path: root/libSACdec/src/sac_calcM1andM2.cpp

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

© Copyright  1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
Forschung e.V. All rights reserved.

 1.    INTRODUCTION
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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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Patent licenses for necessary patent claims for the FDK AAC Codec (including
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Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
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----------------------------------------------------------------------------- */

/*********************** MPEG surround decoder library *************************

   Author(s):

   Description: SAC Dec M1 and M2 calculation

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

#include "sac_calcM1andM2.h"
#include "sac_bitdec.h"
#include "sac_process.h"
#include "sac_rom.h"
#include "sac_smoothing.h"
#include "FDK_trigFcts.h"

/* assorted definitions and constants */

#define ABS_THR2 1.0e-9
#define SQRT2_FDK \
  ((FIXP_DBL)FL2FXCONST_DBL(0.70710678118f)) /* FDKsqrt(2.0) scaled by 0.5 */

static void param2UMX_PS__FDK(spatialDec* self,
                              FIXP_DBL H11[MAX_PARAMETER_BANDS],
                              FIXP_DBL H12[MAX_PARAMETER_BANDS],
                              FIXP_DBL H21[MAX_PARAMETER_BANDS],
                              FIXP_DBL H22[MAX_PARAMETER_BANDS],
                              FIXP_DBL c_l[MAX_PARAMETER_BANDS],
                              FIXP_DBL c_r[MAX_PARAMETER_BANDS], int ottBoxIndx,
                              int parameterSetIndx, int resBands);

static void param2UMX_PS_Core__FDK(
    const SCHAR cld[MAX_PARAMETER_BANDS], const SCHAR icc[MAX_PARAMETER_BANDS],
    const int numOttBands, const int resBands,
    FIXP_DBL H11[MAX_PARAMETER_BANDS], FIXP_DBL H12[MAX_PARAMETER_BANDS],
    FIXP_DBL H21[MAX_PARAMETER_BANDS], FIXP_DBL H22[MAX_PARAMETER_BANDS],
    FIXP_DBL c_l[MAX_PARAMETER_BANDS], FIXP_DBL c_r[MAX_PARAMETER_BANDS]);

static void param2UMX_PS_IPD_OPD__FDK(
    spatialDec* self, const SPATIAL_BS_FRAME* frame,
    FIXP_DBL H11re[MAX_PARAMETER_BANDS], FIXP_DBL H12re[MAX_PARAMETER_BANDS],
    FIXP_DBL H21re[MAX_PARAMETER_BANDS], FIXP_DBL H22re[MAX_PARAMETER_BANDS],
    FIXP_DBL c_l[MAX_PARAMETER_BANDS], FIXP_DBL c_r[MAX_PARAMETER_BANDS],
    int ottBoxIndx, int parameterSetIndx, int residualBands);

static void param2UMX_Prediction__FDK(
    spatialDec* self, FIXP_DBL H11re[MAX_PARAMETER_BANDS],
    FIXP_DBL H11im[MAX_PARAMETER_BANDS], FIXP_DBL H12re[MAX_PARAMETER_BANDS],
    FIXP_DBL H12im[MAX_PARAMETER_BANDS], FIXP_DBL H21re[MAX_PARAMETER_BANDS],
    FIXP_DBL H21im[MAX_PARAMETER_BANDS], FIXP_DBL H22re[MAX_PARAMETER_BANDS],
    FIXP_DBL H22im[MAX_PARAMETER_BANDS], int ottBoxIndx, int parameterSetIndx,
    int resBands);

/* static void SpatialDecCalculateM0(spatialDec* self,int ps); */
static SACDEC_ERROR SpatialDecCalculateM1andM2_212(
    spatialDec* self, int ps, const SPATIAL_BS_FRAME* frame);

/*******************************************************************************
 Functionname: SpatialDecGetResidualIndex
 *******************************************************************************

 Description:

 Arguments:

 Input:

 Output:

*******************************************************************************/
int SpatialDecGetResidualIndex(spatialDec* self, int row) {
  return row2residual[self->treeConfig][row];
}

/*******************************************************************************
 Functionname: UpdateAlpha
 *******************************************************************************

 Description:

 Arguments:

 Input:

 Output:

