE;
    }
  }

  /* decision RES_FINE vs RES_COARSE */
  if (bitsFineTot < bitsCoarseTot) {
    psData->iidQuantMode = PS_IID_RES_FINE;
    for (env = 0; env < nEnvelopes; env++) {
      psData->iidDiffMode[env] = diffModeFine[env];
      FDKmemcpy(psData->iidIdx[env], iidIdxFine[env], psBands * sizeof(INT));
    }
  } else {
    psData->iidQuantMode = PS_IID_RES_COARSE;
    for (env = 0; env < nEnvelopes; env++) {
      psData->iidDiffMode[env] = diffMode[env];
      FDKmemcpy(psData->iidIdx[env], iidIdxCoarse[env], psBands * sizeof(INT));
    }
  }

  /* Count DELTA_TIME encoding streaks */
  for (env = 0; env < nEnvelopes; env++) {
    if (psData->iidDiffMode[env] == PS_DELTA_TIME)
      psData->iidTimeCnt++;
    else
      psData->iidTimeCnt = 0;
  }
}

static INT similarIid(PS_DATA *psData, const INT psBands,
                      const INT nEnvelopes) {
  const INT diffThr = (psData->iidQuantMode == PS_IID_RES_COARSE) ? 2 : 3;
  const INT sumDiffThr = diffThr * psBands / 4;
  INT similar = 0;
  INT diff = 0;
  INT sumDiff = 0;
  INT env = 0;
  INT b = 0;
  if ((nEnvelopes == psData->nEnvelopesLast) && (nEnvelopes == 1)) {
    similar = 1;
    for (env = 0; env < nEnvelopes; env++) {
      sumDiff = 0;
      b = 0;
      do {
        diff = fixp_abs(psData->iidIdx[env][b] - psData->iidIdxLast[b]);
        sumDiff += diff;
        if ((diff > diffThr) /* more than x quantization steps in any band */
            || (sumDiff > sumDiffThr)) { /* more than x quantisations steps
                                            overall difference */
          similar = 0;
        }
        b++;
      } while ((b < psBands) && (similar > 0));
    }
  } /* nEnvelopes==1  */

  return similar;
}

static INT similarIcc(PS_DATA *psData, const INT psBands,
                      const INT nEnvelopes) {
  const INT diffThr = 2;
  const INT sumDiffThr = diffThr * psBands / 4;
  INT similar = 0;
  INT diff = 0;
  INT sumDiff = 0;
  INT env = 0;
  INT b = 0;
  if ((nEnvelopes == psData->nEnvelopesLast) && (nEnvelopes == 1)) {
    similar = 1;
    for (env = 0; env < nEnvelopes; env++) {
      sumDiff = 0;
      b = 0;
      do {
        diff = fixp_abs(psData->iccIdx[env][b] - psData->iccIdxLast[b]);
        sumDiff += diff;
        if ((diff > diffThr) /* more than x quantisation step in any band */
            || (sumDiff > sumDiffThr)) { /* more than x quantisations steps
                                            overall difference */
          similar = 0;
        }
        b++;
      } while ((b < psBands) && (similar > 0));
    }
  } /* nEnvelopes==1  */

  return similar;
}

static void processIccData(
    PS_DATA *psData,
    FIXP_DBL icc[PS_MAX_ENVELOPES][PS_MAX_BANDS], /* const input values:
                                                     unable to declare as
                                                     const, since it does
                                                     not poINT to const
                                                     memory */
    const INT psBands, const INT nEnvelopes) {
  FIXP_DBL errICC = FL2FXCONST_DBL(0.f);
  INT env, band;
  INT bitsIccFreq, bitsIccTime;
  INT error = 0;
  INT inCoherence = 0, iccTransmit = 0;
  INT *iccIdxLast;

  iccIdxLast = psData->iccIdxLast;

  /* Quantize ICC coefficients */
  for (env = 0; env < nEnvelopes; env++) {
    errICC +=
        quantizeCoef(icc[env], psBands, iccQuant, 0, 8, psData->iccIdx[env]);
  }

