path: root/fdk-aac/libSACdec/src/sac_reshapeBBEnv.cpp

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

© Copyright  1995 - 2021 Fraunhofer-Gesellschaft zur Förderung der angewandten
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 1.    INTRODUCTION
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scheme for digital audio. This FDK AAC Codec software is intended to be used on
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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
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specifications.

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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 surround decoder library *************************

   Author(s):

   Description: SAC Dec guided envelope shaping

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

#include "sac_reshapeBBEnv.h"

#include "sac_dec.h"
#include "sac_bitdec.h"
#include "sac_calcM1andM2.h"
#include "sac_reshapeBBEnv.h"
#include "sac_rom.h"

#define INP_DRY_WET 0
#define INP_DMX 1

#define SF_SHAPE 1
#define SF_DIV32 6
#define SF_FACTOR_SLOT 5

#define START_BB_ENV 0 /* 10 */
#define END_BB_ENV 9   /* 18 */

#define SF_ALPHA1 8
#define SF_BETA1 4

void initBBEnv(spatialDec *self, int initStatesFlag) {
  INT ch, k;

  for (ch = 0; ch < self->numOutputChannels; ch++) {
    k = row2channelGES[self->treeConfig][ch];
    self->row2channelDmxGES[ch] = k;
    if (k == -1) continue;

    switch (self->treeConfig) {
      case TREE_212:
        self->row2channelDmxGES[ch] = 0;
        break;
      default:;
    }
  }

  if (initStatesFlag) {
    for (k = 0; k < 2 * MAX_OUTPUT_CHANNELS + MAX_INPUT_CHANNELS; k++) {
      self->reshapeBBEnvState->normNrgPrev__FDK[k] =
          FL2FXCONST_DBL(0.5f); /* 32768.f*32768.f */
      self->reshapeBBEnvState->normNrgPrevSF[k] = DFRACT_BITS - 1;
      self->reshapeBBEnvState->partNrgPrevSF[k] = 0;
      self->reshapeBBEnvState->partNrgPrev2SF[k] = 0;
      self->reshapeBBEnvState->frameNrgPrevSF[k] = 0;
    }
  }

  self->reshapeBBEnvState->alpha__FDK =
      FL2FXCONST_DBL(0.99637845575f); /* FDKexp(-64 / (0.4f  * 44100)) */
  self->reshapeBBEnvState->beta__FDK =
      FL2FXCONST_DBL(0.96436909488f); /* FDKexp(-64 / (0.04f * 44100)) */
}

static inline void getSlotNrgHQ(FIXP_DBL *RESTRICT pReal,
                                FIXP_DBL *RESTRICT pImag,
                                FIXP_DBL *RESTRICT slotNrg, INT maxValSF,
                                INT hybBands) {
  INT qs;
  FIXP_DBL nrg;

  /* qs = 12, 13, 14 */
  slotNrg[0] = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  slotNrg[1] = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  slotNrg[2] = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  /* qs = 15 */
  slotNrg[3] = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  /* qs = 16, 17 */
  nrg = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
         (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  slotNrg[4] =
      nrg + ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
             (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  /* qs = 18, 19, 20 */
  nrg = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
         (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  nrg += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
          (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  slotNrg[5] =
      nrg + ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
             (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  /* qs = 21, 22 */
  nrg = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
         (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  slotNrg[6] =
      nrg + ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
             (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
  /* qs = 23, 24 */
  if (hybBands > 23) {
    slotNrg[6] += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                   (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    slotNrg[6] += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
                   (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    /* qs = 25, 26, 29, 28, 29 */
    nrg = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
           (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    nrg += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
            (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    nrg += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
            (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    nrg += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
            (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    slotNrg[7] =
        nrg + ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
               (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    /* qs = 30 ... min(41,hybBands-1) */
    nrg = ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
           (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    for (qs = 31; qs < hybBands; qs++) {
      nrg += ((fPow2Div2((*pReal++) << maxValSF) >> (SF_FACTOR_SLOT - 1)) +
              (fPow2Div2((*pImag++) << maxValSF) >> (SF_FACTOR_SLOT - 1)));
    }
    slotNrg[8] = nrg;
  } else {
    slotNrg[7] = (FIXP_DBL)0;
    slotNrg[8] = (FIXP_DBL)0;
  }
}