*******************************************************************************/
static void updateAlpha(spatialDec* self) {
  int nChIn = self->numInputChannels;
  int ch;

  for (ch = 0; ch < nChIn; ch++) {
    FIXP_DBL alpha = /* FL2FXCONST_DBL(1.0f) */ (FIXP_DBL)MAXVAL_DBL;

    self->arbdmxAlphaPrev__FDK[ch] = self->arbdmxAlpha__FDK[ch];

    self->arbdmxAlpha__FDK[ch] = alpha;
  }
}

/*******************************************************************************
 Functionname: SpatialDecCalculateM1andM2
 *******************************************************************************
 Description:
 Arguments:
*******************************************************************************/
SACDEC_ERROR SpatialDecCalculateM1andM2(spatialDec* self, int ps,
                                        const SPATIAL_BS_FRAME* frame) {
  SACDEC_ERROR err = MPS_OK;

  if ((self->arbitraryDownmix != 0) && (ps == 0)) {
    updateAlpha(self);
  }

  self->pActivM2ParamBands = NULL;

  switch (self->upmixType) {
    case UPMIXTYPE_BYPASS:
    case UPMIXTYPE_NORMAL:
      switch (self->treeConfig) {
        case TREE_212:
          err = SpatialDecCalculateM1andM2_212(self, ps, frame);
          break;
        default:
          err = MPS_WRONG_TREECONFIG;
      };
      break;

    default:
      err = MPS_WRONG_TREECONFIG;
  }

  if (err != MPS_OK) {
    goto bail;
  }

bail:
  return err;
}

/*******************************************************************************
 Functionname: SpatialDecCalculateM1andM2_212
 *******************************************************************************

 Description:

 Arguments:

 Return:

*******************************************************************************/
static SACDEC_ERROR SpatialDecCalculateM1andM2_212(
    spatialDec* self, int ps, const SPATIAL_BS_FRAME* frame) {
  SACDEC_ERROR err = MPS_OK;
  int pb;

  FIXP_DBL H11re[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};
  FIXP_DBL H12re[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};
  FIXP_DBL H21re[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};
  FIXP_DBL H22re[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};
  FIXP_DBL H11im[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};
  FIXP_DBL H21im[MAX_PARAMETER_BANDS] = {FL2FXCONST_DBL(0.0f)};

  INT phaseCoding = self->phaseCoding;

  switch (phaseCoding) {
    case 1:
      /* phase coding: yes; residuals: no */
      param2UMX_PS_IPD_OPD__FDK(self, frame, H11re, H12re, H21re, H22re, NULL,
                                NULL, 0, ps, self->residualBands[0]);
      break;
    case 3:
      /* phase coding: yes; residuals: yes */
      param2UMX_Prediction__FDK(self, H11re, H11im, H12re, NULL, H21re, H21im,
                                H22re, NULL, 0, ps, self->residualBands[0]);
      break;
    default:
      if (self->residualCoding) {
        /* phase coding: no; residuals: yes */
        param2UMX_Prediction__FDK(self, H11re, NULL, H12re, NULL, H21re, NULL,
                                  H22re, NULL, 0, ps, self->residualBands[0]);
      } else {
        /* phase coding: no; residuals: no */
        param2UMX_PS__FDK(self, H11re, H12re, H21re, H22re, NULL, NULL, 0, ps,
                          0);
      }
      break;
  }

  for (pb = 0; pb < self->numParameterBands; pb++) {
    self->M2Real__FDK[0][0][pb] = (H11re[pb]);
    self->M2Real__FDK[0][1][pb] = (H12re[pb]);

    self->M2Real__FDK[1][0][pb] = (H21re[pb]);
    self->M2Real__FDK[1][1][pb] = (H22re[pb]);
  }
  if (phaseCoding == 3) {
    for (pb = 0; pb < self->numParameterBands; pb++) {
      self->M2Imag__FDK[0][0][pb] = (H11im[pb]);
      self->M2Imag__FDK[1][0][pb] = (H21im[pb]);
      self->M2Imag__FDK[0][1][pb] = (FIXP_DBL)0;  // H12im[pb];
      self->M2Imag__FDK[1][1][pb] = (FIXP_DBL)0;  // H22im[pb];
    }
  }

  if (self->phaseCoding == 1) {
    SpatialDecSmoothOPD(
        self, frame,
        ps); /* INPUT: PhaseLeft, PhaseRight, (opdLeftState, opdRightState) */
  }

  return err;
}

/*******************************************************************************
 Functionname: param2UMX_PS_Core
 *******************************************************************************

 Description:

 Arguments:

 Return:

*******************************************************************************/
static void param2UMX_PS_Core__FDK(
    const SCHAR cld[MAX_PARAMETER_BANDS], const SCHAR icc[MAX_PARAMETER_BANDS],
    const int numOttBands, const int resBands,
    FIXP_DBL H11[MAX_PARAMETER_BANDS], FIXP_DBL H12[MAX_PARAMETER_BANDS],
    FIXP_DBL H21[MAX_PARAMETER_BANDS], FIXP_DBL H22[MAX_PARAMETER_BANDS],
    FIXP_DBL c_l[MAX_PARAMETER_BANDS], FIXP_DBL c_r[MAX_PARAMETER_BANDS]) {
  int band;

  if ((c_l != NULL) && (c_r != NULL)) {
    for (band = 0; band < numOttBands; band++) {
      SpatialDequantGetCLDValues(cld[band], &c_l[band], &c_r[band]);
    }
  }

  band = 0;
  FDK_ASSERT(resBands == 0);
  for (; band < numOttBands; band++) {
    /* compute mixing variables: */
    const int idx1 = cld[band];
    const int idx2 = icc[band];
    H11[band] = FX_CFG2FX_DBL(H11_nc[idx1][idx2]);
    H21[band] = FX_CFG2FX_DBL(H11_nc[30 - idx1][idx2]);
    H12[band] = FX_CFG2FX_DBL(H12_nc[idx1][idx2]);
    H22[band] = FX_CFG2FX_DBL(-H12_nc[30 - idx1][idx2]);
  }
}

/*******************************************************************************
 Functionname: param2UMX_PS
 *******************************************************************************

 Description:

 Arguments:

 Return:

*******************************************************************************/
static void param2UMX_PS__FDK(spatialDec* self,
                              FIXP_DBL H11[MAX_PARAMETER_BANDS],
                              FIXP_DBL H12[MAX_PARAMETER_BANDS],
                              FIXP_DBL H21[MAX_PARAMETER_BANDS],
                              FIXP_DBL H22[MAX_PARAMETER_BANDS],
                              FIXP_DBL c_l[MAX_PARAMETER_BANDS],
                              FIXP_DBL c_r[MAX_PARAMETER_BANDS], int ottBoxIndx,
                              int parameterSetIndx, int residualBands) {
  int band;
  param2UMX_PS_Core__FDK(self->ottCLD__FDK[ottBoxIndx][parameterSetIndx],
                         self->ottICC__FDK[ottBoxIndx][parameterSetIndx],
                         self->numOttBands[ottBoxIndx], residualBands, H11, H12,
                         H21, H22, c_l, c_r);

  for (band = self->numOttBands[ottBoxIndx]; band < self->numParameterBands;
       band++) {
    H11[band] = H21[band] = H12[band] = H22[band] = FL2FXCONST_DBL(0.f);
  }
}

#define N_CLD (31)
#define N_IPD (16)

static const FIXP_DBL sinIpd_tab[N_IPD] = {
    FIXP_DBL(0x00000000), FIXP_DBL(0x30fbc54e), FIXP_DBL(0x5a827999),
    FIXP_DBL(0x7641af3d), FIXP_DBL(0x7fffffff), FIXP_DBL(0x7641af3d),
    FIXP_DBL(0x5a82799a), FIXP_DBL(0x30fbc54d), FIXP_DBL(0xffffffff),
    FIXP_DBL(0xcf043ab3), FIXP_DBL(0xa57d8666), FIXP_DBL(0x89be50c3),
    FIXP_DBL(0x80000000), FIXP_DBL(0x89be50c3), FIXP_DBL(0xa57d8666),
    FIXP_DBL(0xcf043ab2),
};

/* cosIpd[i] = sinIpd[(i+4)&15] */
#define SIN_IPD(a) (sinIpd_tab[(a)])
#define COS_IPD(a) (sinIpd_tab[((a) + 4) & 15])  //(cosIpd_tab[(a)])

static const FIXP_SGL sqrt_one_minus_ICC2[8] = {
    FL2FXCONST_SGL(0.0f),
    FL2FXCONST_SGL(0.349329357483736f),
    FL2FXCONST_SGL(0.540755219669676f),
    FL2FXCONST_SGL(0.799309172723546f),
    FL2FXCONST_SGL(0.929968187843004f),
    FX_DBL2FXCONST_SGL(MAXVAL_DBL),
    FL2FXCONST_SGL(0.80813303360276f),
    FL2FXCONST_SGL(0.141067359796659f),
};