  /* Check if ICC coefficients should be used */
  psData->iccEnable = 0;
  for (env = 0; env < nEnvelopes; env++) {
    for (band = 0; band < psBands; band++) {
      inCoherence += psData->iccIdx[env][band];
      iccTransmit++;
    }
  }
  if (inCoherence >
      fMultI(FL2FXCONST_DBL(0.5f), iccTransmit)) { /* 0.5f empiric value */
    psData->iccEnable = 1;
  }

  if (psData->iccEnable == 0) {
    psData->iccTimeCnt = MAX_TIME_DIFF_FRAMES;
    for (env = 0; env < nEnvelopes; env++) {
      psData->iccDiffMode[env] = PS_DELTA_FREQ;
      FDKmemclear(psData->iccIdx[env], sizeof(INT) * psBands);
    }
    return;
  }

  for (env = 0; env < nEnvelopes; env++) {
    bitsIccFreq = FDKsbrEnc_EncodeIcc(NULL, psData->iccIdx[env], NULL, psBands,
                                      PS_DELTA_FREQ, &error);

    if (psData->iccTimeCnt < MAX_TIME_DIFF_FRAMES) {
      bitsIccTime = FDKsbrEnc_EncodeIcc(NULL, psData->iccIdx[env], iccIdxLast,
                                        psBands, PS_DELTA_TIME, &error);
    } else {
      bitsIccTime = DO_NOT_USE_THIS_MODE;
    }

    if (bitsIccFreq > bitsIccTime) {
      psData->iccDiffMode[env] = PS_DELTA_TIME;
      psData->iccTimeCnt++;
    } else {
      psData->iccDiffMode[env] = PS_DELTA_FREQ;
      psData->iccTimeCnt = 0;
    }
    iccIdxLast = psData->iccIdx[env];
  }
}

static void calculateIID(FIXP_DBL ldPwrL[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL ldPwrR[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL iid[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         INT nEnvelopes, INT psBands) {
  INT i = 0;
  INT env = 0;
  for (env = 0; env < nEnvelopes; env++) {
    for (i = 0; i < psBands; i++) {
      /* iid[env][i] = 10.0f*(float)log10(pwrL[env][i]/pwrR[env][i]);
       */
      FIXP_DBL IID = fMultDiv2(FL2FXCONST_DBL(LOG10_2_10 / IID_SCALE_FT),
                               (ldPwrL[env][i] - ldPwrR[env][i]));

      IID = fixMin(IID, (FIXP_DBL)(MAXVAL_DBL >> (LD_DATA_SHIFT + 1)));
      IID = fixMax(IID, (FIXP_DBL)(MINVAL_DBL >> (LD_DATA_SHIFT + 1)));
      iid[env][i] = IID << (LD_DATA_SHIFT + 1);
    }
  }
}

static void calculateICC(FIXP_DBL pwrL[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL pwrR[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL pwrCr[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL pwrCi[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         FIXP_DBL icc[PS_MAX_ENVELOPES][PS_MAX_BANDS],
                         INT nEnvelopes, INT psBands) {
  INT i = 0;
  INT env = 0;
  INT border = psBands;

  switch (psBands) {
    case PS_BANDS_COARSE:
      border = 5;
      break;
    case PS_BANDS_MID:
      border = 11;
      break;
    default:
      break;
  }

  for (env = 0; env < nEnvelopes; env++) {
    for (i = 0; i < border; i++) {
      /* icc[env][i] = min( pwrCr[env][i] / (float) sqrt(pwrL[env][i] *
       * pwrR[env][i]) , 1.f);
       */
      int scale;
      FIXP_DBL invNrg = invSqrtNorm2(
          fMax(fMult(pwrL[env][i], pwrR[env][i]), (FIXP_DBL)1), &scale);
      icc[env][i] =
          SATURATE_LEFT_SHIFT(fMult(pwrCr[env][i], invNrg), scale, DFRACT_BITS);
    }

    for (; i < psBands; i++) {
      int denom_e;
      FIXP_DBL denom_m = fMultNorm(pwrL[env][i], pwrR[env][i], &denom_e);