static inline void combineDryWet(FIXP_DBL *RESTRICT pReal,
                                 FIXP_DBL *RESTRICT pImag,
                                 FIXP_DBL *RESTRICT pHybOutputRealDry,
                                 FIXP_DBL *RESTRICT pHybOutputImagDry,
                                 FIXP_DBL *RESTRICT pHybOutputRealWet,
                                 FIXP_DBL *RESTRICT pHybOutputImagWet,
                                 INT cplxBands, INT hybBands) {
  INT qs;

  for (qs = 12; qs < cplxBands; qs++) {
    pReal[qs] = (pHybOutputRealDry[qs] >> 1) + (pHybOutputRealWet[qs] >> 1);
    pImag[qs] = (pHybOutputImagDry[qs] >> 1) + (pHybOutputImagWet[qs] >> 1);
  }
  for (; qs < hybBands; qs++) {
    pReal[qs] = (pHybOutputRealDry[qs] >> 1) + (pHybOutputRealWet[qs] >> 1);
  }
}

static inline void slotAmp(
    FIXP_DBL *RESTRICT slotAmp_dry, INT *RESTRICT slotAmp_dry_e,
    FIXP_DBL *RESTRICT slotAmp_wet, INT *RESTRICT slotAmp_wet_e,
    FIXP_DBL *RESTRICT pHybOutputRealDry, FIXP_DBL *RESTRICT pHybOutputImagDry,
    FIXP_DBL *RESTRICT pHybOutputRealWet, FIXP_DBL *RESTRICT pHybOutputImagWet,
    INT cplxBands, INT hybBands) {
  INT qs, s1, s2, headroom_dry, headroom_wet;
  FIXP_DBL dry, wet;

  /* headroom can be reduced by 1 bit due to use of fPow2Div2 */
  s1 = DFRACT_BITS - 1 - CntLeadingZeros(hybBands + cplxBands);
  headroom_dry = fMin(getScalefactor(pHybOutputRealDry, hybBands),
                      getScalefactor(pHybOutputImagDry, cplxBands));
  headroom_wet = fMin(getScalefactor(pHybOutputRealWet, hybBands),
                      getScalefactor(pHybOutputImagWet, cplxBands));

  dry = wet = FL2FXCONST_DBL(0.0f);
  for (qs = 0; qs < cplxBands; qs++) {
    /* sum up dry part */
    dry += (fPow2Div2(pHybOutputRealDry[qs] << headroom_dry) >> s1);
    dry += (fPow2Div2(pHybOutputImagDry[qs] << headroom_dry) >> s1);
    /* sum up wet part */
    wet += (fPow2Div2(pHybOutputRealWet[qs] << headroom_wet) >> s1);
    wet += (fPow2Div2(pHybOutputImagWet[qs] << headroom_wet) >> s1);
  }
  for (; qs < hybBands; qs++) {
    dry += (fPow2Div2(pHybOutputRealDry[qs] << headroom_dry) >> s1);
    wet += (fPow2Div2(pHybOutputRealWet[qs] << headroom_wet) >> s1);
  }

  /* consider fPow2Div2() */
  s1 += 1;

  /* normalize dry part, ensure that exponent is even */
  s2 = fixMax(0, CntLeadingZeros(dry) - 1);
  *slotAmp_dry = dry << s2;
  *slotAmp_dry_e = s1 - s2 - 2 * headroom_dry;
  if (*slotAmp_dry_e & 1) {
    *slotAmp_dry = *slotAmp_dry >> 1;
    *slotAmp_dry_e += 1;
  }

