path: root/fdk-aac/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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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
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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
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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.

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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
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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 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;
}