      if (denom_m == (FIXP_DBL)0) {
        icc[env][i] = (FIXP_DBL)MAXVAL_DBL;
      } else {
        int num_e, result_e;
        FIXP_DBL num_m, result_m;

        num_e = CountLeadingBits(
            fixMax(fixp_abs(pwrCr[env][i]), fixp_abs(pwrCi[env][i])));
        num_m = fPow2Div2((pwrCr[env][i] << num_e)) +
                fPow2Div2((pwrCi[env][i] << num_e));

        result_m = fDivNorm(num_m, denom_m, &result_e);
        result_e += (-2 * num_e + 1) - denom_e;
        icc[env][i] = scaleValueSaturate(sqrtFixp(result_m >> (result_e & 1)),
                                         (result_e + (result_e & 1)) >> 1);
      }
    }
  }
}

void FDKsbrEnc_initPsBandNrgScale(HANDLE_PS_ENCODE hPsEncode) {
  INT group, bin;
  INT nIidGroups = hPsEncode->nQmfIidGroups + hPsEncode->nSubQmfIidGroups;

  FDKmemclear(hPsEncode->psBandNrgScale, PS_MAX_BANDS * sizeof(SCHAR));

  for (group = 0; group < nIidGroups; group++) {
    /* Translate group to bin */
    bin = hPsEncode->subband2parameterIndex[group];

    /* Translate from 20 bins to 10 bins */
    if (hPsEncode->psEncMode == PS_BANDS_COARSE) {
      bin = bin >> 1;
    }

    hPsEncode->psBandNrgScale[bin] =
        (hPsEncode->psBandNrgScale[bin] == 0)
            ? (hPsEncode->iidGroupWidthLd[group] + 5)
            : (fixMax(hPsEncode->iidGroupWidthLd[group],
                      hPsEncode->psBandNrgScale[bin]) +
               1);
  }
}

FDK_PSENC_ERROR FDKsbrEnc_CreatePSEncode(HANDLE_PS_ENCODE *phPsEncode) {
  FDK_PSENC_ERROR error = PSENC_OK;

  if (phPsEncode == NULL) {
    error = PSENC_INVALID_HANDLE;
  } else {
    HANDLE_PS_ENCODE hPsEncode = NULL;
    if (NULL == (hPsEncode = GetRam_PsEncode())) {
      error = PSENC_MEMORY_ERROR;
      goto bail;
    }
    FDKmemclear(hPsEncode, sizeof(PS_ENCODE));
    *phPsEncode = hPsEncode; /* return allocated handle */
  }
bail:
  return error;
}

FDK_PSENC_ERROR FDKsbrEnc_InitPSEncode(HANDLE_PS_ENCODE hPsEncode,
                                       const PS_BANDS psEncMode,
                                       const FIXP_DBL iidQuantErrorThreshold) {
  FDK_PSENC_ERROR error = PSENC_OK;

  if (NULL == hPsEncode) {
    error = PSENC_INVALID_HANDLE;
  } else {
    if (PSENC_OK != (InitPSData(&hPsEncode->psData))) {
      goto bail;
    }

    switch (psEncMode) {
      case PS_BANDS_COARSE:
      case PS_BANDS_MID:
        hPsEncode->nQmfIidGroups = QMF_GROUPS_LO_RES;
        hPsEncode->nSubQmfIidGroups = SUBQMF_GROUPS_LO_RES;
        FDKmemcpy(hPsEncode->iidGroupBorders, iidGroupBordersLoRes,
                  (hPsEncode->nQmfIidGroups + hPsEncode->nSubQmfIidGroups + 1) *
                      sizeof(INT));
        FDKmemcpy(hPsEncode->subband2parameterIndex, subband2parameter20,
                  (hPsEncode->nQmfIidGroups + hPsEncode->nSubQmfIidGroups) *
                      sizeof(INT));
        FDKmemcpy(hPsEncode->iidGroupWidthLd, iidGroupWidthLdLoRes,
                  (hPsEncode->nQmfIidGroups + hPsEncode->nSubQmfIidGroups) *
                      sizeof(UCHAR));
        break;
      default:
        error = PSENC_INIT_ERROR;
        goto bail;
    }

    hPsEncode->psEncMode = psEncMode;
    hPsEncode->iidQuantErrorThreshold = iidQuantErrorThreshold;
    FDKsbrEnc_initPsBandNrgScale(hPsEncode);
  }
bail:
  return error;
}