  /* normalize wet part, ensure that exponent is even */
  s2 = fixMax(0, CntLeadingZeros(wet) - 1);
  *slotAmp_wet = wet << s2;
  *slotAmp_wet_e = s1 - s2 - 2 * headroom_wet;
  if (*slotAmp_wet_e & 1) {
    *slotAmp_wet = *slotAmp_wet >> 1;
    *slotAmp_wet_e += 1;
  }
}

#if defined(__aarch64__)
__attribute__((noinline))
#endif
static void
shapeBBEnv(FIXP_DBL *pHybOutputRealDry, FIXP_DBL *pHybOutputImagDry,
           FIXP_DBL dryFac, INT scale, INT cplxBands, INT hybBands) {
  INT qs;

  if (scale == 0) {
    for (qs = 0; qs < cplxBands; qs++) {
      pHybOutputRealDry[qs] = fMultDiv2(pHybOutputRealDry[qs], dryFac);
      pHybOutputImagDry[qs] = fMultDiv2(pHybOutputImagDry[qs], dryFac);
    }
    for (; qs < hybBands; qs++) {
      pHybOutputRealDry[qs] = fMultDiv2(pHybOutputRealDry[qs], dryFac);
    }
  } else {
    for (qs = 0; qs < cplxBands; qs++) {
      pHybOutputRealDry[qs] = SATURATE_LEFT_SHIFT(
          fMultDiv2(pHybOutputRealDry[qs], dryFac), scale, DFRACT_BITS);
      pHybOutputImagDry[qs] = SATURATE_LEFT_SHIFT(
          fMultDiv2(pHybOutputImagDry[qs], dryFac), scale, DFRACT_BITS);
    }
    for (; qs < hybBands; qs++) {
      pHybOutputRealDry[qs] = SATURATE_LEFT_SHIFT(
          fMultDiv2(pHybOutputRealDry[qs], dryFac), scale, DFRACT_BITS);
    }
  }
}

static void extractBBEnv(spatialDec *self, INT inp, INT start, INT channels,
                         FIXP_DBL *pEnv, const SPATIAL_BS_FRAME *frame) {
  INT ch, pb, prevChOffs;
  INT clz, scale, scale_min, envSF;
  INT scaleCur, scalePrev, commonScale;
  INT slotNrgSF, partNrgSF, frameNrgSF;
  INT *pPartNrgPrevSF, *pFrameNrgPrevSF;
  INT *pNormNrgPrevSF, *pPartNrgPrev2SF;

  FIXP_DBL maxVal, env, frameNrg, normNrg;
  FIXP_DBL *pReal, *pImag;
  FIXP_DBL *partNrg, *partNrgPrev;

  C_ALLOC_SCRATCH_START(pScratchBuffer, FIXP_DBL,
                        (2 * 42 + MAX_PARAMETER_BANDS));
  C_ALLOC_SCRATCH_START(resPb, FIXP_DBL, (END_BB_ENV - START_BB_ENV));
  C_ALLOC_SCRATCH_START(resPbSF, INT, (END_BB_ENV - START_BB_ENV));

  FIXP_DBL *slotNrg = pScratchBuffer + (2 * 42);

  RESHAPE_BBENV_STATE *pBBEnvState = self->reshapeBBEnvState;

  FIXP_DBL alpha = pBBEnvState->alpha__FDK;
  /*FIXP_DBL  alpha1 = (FL2FXCONST_DBL(1.0f) - alpha) << SF_ALPHA1;*/
  FIXP_DBL alpha1 = ((FIXP_DBL)MAXVAL_DBL - alpha) << SF_ALPHA1;
  FIXP_DBL beta = pBBEnvState->beta__FDK;
  /*FIXP_DBL  beta1  = (FL2FXCONST_DBL(1.0f) - beta) << SF_BETA1;*/
  FIXP_DBL beta1 = ((FIXP_DBL)MAXVAL_DBL - beta) << SF_BETA1;