/* exponent of sqrt(CLD) */
static const SCHAR sqrt_CLD_e[N_CLD] = {
    -24, -7, -6, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 1,
    1,   1,  1,  2,  2,  3,  3,  4,  4,  5,  5,  6,  7, 8, 25};

static const FIXP_DBL sqrt_CLD_m[N_CLD] = {
    FL2FXCONST_DBL(0.530542153566195f),
    FL2FXCONST_DBL(0.719796896243647f),
    FL2FXCONST_DBL(0.64f),
    FL2FXCONST_DBL(0.569049411212455f),
    FL2FXCONST_DBL(0.505964425626941f),
    FL2FXCONST_DBL(0.899746120304559f),
    FL2FXCONST_DBL(0.635462587779425f),
    FL2FXCONST_DBL(0.897614763441571f),
    FL2FXCONST_DBL(0.633957276984445f),
    FL2FXCONST_DBL(0.895488455427336f),
    FL2FXCONST_DBL(0.632455532033676f),
    FL2FXCONST_DBL(0.796214341106995f),
    FL2FXCONST_DBL(0.501187233627272f),
    FL2FXCONST_DBL(0.630957344480193f),
    FL2FXCONST_DBL(0.794328234724281f),
    FL2FXCONST_DBL(0.5f),
    FL2FXCONST_DBL(0.629462705897084f),
    FL2FXCONST_DBL(0.792446596230557f),
    FL2FXCONST_DBL(0.99763115748444f),
    FL2FXCONST_DBL(0.627971607877395f),
    FL2FXCONST_DBL(0.790569415042095f),
    FL2FXCONST_DBL(0.558354490188704f),
    FL2FXCONST_DBL(0.788696680600242f),
    FL2FXCONST_DBL(0.557031836333591f),
    FL2FXCONST_DBL(0.786828382371355f),
    FL2FXCONST_DBL(0.555712315637163f),
    FL2FXCONST_DBL(0.988211768802619f),
    FL2FXCONST_DBL(0.87865832060992f),
    FL2FXCONST_DBL(0.78125f),
    FL2FXCONST_DBL(0.694640394546454f),
    FL2FXCONST_DBL(0.942432183077448f),
};

static const FIXP_DBL CLD_m[N_CLD] = {
    FL2FXCONST_DBL(0.281474976710656f),
    FL2FXCONST_DBL(0.518107571841987f),
    FL2FXCONST_DBL(0.4096f),
    FL2FXCONST_DBL(0.323817232401242f),
    FL2FXCONST_DBL(0.256f),
    FL2FXCONST_DBL(0.809543081003105f),
    FL2FXCONST_DBL(0.403812700467324f),
    FL2FXCONST_DBL(0.805712263548267f),
    FL2FXCONST_DBL(0.401901829041533f),
    FL2FXCONST_DBL(0.801899573803636f),
    FL2FXCONST_DBL(0.4f),
    FL2FXCONST_DBL(0.633957276984445f),
    FL2FXCONST_DBL(0.251188643150958f),
    FL2FXCONST_DBL(0.398107170553497f),
    FL2FXCONST_DBL(0.630957344480193f),
    FL2FXCONST_DBL(0.25f),
    FL2FXCONST_DBL(0.396223298115278f),
    FL2FXCONST_DBL(0.627971607877395f),
    FL2FXCONST_DBL(0.995267926383743f),
    FL2FXCONST_DBL(0.394348340300121f),
    FL2FXCONST_DBL(0.625f),
    FL2FXCONST_DBL(0.311759736713887f),
    FL2FXCONST_DBL(0.62204245398984f),
    FL2FXCONST_DBL(0.310284466689172f),
    FL2FXCONST_DBL(0.619098903305123f),
    FL2FXCONST_DBL(0.308816177750818f),
    FL2FXCONST_DBL(0.9765625f),
    FL2FXCONST_DBL(0.772040444377046f),
    FL2FXCONST_DBL(0.6103515625f),
    FL2FXCONST_DBL(0.482525277735654f),
    FL2FXCONST_DBL(0.888178419700125),
};

static FIXP_DBL dequantIPD_CLD_ICC_splitAngle__FDK_Function(INT ipdIdx,
                                                            INT cldIdx,
                                                            INT iccIdx) {
  FIXP_DBL cld;
  SpatialDequantGetCLD2Values(cldIdx, &cld);