FDK_PSENC_ERROR FDKsbrEnc_DestroyPSEncode(HANDLE_PS_ENCODE *phPsEncode) {
  FDK_PSENC_ERROR error = PSENC_OK;

  if (NULL != phPsEncode) {
    FreeRam_PsEncode(phPsEncode);
  }

  return error;
}

typedef struct {
  FIXP_DBL pwrL[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL pwrR[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL ldPwrL[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL ldPwrR[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL pwrCr[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL pwrCi[PS_MAX_ENVELOPES][PS_MAX_BANDS];

} PS_PWR_DATA;

FDK_PSENC_ERROR FDKsbrEnc_PSEncode(
    HANDLE_PS_ENCODE hPsEncode, HANDLE_PS_OUT hPsOut, UCHAR *dynBandScale,
    UINT maxEnvelopes,
    FIXP_DBL *hybridData[HYBRID_FRAMESIZE][MAX_PS_CHANNELS][2],
    const INT frameSize, const INT sendHeader) {
  FDK_PSENC_ERROR error = PSENC_OK;

  HANDLE_PS_DATA hPsData = &hPsEncode->psData;
  FIXP_DBL iid[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  FIXP_DBL icc[PS_MAX_ENVELOPES][PS_MAX_BANDS];
  int envBorder[PS_MAX_ENVELOPES + 1];

  int group, bin, col, subband, band;
  int i = 0;

  int env = 0;
  int psBands = (int)hPsEncode->psEncMode;
  int nIidGroups = hPsEncode->nQmfIidGroups + hPsEncode->nSubQmfIidGroups;
  int nEnvelopes = fixMin(maxEnvelopes, (UINT)PS_MAX_ENVELOPES);

  C_ALLOC_SCRATCH_START(pwrData, PS_PWR_DATA, 1)

  for (env = 0; env < nEnvelopes + 1; env++) {
    envBorder[env] = fMultI(GetInvInt(nEnvelopes), frameSize * env);
  }

  for (env = 0; env < nEnvelopes; env++) {
    /* clear energy array */
    for (band = 0; band < psBands; band++) {
      pwrData->pwrL[env][band] = pwrData->pwrR[env][band] =
          pwrData->pwrCr[env][band] = pwrData->pwrCi[env][band] = FIXP_DBL(1);
    }

    /**** calculate energies and correlation ****/

    /* start with hybrid data */
    for (group = 0; group < nIidGroups; group++) {
      /* Translate group to bin */
      bin = hPsEncode->subband2parameterIndex[group];

      /* Translate from 20 bins to 10 bins */
      if (hPsEncode->psEncMode == PS_BANDS_COARSE) {
        bin >>= 1;
      }

      /* determine group border */
      int bScale = hPsEncode->psBandNrgScale[bin];

      FIXP_DBL pwrL_env_bin = pwrData->pwrL[env][bin];
      FIXP_DBL pwrR_env_bin = pwrData->pwrR[env][bin];
      FIXP_DBL pwrCr_env_bin = pwrData->pwrCr[env][bin];
      FIXP_DBL pwrCi_env_bin = pwrData->pwrCi[env][bin];

      int scale = (int)dynBandScale[bin];
      for (col = envBorder[env]; col < envBorder[env + 1]; col++) {
        for (subband = hPsEncode->iidGroupBorders[group];
             subband < hPsEncode->iidGroupBorders[group + 1]; subband++) {
          FIXP_DBL l_real = (hybridData[col][0][0][subband]) << scale;
          FIXP_DBL l_imag = (hybridData[col][0][1][subband]) << scale;
          FIXP_DBL r_real = (hybridData[col][1][0][subband]) << scale;
          FIXP_DBL r_imag = (hybridData[col][1][1][subband]) << scale;