  INT shapeActiv = 1;
  INT hybBands = fixMin(42, self->hybridBands);
  INT staticScale = self->staticDecScale + (1);
  INT cplxBands;
  cplxBands = fixMin(42, self->hybridBands);

  for (ch = start; ch < channels; ch++) {
    if (inp == INP_DRY_WET) {
      INT ch2 = row2channelGES[self->treeConfig][ch];
      if (ch2 == -1) {
        continue;
      } else {
        if (frame->tempShapeEnableChannelGES[ch2]) {
          shapeActiv = 1;
        } else {
          shapeActiv = 0;
        }
      }
      prevChOffs = ch;
      pReal = pScratchBuffer;
      pImag = pScratchBuffer + 42;
      combineDryWet(pReal, pImag, self->hybOutputRealDry__FDK[ch],
                    self->hybOutputImagDry__FDK[ch],
                    self->hybOutputRealWet__FDK[ch],
                    self->hybOutputImagWet__FDK[ch], cplxBands, hybBands);
      clz = fMin(getScalefactor(&pReal[12], fMax(0, hybBands - 12)),
                 getScalefactor(&pImag[12], fMax(0, cplxBands - 12)));
    } else {
      prevChOffs = ch + self->numOutputChannels;
      pReal = self->hybInputReal__FDK[ch];
      pImag = self->hybInputImag__FDK[ch];
      clz = fMin(getScalefactor(&pReal[12], fMax(0, hybBands - 12)),
                 getScalefactor(&pImag[12], fMax(0, cplxBands - 12)));
    }

    partNrg = partNrgPrev = pBBEnvState->partNrgPrev__FDK[prevChOffs];
    pPartNrgPrevSF = &pBBEnvState->partNrgPrevSF[prevChOffs];
    pFrameNrgPrevSF = &pBBEnvState->frameNrgPrevSF[prevChOffs];
    pNormNrgPrevSF = &pBBEnvState->normNrgPrevSF[prevChOffs];
    pPartNrgPrev2SF = &pBBEnvState->partNrgPrev2SF[prevChOffs];

    /* calculate slot energy */
    {
      getSlotNrgHQ(&pReal[12], &pImag[12], slotNrg, clz,
                   fixMin(42, self->hybridBands)); /* scale slotNrg:
                                                      2*(staticScale-clz) +
                                                      SF_FACTOR_SLOT */
    }

    slotNrgSF = 2 * (staticScale - clz + ((inp == INP_DRY_WET) ? 1 : 0)) +
                SF_FACTOR_SLOT;
    frameNrgSF = 2 * (staticScale - clz + ((inp == INP_DRY_WET) ? 1 : 0)) +
                 SF_FACTOR_SLOT;

    partNrgSF = fixMax(slotNrgSF - SF_ALPHA1 + 1,
                       pPartNrgPrevSF[0] - pPartNrgPrev2SF[0] + 1);
    scalePrev = fixMax(fixMin(partNrgSF - pPartNrgPrevSF[0], DFRACT_BITS - 1),
                       -(DFRACT_BITS - 1));
    scaleCur =
        fixMax(fixMin(partNrgSF - slotNrgSF + SF_ALPHA1, DFRACT_BITS - 1),
               -(DFRACT_BITS - 1));