  /*const FIXP_DBL one_m = (FIXP_DBL)MAXVAL_DBL;
  const int one_e = 0;*/
  const FIXP_DBL one_m = FL2FXCONST_DBL(0.5f);
  const int one_e = 1;
  /* iidLin = sqrt(cld); */
  FIXP_DBL iidLin_m = sqrt_CLD_m[cldIdx];
  int iidLin_e = sqrt_CLD_e[cldIdx];
  /* iidLin2 = cld; */
  FIXP_DBL iidLin2_m = CLD_m[cldIdx];
  int iidLin2_e = sqrt_CLD_e[cldIdx] << 1;
  /* iidLin21 = iidLin2 + 1.0f; */
  int iidLin21_e;
  FIXP_DBL iidLin21_m =
      fAddNorm(iidLin2_m, iidLin2_e, one_m, one_e, &iidLin21_e);
  /* iidIcc2 = iidLin * icc * 2.0f; */
  FIXP_CFG icc = dequantICC__FDK[iccIdx];
  FIXP_DBL temp1_m, temp1c_m;
  int temp1_e, temp1c_e;
  temp1_m = fMult(iidLin_m, icc);
  temp1_e = iidLin_e + 1;

  FIXP_DBL cosIpd, sinIpd;
  cosIpd = COS_IPD(ipdIdx);
  sinIpd = SIN_IPD(ipdIdx);

  temp1c_m = fMult(temp1_m, cosIpd);
  temp1c_e = temp1_e;  //+cosIpd_e;

  int temp2_e, temp3_e, inv_temp3_e, ratio_e;
  FIXP_DBL temp2_m =
      fAddNorm(iidLin21_m, iidLin21_e, temp1c_m, temp1c_e, &temp2_e);
  FIXP_DBL temp3_m =
      fAddNorm(iidLin21_m, iidLin21_e, temp1_m, temp1_e, &temp3_e);
  /* calculate 1/temp3 needed later */
  inv_temp3_e = temp3_e;
  FIXP_DBL inv_temp3_m = invFixp(temp3_m, &inv_temp3_e);
  FIXP_DBL ratio_m =
      fAddNorm(fMult(inv_temp3_m, temp2_m), (inv_temp3_e + temp2_e),
               FL2FXCONST_DBL(1e-9f), 0, &ratio_e);

  int weight2_e, tempb_atan2_e;
  FIXP_DBL weight2_m =
      fPow(ratio_m, ratio_e, FL2FXCONST_DBL(0.5f), -1, &weight2_e);
  /* atan2(w2*sinIpd, w1*iidLin + w2*cosIpd) = atan2(w2*sinIpd, (2 - w2)*iidLin
   * + w2*cosIpd) = atan2(w2*sinIpd, 2*iidLin + w2*(cosIpd - iidLin)); */
  /* tmpa_atan2 = w2*sinIpd; tmpb_atan2 = 2*iidLin + w2*(cosIpd - iidLin); */
  FIXP_DBL tempb_atan2_m = iidLin_m;
  tempb_atan2_e = iidLin_e + 1;
  int add_tmp1_e = 0;
  FIXP_DBL add_tmp1_m = fAddNorm(cosIpd, 0, -iidLin_m, iidLin_e, &add_tmp1_e);
  FIXP_DBL add_tmp2_m = fMult(add_tmp1_m, weight2_m);
  int add_tmp2_e = add_tmp1_e + weight2_e;
  tempb_atan2_m = fAddNorm(tempb_atan2_m, tempb_atan2_e, add_tmp2_m, add_tmp2_e,
                           &tempb_atan2_e);

  FIXP_DBL tempa_atan2_m = fMult(weight2_m, sinIpd);
  int tempa_atan2_e = weight2_e;  // + sinIpd_e;

  if (tempa_atan2_e > tempb_atan2_e) {
    tempb_atan2_m = (tempb_atan2_m >> (tempa_atan2_e - tempb_atan2_e));
    tempb_atan2_e = tempa_atan2_e;
  } else if (tempb_atan2_e > tempa_atan2_e) {
    tempa_atan2_m = (tempa_atan2_m >> (tempb_atan2_e - tempa_atan2_e));
  }

  return fixp_atan2(tempa_atan2_m, tempb_atan2_m);
}

static void calculateOpd(spatialDec* self, INT ottBoxIndx, INT parameterSetIndx,
                         FIXP_DBL opd[MAX_PARAMETER_BANDS]) {
  INT band;

  for (band = 0; band < self->numOttBandsIPD; band++) {
    INT idxCld = self->ottCLD__FDK[ottBoxIndx][parameterSetIndx][band];
    INT idxIpd = self->ottIPD__FDK[ottBoxIndx][parameterSetIndx][band];
    INT idxIcc = self->ottICC__FDK[ottBoxIndx][parameterSetIndx][band];
    FIXP_DBL cld, ipd;

    ipd = FX_CFG2FX_DBL(dequantIPD__FDK[idxIpd]);

