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

Software License for The Fraunhofer FDK AAC Codec Library for Android

© Copyright  1995 - 2020 Fraunhofer-Gesellschaft zur Förderung der angewandten

Forschung e.V. All rights reserved.

 1.    INTRODUCTION

The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software

that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding

scheme for digital audio. This FDK AAC Codec software is intended to be used on

a wide variety of Android devices.

AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient

general perceptual audio codecs. AAC-ELD is considered the best-performing

full-bandwidth communications codec by independent studies and is widely

deployed. AAC has been standardized by ISO and IEC as part of the MPEG

specifications.

Patent licenses for necessary patent claims for the FDK AAC Codec (including

those of Fraunhofer) may be obtained through Via Licensing

(www.vialicensing.com) or through the respective patent owners individually for

the purpose of encoding or decoding bit streams in products that are compliant

with the ISO/IEC MPEG audio standards. Please note that most manufacturers of

Android devices already license these patent claims through Via Licensing or

directly from the patent owners, and therefore FDK AAC Codec software may

already be covered under those patent licenses when it is used for those

licensed purposes only.

Commercially-licensed AAC software libraries, including floating-point versions

with enhanced sound quality, are also available from Fraunhofer. Users are

encouraged to check the Fraunhofer website for additional applications

information and documentation.

2.    COPYRIGHT LICENSE

Redistribution and use in source and binary forms, with or without modification,

are permitted without payment of copyright license fees provided that you

satisfy the following conditions:

You must retain the complete text of this software license in redistributions of

the FDK AAC Codec or your modifications thereto in source code form.

You must retain the complete text of this software license in the documentation

and/or other materials provided with redistributions of the FDK AAC Codec or

your modifications thereto in binary form. You must make available free of

charge copies of the complete source code of the FDK AAC Codec and your

modifications thereto to recipients of copies in binary form.

The name of Fraunhofer may not be used to endorse or promote products derived

from this library without prior written permission.

You may not charge copyright license fees for anyone to use, copy or distribute

the FDK AAC Codec software or your modifications thereto.

Your modified versions of the FDK AAC Codec must carry prominent notices stating

that you changed the software and the date of any change. For modified versions

of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"

must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK

AAC Codec Library for Android."

3.    NO PATENT LICENSE

NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without

limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.

Fraunhofer provides no warranty of patent non-infringement with respect to this

software.

You may use this FDK AAC Codec software or modifications thereto only for

purposes that are authorized by appropriate patent licenses.

4.    DISCLAIMER

This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright

holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,

including but not limited to the implied warranties of merchantability and

fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR

CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,

or consequential damages, including but not limited to procurement of substitute

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however caused and on any theory of liability, whether in contract, strict

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this software, even if advised of the possibility of such damage.

5.    CONTACT INFORMATION

Fraunhofer Institute for Integrated Circuits IIS

Attention: Audio and Multimedia Departments - FDK AAC LL

Am Wolfsmantel 33

91058 Erlangen, Germany

www.iis.fraunhofer.de/amm

amm-info@iis.fraunhofer.de

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

/**************************** SBR decoder library ******************************

   Author(s):

   Description:

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

/*!

  \file

  \brief  Sbr decoder

  This module provides the actual decoder implementation. The SBR data (side

  information) is already decoded. Only three functions are provided:

  \li 1.) createSbrDec(): One time initialization

  \li 2.) resetSbrDec(): Called by sbr_Apply() when the information contained in

  an SBR_HEADER_ELEMENT requires a reset and recalculation of important SBR

  structures. \li 3.) sbr_dec(): The actual decoder. Calls the different tools

  such as filterbanks, lppTransposer(), and calculateSbrEnvelope() [the envelope

  adjuster].