    maxVal = FL2FXCONST_DBL(0.0f);
    frameNrg = FL2FXCONST_DBL(0.0f);
    if ((scaleCur < 0) && (scalePrev < 0)) {
      scaleCur = -scaleCur;
      scalePrev = -scalePrev;
      for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
        partNrg[pb] = ((fMultDiv2(alpha1, slotNrg[pb]) << scaleCur) +
                       (fMultDiv2(alpha, partNrgPrev[pb]) << scalePrev))
                      << 1;
        maxVal |= partNrg[pb];
        frameNrg += slotNrg[pb] >> 3;
      }
    } else if ((scaleCur >= 0) && (scalePrev >= 0)) {
      for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
        partNrg[pb] = ((fMultDiv2(alpha1, slotNrg[pb]) >> scaleCur) +
                       (fMultDiv2(alpha, partNrgPrev[pb]) >> scalePrev))
                      << 1;
        maxVal |= partNrg[pb];
        frameNrg += slotNrg[pb] >> 3;
      }
    } else if ((scaleCur < 0) && (scalePrev >= 0)) {
      scaleCur = -scaleCur;
      for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
        partNrg[pb] = ((fMultDiv2(alpha1, slotNrg[pb]) << scaleCur) +
                       (fMultDiv2(alpha, partNrgPrev[pb]) >> scalePrev))
                      << 1;
        maxVal |= partNrg[pb];
        frameNrg += slotNrg[pb] >> 3;
      }
    } else { /* if ( (scaleCur >= 0) && (scalePrev < 0) ) */
      scalePrev = -scalePrev;
      for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
        partNrg[pb] = ((fMultDiv2(alpha1, slotNrg[pb]) >> scaleCur) +
                       (fMultDiv2(alpha, partNrgPrev[pb]) << scalePrev))
                      << 1;
        maxVal |= partNrg[pb];
        frameNrg += slotNrg[pb] >> 3;
      }
    }

    /* frameNrg /= (END_BB_ENV - START_BB_ENV); 0.88888888888f =
     * (1/(END_BB_ENV-START_BB_ENV)<<3; shift with 3 is compensated in loop
     * above */
    frameNrg = fMult(frameNrg, FL2FXCONST_DBL(0.88888888888f));

    /* store scalefactor and headroom for part nrg prev */
    pPartNrgPrevSF[0] = partNrgSF;
    pPartNrgPrev2SF[0] = fixMax(0, CntLeadingZeros(maxVal) - 1);

    commonScale = fixMax(frameNrgSF - SF_ALPHA1 + 1, pFrameNrgPrevSF[0] + 1);
    scalePrev = fixMin(commonScale - pFrameNrgPrevSF[0], DFRACT_BITS - 1);
    scaleCur = fixMin(commonScale - frameNrgSF + SF_ALPHA1, DFRACT_BITS - 1);
    frameNrgSF = commonScale;

    frameNrg = ((fMultDiv2(alpha1, frameNrg) >> scaleCur) +
                (fMultDiv2(alpha, pBBEnvState->frameNrgPrev__FDK[prevChOffs]) >>
                 scalePrev))
               << 1;

    clz = fixMax(0, CntLeadingZeros(frameNrg) - 1);
    pBBEnvState->frameNrgPrev__FDK[prevChOffs] = frameNrg << clz;
    pFrameNrgPrevSF[0] = frameNrgSF - clz;

    env = FL2FXCONST_DBL(0.0f);
    scale = clz + partNrgSF - frameNrgSF;
    scale_min = DFRACT_BITS - 1;
    for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
      if ((partNrg[pb] | slotNrg[pb]) != FL2FXCONST_DBL(0.0f)) {
        INT s;
        INT sc = 0;
        INT sn = fixMax(0, CntLeadingZeros(slotNrg[pb]) - 1);
        FIXP_DBL inv_sqrt = invSqrtNorm2(partNrg[pb], &sc);
        FIXP_DBL res = fMult(slotNrg[pb] << sn, fPow2(inv_sqrt));

        s = fixMax(0, CntLeadingZeros(res) - 1);
        res = res << s;

        sc = scale - (2 * sc - sn - s);
        scale_min = fixMin(scale_min, sc);

        resPb[pb] = res;
        resPbSF[pb] = sc;
      } else {
        resPb[pb] = (FIXP_DBL)0;
        resPbSF[pb] = 0;
      }
    }

    scale_min = 4 - scale_min;

    for (pb = START_BB_ENV; pb < END_BB_ENV; pb++) {
      INT sc = fixMax(fixMin(resPbSF[pb] + scale_min, DFRACT_BITS - 1),
                      -(DFRACT_BITS - 1));

      if (sc < 0) {
        env += resPb[pb] << (-sc);
      } else {
        env += resPb[pb] >> (sc);
      }
    }