    SpatialDequantGetCLD2Values(idxCld, &cld);

    /* ipd(idxIpd==8) == PI */
    if ((cld == FL2FXCONST_DBL(0.0f)) && (idxIpd == 8)) {
      opd[2 * band] = FL2FXCONST_DBL(0.0f);
    } else {
      opd[2 * band] = (dequantIPD_CLD_ICC_splitAngle__FDK_Function(
                           idxIpd, idxCld, idxIcc) >>
                       (IPD_SCALE - AT2O_SF));
    }
    opd[2 * band + 1] = opd[2 * band] - ipd;
  }
}

/* wrap phase in rad to the range of 0 <= x < 2*pi */
static FIXP_DBL wrapPhase(FIXP_DBL phase) {
  while (phase < (FIXP_DBL)0) phase += PIx2__IPD;
  while (phase >= PIx2__IPD) phase -= PIx2__IPD;
  FDK_ASSERT((phase >= (FIXP_DBL)0) && (phase < PIx2__IPD));

  return phase;
}

/*******************************************************************************
 Functionname: param2UMX_PS_IPD
 *******************************************************************************

 Description:

 Arguments:

 Return:

*******************************************************************************/
static void param2UMX_PS_IPD_OPD__FDK(
    spatialDec* self, const SPATIAL_BS_FRAME* frame,
    FIXP_DBL H11[MAX_PARAMETER_BANDS], FIXP_DBL H12[MAX_PARAMETER_BANDS],
    FIXP_DBL H21[MAX_PARAMETER_BANDS], FIXP_DBL H22[MAX_PARAMETER_BANDS],
    FIXP_DBL c_l[MAX_PARAMETER_BANDS], FIXP_DBL c_r[MAX_PARAMETER_BANDS],
    int ottBoxIndx, int parameterSetIndx, int residualBands) {
  INT band;
  FIXP_DBL opd[2 * MAX_PARAMETER_BANDS];
  INT numOttBands = self->numOttBands[ottBoxIndx];
  INT numIpdBands;

  numIpdBands = frame->phaseMode ? self->numOttBandsIPD : 0;

  FDK_ASSERT(self->residualCoding == 0);

  param2UMX_PS_Core__FDK(self->ottCLD__FDK[ottBoxIndx][parameterSetIndx],
                         self->ottICC__FDK[ottBoxIndx][parameterSetIndx],
                         self->numOttBands[ottBoxIndx], residualBands, H11, H12,
                         H21, H22, c_l, c_r);

  for (band = self->numOttBands[ottBoxIndx]; band < self->numParameterBands;
       band++) {
    H11[band] = H21[band] = H12[band] = H22[band] = FL2FXCONST_DBL(0.f);
  }

  if (frame->phaseMode) {
    calculateOpd(self, ottBoxIndx, parameterSetIndx, opd);

    for (band = 0; band < numIpdBands; band++) {
      self->PhaseLeft__FDK[band] = wrapPhase(opd[2 * band]);
      self->PhaseRight__FDK[band] = wrapPhase(opd[2 * band + 1]);
    }
  }

  for (band = numIpdBands; band < numOttBands; band++) {
    self->PhaseLeft__FDK[band] = FL2FXCONST_DBL(0.0f);
    self->PhaseRight__FDK[band] = FL2FXCONST_DBL(0.0f);
  }
}

FDK_INLINE void param2UMX_Prediction_Core__FDK(
    FIXP_DBL* H11re, FIXP_DBL* H11im, FIXP_DBL* H12re, FIXP_DBL* H12im,
    FIXP_DBL* H21re, FIXP_DBL* H21im, FIXP_DBL* H22re, FIXP_DBL* H22im,
    int cldIdx, int iccIdx, int ipdIdx, int band, int numOttBandsIPD,
    int resBands) {
#define MAX_WEIGHT (1.2f)
  FDK_ASSERT((H12im == NULL) && (H22im == NULL)); /* always == 0 */

  if ((band < numOttBandsIPD) && (cldIdx == 15) && (iccIdx == 0) &&
      (ipdIdx == 8)) {
    const FIXP_DBL gain =
        FL2FXCONST_DBL(0.5f / MAX_WEIGHT) >> SCALE_PARAM_M2_212_PRED;