  \sa sbr_dec(), \ref documentationOverview

*/

#include "sbr_dec.h"

#include "sbr_ram.h"

#include "env_extr.h"

#include "env_calc.h"

#include "scale.h"

#include "FDK_matrixCalloc.h"

#include "hbe.h"

#include "genericStds.h"

#include "sbrdec_drc.h"

static void copyHarmonicSpectrum(int *xOverQmf, FIXP_DBL **qmfReal,

                                 FIXP_DBL **qmfImag, int noCols, int overlap,

                                 KEEP_STATES_SYNCED_MODE keepStatesSynced) {

  int patchBands;

  int patch, band, col, target, sourceBands, i;

  int numPatches = 0;

  int slotOffset = 0;

  FIXP_DBL **ppqmfReal = qmfReal + overlap;

  FIXP_DBL **ppqmfImag = qmfImag + overlap;

  if (keepStatesSynced == KEEP_STATES_SYNCED_NORMAL) {

    slotOffset = noCols - overlap - LPC_ORDER;

  }

  if (keepStatesSynced == KEEP_STATES_SYNCED_OUTDIFF) {

    ppqmfReal = qmfReal;

    ppqmfImag = qmfImag;

  }

  for (i = 1; i < MAX_NUM_PATCHES; i++) {

    if (xOverQmf[i] != 0) {

      numPatches++;

    }

  }

  for (patch = (MAX_STRETCH_HBE - 1); patch < numPatches; patch++) {

    patchBands = xOverQmf[patch + 1] - xOverQmf[patch];

    target = xOverQmf[patch];

    sourceBands = xOverQmf[MAX_STRETCH_HBE - 1] - xOverQmf[MAX_STRETCH_HBE - 2];

    while (patchBands > 0) {

      int numBands = sourceBands;

      int startBand = xOverQmf[MAX_STRETCH_HBE - 1] - 1;

      if (target + numBands >= xOverQmf[patch + 1]) {

        numBands = xOverQmf[patch + 1] - target;

      }

      if ((((target + numBands - 1) % 2) +

           ((xOverQmf[MAX_STRETCH_HBE - 1] - 1) % 2)) %

          2) {

        if (numBands == sourceBands) {

          numBands--;

        } else {

          startBand--;

        }

      }

      if (keepStatesSynced == KEEP_STATES_SYNCED_OUTDIFF) {

        for (col = slotOffset; col < overlap + LPC_ORDER; col++) {

          i = 0;

          for (band = numBands; band > 0; band--) {

            if ((target + band - 1 < 64) &&

                (target + band - 1 < xOverQmf[patch + 1])) {

              ppqmfReal[col][target + band - 1] = ppqmfReal[col][startBand - i];

              ppqmfImag[col][target + band - 1] = ppqmfImag[col][startBand - i];

              i++;

            }

          }

        }

      } else {

        for (col = slotOffset; col < noCols; col++) {

          i = 0;

          for (band = numBands; band > 0; band--) {

            if ((target + band - 1 < 64) &&

                (target + band - 1 < xOverQmf[patch + 1])) {

              ppqmfReal[col][target + band - 1] = ppqmfReal[col][startBand - i];

              ppqmfImag[col][target + band - 1] = ppqmfImag[col][startBand - i];

              i++;

            }

          }

        }

      }

      target += numBands;

      patchBands -= numBands;

    }

  }

}

/*!

  \brief      SBR decoder core function for one channel

  \image html  BufferMgmtDetailed-1632.png

  Besides the filter states of the QMF filter bank and the LPC-states of

  the LPP-Transposer, processing is mainly based on four buffers:

  #timeIn, #timeOut, #WorkBuffer2 and #OverlapBuffer. The #WorkBuffer2

  is reused for all channels and might be used by the core decoder, a

  static overlap buffer is required for each channel. Due to in-place

  processing, #timeIn and #timeOut point to identical locations.

  The spectral data is organized in so-called slots. Each slot

  contains 64 bands of complex data. The number of slots per frame

  depends on the frame size. For mp3PRO, there are 18 slots per frame

  and 6 slots per #OverlapBuffer. It is not necessary to have the slots

  in located consecutive address ranges.

  To optimize memory usage and to minimize the number of memory

  accesses, the memory management is organized as follows (slot numbers

  based on mp3PRO):

  1.) Input time domain signal is located in #timeIn. The last slots

  (0..5) of the spectral data of the previous frame are located in the

  #OverlapBuffer. In addition, #frameData of the current frame resides

  in the upper part of #timeIn.

  2.) During the cplxAnalysisQmfFiltering(), 32 samples from #timeIn are

  transformed into a slot of up to 32 complex spectral low band values at a

  time. The first spectral slot -- nr. 6 -- is written at slot number

  zero of #WorkBuffer2. #WorkBuffer2 will be completely filled with

  spectral data.

  3.) LPP-Transposition in lppTransposer() is processed on 24 slots. During the

  transposition, the high band part of the spectral data is replicated

  based on the low band data.