    env = fMultDiv2(env, pBBEnvState->frameNrgPrev__FDK[prevChOffs]);
    envSF = slotNrgSF + scale_min + 1;

    commonScale = fixMax(envSF - SF_BETA1 + 1, pNormNrgPrevSF[0] + 1);
    scalePrev = fixMin(commonScale - pNormNrgPrevSF[0], DFRACT_BITS - 1);
    scaleCur = fixMin(commonScale - envSF + SF_BETA1, DFRACT_BITS - 1);

    normNrg = ((fMultDiv2(beta1, env) >> scaleCur) +
               (fMultDiv2(beta, pBBEnvState->normNrgPrev__FDK[prevChOffs]) >>
                scalePrev))
              << 1;

    clz = fixMax(0, CntLeadingZeros(normNrg) - 1);
    pBBEnvState->normNrgPrev__FDK[prevChOffs] = normNrg << clz;
    pNormNrgPrevSF[0] = commonScale - clz;

    if (shapeActiv) {
      if ((env | normNrg) != FL2FXCONST_DBL(0.0f)) {
        INT sc, se, sn;
        se = fixMax(0, CntLeadingZeros(env) - 1);
        sc = commonScale + SF_DIV32 - envSF + se;
        env = fMult(sqrtFixp((env << se) >> (sc & 0x1)),
                    invSqrtNorm2(normNrg, &sn));

        sc = fixMin((sc >> 1) - sn, DFRACT_BITS - 1);
        if (sc < 0) {
          env <<= (-sc);
        } else {
          env >>= (sc);
        }
      }
      /* env is scaled by SF_DIV32/2 bits */
    }
    pEnv[ch] = env;
  }

  C_ALLOC_SCRATCH_END(resPbSF, INT, (END_BB_ENV - START_BB_ENV));
  C_ALLOC_SCRATCH_END(resPb, FIXP_DBL, (END_BB_ENV - START_BB_ENV));
  C_ALLOC_SCRATCH_END(pScratchBuffer, FIXP_DBL, (2 * 42 + MAX_PARAMETER_BANDS));
}

void SpatialDecReshapeBBEnv(spatialDec *self, const SPATIAL_BS_FRAME *frame,
                            INT ts) {
  INT ch, scale;
  INT dryFacSF, slotAmpSF;
  INT slotAmp_dry_e, slotAmp_wet_e;
  FIXP_DBL tmp, dryFac, envShape;
  FIXP_DBL slotAmp_dry, slotAmp_wet, slotAmp_ratio;
  FIXP_DBL envDry[MAX_OUTPUT_CHANNELS], envDmx[2];

  INT cplxBands;
  INT hybBands = self->hybridBands - 6;

  cplxBands = self->hybridBands - 6;

  /* extract downmix envelope(s) */
  switch (self->treeConfig) {
    default:
      extractBBEnv(self, INP_DMX, 0, fMin(self->numInputChannels, 2), envDmx,
                   frame);
  }

  /* extract dry and wet envelopes */
  extractBBEnv(self, INP_DRY_WET, 0, self->numOutputChannels, envDry, frame);

  for (ch = 0; ch < self->numOutputChannels; ch++) {
    INT ch2;

    ch2 = row2channelGES[self->treeConfig][ch];

    if (ch2 == -1) continue;

    if (frame->tempShapeEnableChannelGES[ch2]) {
      INT sc;

      /* reshape dry and wet signals according to transmitted envelope */

      /* De-quantize GES data */
      FDK_ASSERT((frame->bsEnvShapeData[ch2][ts] >= 0) &&
                 (frame->bsEnvShapeData[ch2][ts] <= 4));
      FDK_ASSERT((self->envQuantMode == 0) || (self->envQuantMode == 1));
      envShape =
          FX_CFG2FX_DBL(envShapeDataTable__FDK[frame->bsEnvShapeData[ch2][ts]]
                                              [self->envQuantMode]);