    *H11re = gain;
    if (band < resBands) {
      *H21re = gain;
      *H12re = gain;
      *H22re = -gain;
    } else {
      *H21re = -gain;
      *H12re = (FIXP_DBL)0;
      *H22re = (FIXP_DBL)0;
    }
    if ((H11im != NULL) &&
        (H21im != NULL) /*&& (H12im!=NULL) && (H22im!=NULL)*/) {
      *H11im = (FIXP_DBL)0;
      *H21im = (FIXP_DBL)0;
      /* *H12im = (FIXP_DBL)0; */
      /* *H22im = (FIXP_DBL)0; */
    }
  } else {
    const FIXP_DBL one_m = (FIXP_DBL)MAXVAL_DBL;
    const int one_e = 0;
    /* iidLin = sqrt(cld); */
    FIXP_DBL iidLin_m = sqrt_CLD_m[cldIdx];
    int iidLin_e = sqrt_CLD_e[cldIdx];
    /* iidLin2 = cld; */
    FIXP_DBL iidLin2_m = CLD_m[cldIdx];
    int iidLin2_e = sqrt_CLD_e[cldIdx] << 1;
    /* iidLin21 = iidLin2 + 1.0f; */
    int iidLin21_e;
    FIXP_DBL iidLin21_m =
        fAddNorm(iidLin2_m, iidLin2_e, one_m, one_e, &iidLin21_e);
    /* iidIcc2 = iidLin * icc * 2.0f; */
    FIXP_CFG icc = dequantICC__FDK[iccIdx];
    int iidIcc2_e = iidLin_e + 1;
    FIXP_DBL iidIcc2_m = fMult(iidLin_m, icc);
    FIXP_DBL temp_m, sqrt_temp_m, inv_temp_m, weight_m;
    int temp_e, sqrt_temp_e, inv_temp_e, weight_e, scale;
    FIXP_DBL cosIpd, sinIpd;

    cosIpd = COS_IPD((band < numOttBandsIPD) ? ipdIdx : 0);
    sinIpd = SIN_IPD((band < numOttBandsIPD) ? ipdIdx : 0);

    /* temp    = iidLin21 + iidIcc2 * cosIpd; */
    temp_m = fAddNorm(iidLin21_m, iidLin21_e, fMult(iidIcc2_m, cosIpd),
                      iidIcc2_e, &temp_e);

    /* calculate 1/temp needed later */
    inv_temp_e = temp_e;
    inv_temp_m = invFixp(temp_m, &inv_temp_e);

    /* 1/weight = sqrt(temp) * 1/sqrt(iidLin21) */
    if (temp_e & 1) {
      sqrt_temp_m = temp_m >> 1;
      sqrt_temp_e = (temp_e + 1) >> 1;
    } else {
      sqrt_temp_m = temp_m;
      sqrt_temp_e = temp_e >> 1;
    }
    sqrt_temp_m = sqrtFixp(sqrt_temp_m);
    if (iidLin21_e & 1) {
      iidLin21_e += 1;
      iidLin21_m >>= 1;
    }
    /* weight_[m,e] is actually 1/weight in the next few lines */
    weight_m = invSqrtNorm2(iidLin21_m, &weight_e);
    weight_e -= iidLin21_e >> 1;
    weight_m = fMult(sqrt_temp_m, weight_m);
    weight_e += sqrt_temp_e;
    scale = fNorm(weight_m);
    weight_m = scaleValue(weight_m, scale);
    weight_e -= scale;
    /* weight = 0.5 * max(1/weight, 1/maxWeight) */
    if ((weight_e < 0) ||
        ((weight_e == 0) && (weight_m < FL2FXCONST_DBL(1.f / MAX_WEIGHT)))) {
      weight_m = FL2FXCONST_DBL(1.f / MAX_WEIGHT);
      weight_e = 0;
    }
    weight_e -= 1;

    {
      FIXP_DBL alphaRe_m, alphaIm_m, accu_m;
      int alphaRe_e, alphaIm_e, accu_e;
      /* alphaRe = (1.0f - iidLin2) / temp; */
      alphaRe_m = fAddNorm(one_m, one_e, -iidLin2_m, iidLin2_e, &alphaRe_e);
      alphaRe_m = fMult(alphaRe_m, inv_temp_m);
      alphaRe_e += inv_temp_e;