          pwrL_env_bin += (fPow2Div2(l_real) + fPow2Div2(l_imag)) >> bScale;
          pwrR_env_bin += (fPow2Div2(r_real) + fPow2Div2(r_imag)) >> bScale;
          pwrCr_env_bin +=
              (fMultDiv2(l_real, r_real) + fMultDiv2(l_imag, r_imag)) >> bScale;
          pwrCi_env_bin +=
              (fMultDiv2(r_real, l_imag) - fMultDiv2(l_real, r_imag)) >> bScale;
        }
      }
      /* assure, nrg's of left and right channel are not negative; necessary on
       * 16 bit multiply units */
      pwrData->pwrL[env][bin] = fixMax((FIXP_DBL)0, pwrL_env_bin);
      pwrData->pwrR[env][bin] = fixMax((FIXP_DBL)0, pwrR_env_bin);

      pwrData->pwrCr[env][bin] = pwrCr_env_bin;
      pwrData->pwrCi[env][bin] = pwrCi_env_bin;

    } /* nIidGroups */

    /* calc logarithmic energy */
    LdDataVector(pwrData->pwrL[env], pwrData->ldPwrL[env], psBands);
    LdDataVector(pwrData->pwrR[env], pwrData->ldPwrR[env], psBands);

  } /* nEnvelopes */

  /* calculate iid and icc */
  calculateIID(pwrData->ldPwrL, pwrData->ldPwrR, iid, nEnvelopes, psBands);
  calculateICC(pwrData->pwrL, pwrData->pwrR, pwrData->pwrCr, pwrData->pwrCi,
               icc, nEnvelopes, psBands);

  /*** Envelope Reduction ***/
  while (envelopeReducible(iid, icc, psBands, nEnvelopes)) {
    int e = 0;
    /* sum energies of two neighboring envelopes */
    nEnvelopes >>= 1;
    for (e = 0; e < nEnvelopes; e++) {
      FDKsbrEnc_addFIXP_DBL(pwrData->pwrL[2 * e], pwrData->pwrL[2 * e + 1],
                            pwrData->pwrL[e], psBands);
      FDKsbrEnc_addFIXP_DBL(pwrData->pwrR[2 * e], pwrData->pwrR[2 * e + 1],
                            pwrData->pwrR[e], psBands);
      FDKsbrEnc_addFIXP_DBL(pwrData->pwrCr[2 * e], pwrData->pwrCr[2 * e + 1],
                            pwrData->pwrCr[e], psBands);
      FDKsbrEnc_addFIXP_DBL(pwrData->pwrCi[2 * e], pwrData->pwrCi[2 * e + 1],
                            pwrData->pwrCi[e], psBands);

      /* calc logarithmic energy */
      LdDataVector(pwrData->pwrL[e], pwrData->ldPwrL[e], psBands);
      LdDataVector(pwrData->pwrR[e], pwrData->ldPwrR[e], psBands);

      /* reduce number of envelopes and adjust borders */
      envBorder[e] = envBorder[2 * e];
    }
    envBorder[nEnvelopes] = envBorder[2 * nEnvelopes];

    /* re-calculate iid and icc */
    calculateIID(pwrData->ldPwrL, pwrData->ldPwrR, iid, nEnvelopes, psBands);
    calculateICC(pwrData->pwrL, pwrData->pwrR, pwrData->pwrCr, pwrData->pwrCi,
                 icc, nEnvelopes, psBands);
  }

  /*  */
  if (sendHeader) {
    hPsData->headerCnt = MAX_PS_NOHEADER_CNT;
    hPsData->iidTimeCnt = MAX_TIME_DIFF_FRAMES;
    hPsData->iccTimeCnt = MAX_TIME_DIFF_FRAMES;
    hPsData->noEnvCnt = MAX_NOENV_CNT;
  }