  Envelope Adjustment is processed on the high band part of the spectral

  data only by calculateSbrEnvelope().

  4.) The cplxSynthesisQmfFiltering() creates 64 time domain samples out

  of a slot of 64 complex spectral values at a time. The first 6 slots

  in #timeOut are filled from the results of spectral slots 0..5 in the

  #OverlapBuffer. The consecutive slots in timeOut are now filled with

  the results of spectral slots 6..17.

  5.) The preprocessed slots 18..23 have to be stored in the

  #OverlapBuffer.

*/

void sbr_dec(

    HANDLE_SBR_DEC hSbrDec,             /*!< handle to Decoder channel */

    LONG *timeIn,                       /*!< pointer to input time signal */

    LONG *timeOut,                      /*!< pointer to output time signal */

    HANDLE_SBR_DEC hSbrDecRight,        /*!< handle to Decoder channel right */

    LONG *timeOutRight,                 /*!< pointer to output time signal */

    const int strideOut,                /*!< Time data traversal strideOut */

    HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */

    HANDLE_SBR_FRAME_DATA hFrameData,   /*!< Control data of current frame */

    HANDLE_SBR_PREV_FRAME_DATA

        hPrevFrameData,        /*!< Some control data of last frame */

    const int applyProcessing, /*!< Flag for SBR operation */

    HANDLE_PS_DEC h_ps_d, const UINT flags, const int codecFrameSize,

    const INT sbrInDataHeadroom) {

  int i, slot, reserve;

  int saveLbScale;

  int lastSlotOffs;

  FIXP_DBL maxVal;

  /* temporary pointer / variable for QMF;

     required as we want to use temporary buffer

     creating one frame delay for HBE in LP mode */

  LONG *pTimeInQmf = timeIn;

  /* Number of QMF timeslots in the overlap buffer: */

  int ov_len = hSbrDec->LppTrans.pSettings->overlap;

  /* Number of QMF slots per frame */

  int noCols = hHeaderData->numberTimeSlots * hHeaderData->timeStep;

  /* create pointer array for data to use for HBE and legacy sbr */

  FIXP_DBL *pLowBandReal[(3 * 4) + 2 * ((1024) / (32) * (4) / 2)];

  FIXP_DBL *pLowBandImag[(3 * 4) + 2 * ((1024) / (32) * (4) / 2)];

  /* set pReal to where QMF analysis writes in case of legacy SBR */

  FIXP_DBL **pReal = pLowBandReal + ov_len;

  FIXP_DBL **pImag = pLowBandImag + ov_len;

  /* map QMF buffer to pointer array (Overlap + Frame)*/

  for (i = 0; i < noCols + ov_len; i++) {

    pLowBandReal[i] = hSbrDec->qmfDomainInCh->hQmfSlotsReal[i];

    pLowBandImag[i] = hSbrDec->qmfDomainInCh->hQmfSlotsImag[i];

  }

  if ((flags & SBRDEC_USAC_HARMONICSBR)) {

    /* in case of harmonic SBR and no HBE_LP map additional buffer for

       one more frame to pointer arry */

    for (i = 0; i < noCols; i++) {

      pLowBandReal[i + noCols + ov_len] = hSbrDec->hQmfHBESlotsReal[i];

      pLowBandImag[i + noCols + ov_len] = hSbrDec->hQmfHBESlotsImag[i];

    }

    /* shift scale values according to buffer */

    hSbrDec->scale_ov = hSbrDec->scale_lb;

    hSbrDec->scale_lb = hSbrDec->scale_hbe;

    /* set pReal to where QMF analysis writes in case of HBE */

    pReal += noCols;

    pImag += noCols;

    if (flags & SBRDEC_SKIP_QMF_ANA) {

      /* stereoCfgIndex3 with HBE */

      FDK_QmfDomain_QmfData2HBE(hSbrDec->qmfDomainInCh,

                                hSbrDec->hQmfHBESlotsReal,

                                hSbrDec->hQmfHBESlotsImag);

    } else {

      /* We have to move old hbe frame data to lb area of buffer */

      for (i = 0; i < noCols; i++) {

        FDKmemcpy(pLowBandReal[ov_len + i], hSbrDec->hQmfHBESlotsReal[i],

                  hHeaderData->numberOfAnalysisBands * sizeof(FIXP_DBL));