      /* H11re = weight - alphaRe * weight; */
      /* H21re = weight + alphaRe * weight; */
      accu_m = fMult(alphaRe_m, weight_m);
      accu_e = alphaRe_e + weight_e;
      {
        int accu2_e;
        FIXP_DBL accu2_m;
        accu2_m = fAddNorm(weight_m, weight_e, -accu_m, accu_e, &accu2_e);
        *H11re = scaleValue(accu2_m, accu2_e - SCALE_PARAM_M2_212_PRED);
        accu2_m = fAddNorm(weight_m, weight_e, accu_m, accu_e, &accu2_e);
        *H21re = scaleValue(accu2_m, accu2_e - SCALE_PARAM_M2_212_PRED);
      }

      if ((H11im != NULL) &&
          (H21im != NULL) /*&& (H12im != NULL) && (H22im != NULL)*/) {
        /* alphaIm = -iidIcc2 * sinIpd / temp; */
        alphaIm_m = fMult(-iidIcc2_m, sinIpd);
        alphaIm_m = fMult(alphaIm_m, inv_temp_m);
        alphaIm_e = iidIcc2_e + inv_temp_e;
        /* H11im = -alphaIm * weight; */
        /* H21im =  alphaIm * weight; */
        accu_m = fMult(alphaIm_m, weight_m);
        accu_e = alphaIm_e + weight_e;
        accu_m = scaleValue(accu_m, accu_e - SCALE_PARAM_M2_212_PRED);
        *H11im = -accu_m;
        *H21im = accu_m;

        /* *H12im = (FIXP_DBL)0; */
        /* *H22im = (FIXP_DBL)0; */
      }
    }
    if (band < resBands) {
      FIXP_DBL weight =
          scaleValue(weight_m, weight_e - SCALE_PARAM_M2_212_PRED);
      *H12re = weight;
      *H22re = -weight;
    } else {
      /* beta = 2.0f * iidLin * (float) sqrt(1.0f - icc * icc) * weight / temp;
       */
      FIXP_DBL beta_m;
      int beta_e;
      beta_m = FX_SGL2FX_DBL(sqrt_one_minus_ICC2[iccIdx]);
      beta_e = 1; /* multipication with 2.0f */
      beta_m = fMult(beta_m, weight_m);
      beta_e += weight_e;
      beta_m = fMult(beta_m, iidLin_m);
      beta_e += iidLin_e;
      beta_m = fMult(beta_m, inv_temp_m);
      beta_e += inv_temp_e;

      beta_m = scaleValue(beta_m, beta_e - SCALE_PARAM_M2_212_PRED);
      *H12re = beta_m;
      *H22re = -beta_m;
    }
  }
}

static void param2UMX_Prediction__FDK(spatialDec* self, FIXP_DBL* H11re,
                                      FIXP_DBL* H11im, FIXP_DBL* H12re,
                                      FIXP_DBL* H12im, FIXP_DBL* H21re,
                                      FIXP_DBL* H21im, FIXP_DBL* H22re,
                                      FIXP_DBL* H22im, int ottBoxIndx,
                                      int parameterSetIndx, int resBands) {
  int band;
  FDK_ASSERT((H12im == NULL) && (H22im == NULL)); /* always == 0 */

  for (band = 0; band < self->numParameterBands; band++) {
    int cldIdx = self->ottCLD__FDK[ottBoxIndx][parameterSetIndx][band];
    int iccIdx = self->ottICC__FDK[ottBoxIndx][parameterSetIndx][band];
    int ipdIdx = self->ottIPD__FDK[ottBoxIndx][parameterSetIndx][band];

    param2UMX_Prediction_Core__FDK(
        &H11re[band], (H11im ? &H11im[band] : NULL), &H12re[band], NULL,
        &H21re[band], (H21im ? &H21im[band] : NULL), &H22re[band], NULL, cldIdx,
        iccIdx, ipdIdx, band, self->numOttBandsIPD, resBands);
  }
}

/*******************************************************************************
 Functionname:  initM1andM2
 *******************************************************************************

 Description:

 Arguments:

 Return:

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

SACDEC_ERROR initM1andM2(spatialDec* self, int initStatesFlag,
                         int configChanged) {
  SACDEC_ERROR err = MPS_OK;

  self->bOverwriteM1M2prev = (configChanged && !initStatesFlag) ? 1 : 0;

  { self->numM2rows = self->numOutputChannels; }

  if (initStatesFlag) {
    int i, j, k;

    for (i = 0; i < self->numM2rows; i++) {
      for (j = 0; j < self->numVChannels; j++) {
        for (k = 0; k < MAX_PARAMETER_BANDS; k++) {
          self->M2Real__FDK[i][j][k] = FL2FXCONST_DBL(0);
          self->M2RealPrev__FDK[i][j][k] = FL2FXCONST_DBL(0);
        }
      }
    }
  }

  return err;
}