  /*** Parameter processing, quantisation etc ***/
  processIidData(hPsData, iid, psBands, nEnvelopes,
                 hPsEncode->iidQuantErrorThreshold);
  processIccData(hPsData, icc, psBands, nEnvelopes);

  /*** Initialize output struct ***/

  /* PS Header on/off ? */
  if ((hPsData->headerCnt < MAX_PS_NOHEADER_CNT) &&
      ((hPsData->iidQuantMode == hPsData->iidQuantModeLast) &&
       (hPsData->iccQuantMode == hPsData->iccQuantModeLast)) &&
      ((hPsData->iidEnable == hPsData->iidEnableLast) &&
       (hPsData->iccEnable == hPsData->iccEnableLast))) {
    hPsOut->enablePSHeader = 0;
  } else {
    hPsOut->enablePSHeader = 1;
    hPsData->headerCnt = 0;
  }

  /* nEnvelopes = 0 ? */
  if ((hPsData->noEnvCnt < MAX_NOENV_CNT) &&
      (similarIid(hPsData, psBands, nEnvelopes)) &&
      (similarIcc(hPsData, psBands, nEnvelopes))) {
    hPsOut->nEnvelopes = nEnvelopes = 0;
    hPsData->noEnvCnt++;
  } else {
    hPsData->noEnvCnt = 0;
  }

  if (nEnvelopes > 0) {
    hPsOut->enableIID = hPsData->iidEnable;
    hPsOut->iidMode = getIIDMode(psBands, hPsData->iidQuantMode);

    hPsOut->enableICC = hPsData->iccEnable;
    hPsOut->iccMode = getICCMode(psBands, hPsData->iccQuantMode);

    hPsOut->enableIpdOpd = 0;
    hPsOut->frameClass = 0;
    hPsOut->nEnvelopes = nEnvelopes;

    for (env = 0; env < nEnvelopes; env++) {
      hPsOut->frameBorder[env] = envBorder[env + 1];
      hPsOut->deltaIID[env] = (PS_DELTA)hPsData->iidDiffMode[env];
      hPsOut->deltaICC[env] = (PS_DELTA)hPsData->iccDiffMode[env];
      for (band = 0; band < psBands; band++) {
        hPsOut->iid[env][band] = hPsData->iidIdx[env][band];
        hPsOut->icc[env][band] = hPsData->iccIdx[env][band];
      }
    }

    /* IPD OPD not supported right now */
    FDKmemclear(hPsOut->ipd,
                PS_MAX_ENVELOPES * PS_MAX_BANDS * sizeof(PS_DELTA));
    for (env = 0; env < PS_MAX_ENVELOPES; env++) {
      hPsOut->deltaIPD[env] = PS_DELTA_FREQ;
      hPsOut->deltaOPD[env] = PS_DELTA_FREQ;
    }

    FDKmemclear(hPsOut->ipdLast, PS_MAX_BANDS * sizeof(INT));
    FDKmemclear(hPsOut->opdLast, PS_MAX_BANDS * sizeof(INT));

    for (band = 0; band < PS_MAX_BANDS; band++) {
      hPsOut->iidLast[band] = hPsData->iidIdxLast[band];
      hPsOut->iccLast[band] = hPsData->iccIdxLast[band];
    }

    /* save iids and iccs for differential time coding in the next frame */
    hPsData->nEnvelopesLast = nEnvelopes;
    hPsData->iidEnableLast = hPsData->iidEnable;
    hPsData->iccEnableLast = hPsData->iccEnable;
    hPsData->iidQuantModeLast = hPsData->iidQuantMode;
    hPsData->iccQuantModeLast = hPsData->iccQuantMode;
    for (i = 0; i < psBands; i++) {
      hPsData->iidIdxLast[i] = hPsData->iidIdx[nEnvelopes - 1][i];
      hPsData->iccIdxLast[i] = hPsData->iccIdx[nEnvelopes - 1][i];
    }
  } /* Envelope > 0 */

  C_ALLOC_SCRATCH_END(pwrData, PS_PWR_DATA, 1)

  return error;
}