      /* get downmix channel */
      ch2 = self->row2channelDmxGES[ch];

      /* multiply ratio with dmx envelope; tmp is scaled by SF_DIV32/2+SF_SHAPE
       * bits */
      if (ch2 == 2) {
        tmp = fMultDiv2(envShape, envDmx[0]) + fMultDiv2(envShape, envDmx[1]);
      } else {
        tmp = fMult(envShape, envDmx[ch2]);
      }

      /* weighting factors */
      dryFacSF = slotAmpSF = 0;
      dryFac = slotAmp_ratio = FL2FXCONST_DBL(0.0f);

      /* dryFac will be scaled by dryFacSF bits */
      if (envDry[ch] != FL2FXCONST_DBL(0.0f)) {
        envDry[ch] = invSqrtNorm2(envDry[ch], &dryFacSF);
        dryFac = fMultDiv2(tmp, fPow2Div2(envDry[ch])) << 2;
        dryFacSF = SF_SHAPE + 2 * dryFacSF;
      }

      slotAmp_dry_e = slotAmp_wet_e = 0;

      /* calculate slotAmp_dry and slotAmp_wet */
      slotAmp(&slotAmp_dry, &slotAmp_dry_e, &slotAmp_wet, &slotAmp_wet_e,
              &self->hybOutputRealDry__FDK[ch][6],
              &self->hybOutputImagDry__FDK[ch][6],
              &self->hybOutputRealWet__FDK[ch][6],
              &self->hybOutputImagWet__FDK[ch][6], cplxBands, hybBands);

      /* exponents must be even due to subsequent square root calculation */
      FDK_ASSERT(((slotAmp_dry_e & 1) == 0) && ((slotAmp_wet_e & 1) == 0));

      /* slotAmp_ratio will be scaled by slotAmpSF bits */
      if (slotAmp_dry != FL2FXCONST_DBL(0.0f)) {
        slotAmp_wet = sqrtFixp(slotAmp_wet);
        slotAmp_dry = invSqrtNorm2(slotAmp_dry, &slotAmpSF);

        slotAmp_ratio = fMult(slotAmp_wet, slotAmp_dry);
        slotAmpSF = slotAmpSF + (slotAmp_wet_e >> 1) - (slotAmp_dry_e >> 1);
      }

      /* calculate common scale factor */
      scale =
          fixMax(3, fixMax(dryFacSF, slotAmpSF)); /* scale is at least with 3
                                                     bits to avoid overflows
                                                     when calculating dryFac  */
      dryFac = dryFac >> fixMin(scale - dryFacSF, DFRACT_BITS - 1);
      slotAmp_ratio =
          slotAmp_ratio >> fixMin(scale - slotAmpSF, DFRACT_BITS - 1);

      /* limit dryFac */
      dryFac = fixMax(
          FL2FXCONST_DBL(0.25f) >> (INT)fixMin(2 * scale, DFRACT_BITS - 1),
          fMult(dryFac, slotAmp_ratio) -
              (slotAmp_ratio >> fixMin(scale, DFRACT_BITS - 1)) +
              (dryFac >> fixMin(scale, DFRACT_BITS - 1)));
      dryFac = fixMin(
          FL2FXCONST_DBL(0.50f) >> (INT)fixMin(2 * scale - 3, DFRACT_BITS - 1),
          dryFac); /* reduce shift bits by 3, because upper
                      limit 4.0 is scaled with 3 bits */
      scale = 2 * scale + 1;

      /* improve precision for dryFac */
      sc = fixMax(0, CntLeadingZeros(dryFac) - 1);
      dryFac = dryFac << (INT)fixMin(scale, sc);
      scale = scale - fixMin(scale, sc);

      /* shaping */
      shapeBBEnv(&self->hybOutputRealDry__FDK[ch][6],
                 &self->hybOutputImagDry__FDK[ch][6], dryFac,
                 fixMin(scale, DFRACT_BITS - 1), cplxBands, hybBands);
    }
  }
}