        FDKmemcpy(pLowBandImag[ov_len + i], hSbrDec->hQmfHBESlotsImag[i],

                  hHeaderData->numberOfAnalysisBands * sizeof(FIXP_DBL));

      }

    }

  }

  /*

    low band codec signal subband filtering

   */

  if (flags & SBRDEC_SKIP_QMF_ANA) {

    if (!(flags & SBRDEC_USAC_HARMONICSBR)) /* stereoCfgIndex3 w/o HBE */

      FDK_QmfDomain_WorkBuffer2ProcChannel(hSbrDec->qmfDomainInCh);

  } else {

    C_AALLOC_SCRATCH_START(qmfTemp, FIXP_DBL, 2 * (64));

    qmfAnalysisFiltering(&hSbrDec->qmfDomainInCh->fb, pReal, pImag,

                         &hSbrDec->qmfDomainInCh->scaling, pTimeInQmf,

                         0 + sbrInDataHeadroom, 1, qmfTemp);

    C_AALLOC_SCRATCH_END(qmfTemp, FIXP_DBL, 2 * (64));

  }

  /*

    Clear upper half of spectrum

  */

  if (!((flags & SBRDEC_USAC_HARMONICSBR) &&

        (hFrameData->sbrPatchingMode == 0))) {

    int nAnalysisBands = hHeaderData->numberOfAnalysisBands;

    if (!(flags & SBRDEC_LOW_POWER)) {

      for (slot = ov_len; slot < noCols + ov_len; slot++) {

        FDKmemclear(&pLowBandReal[slot][nAnalysisBands],

                    ((64) - nAnalysisBands) * sizeof(FIXP_DBL));

        FDKmemclear(&pLowBandImag[slot][nAnalysisBands],

                    ((64) - nAnalysisBands) * sizeof(FIXP_DBL));

      }

    } else {

      for (slot = ov_len; slot < noCols + ov_len; slot++) {

        FDKmemclear(&pLowBandReal[slot][nAnalysisBands],

                    ((64) - nAnalysisBands) * sizeof(FIXP_DBL));

      }

    }

  }

  /*

    Shift spectral data left to gain accuracy in transposer and adjustor

  */

  /* Range was increased from lsb to no_channels because in some cases (e.g.

     USAC conf eSbr_4_Pvc.mp4 and some HBE cases) it could be observed that the

     signal between lsb and no_channels is used for the patching process.

  */

  maxVal = maxSubbandSample(pReal, (flags & SBRDEC_LOW_POWER) ? NULL : pImag, 0,

                            hSbrDec->qmfDomainInCh->fb.no_channels, 0, noCols);

  reserve = fixMax(0, CntLeadingZeros(maxVal) - 1);

  reserve = fixMin(reserve,

                   DFRACT_BITS - 1 - hSbrDec->qmfDomainInCh->scaling.lb_scale);

  /* If all data is zero, lb_scale could become too large */

  rescaleSubbandSamples(pReal, (flags & SBRDEC_LOW_POWER) ? NULL : pImag, 0,

                        hSbrDec->qmfDomainInCh->fb.no_channels, 0, noCols,

                        reserve);

  hSbrDec->qmfDomainInCh->scaling.lb_scale += reserve;

  if ((flags & SBRDEC_USAC_HARMONICSBR)) {

    /* actually this is our hbe_scale */

    hSbrDec->scale_hbe = hSbrDec->qmfDomainInCh->scaling.lb_scale;

    /* the real lb_scale is stored in scale_lb from sbr */

    hSbrDec->qmfDomainInCh->scaling.lb_scale = hSbrDec->scale_lb;

  }

  /*

    save low band scale, wavecoding or parametric stereo may modify it

  */

  saveLbScale = hSbrDec->qmfDomainInCh->scaling.lb_scale;

  if (applyProcessing) {

    UCHAR *borders = hFrameData->frameInfo.borders;

    lastSlotOffs = borders[hFrameData->frameInfo.nEnvelopes] -

                   hHeaderData->numberTimeSlots;

    FIXP_DBL degreeAlias[(64)];

    PVC_DYNAMIC_DATA pvcDynamicData;

    pvcInitFrame(

        &hSbrDec->PvcStaticData, &pvcDynamicData,

        (hHeaderData->frameErrorFlag ? 0 : hHeaderData->bs_info.pvc_mode),

        hFrameData->ns, hHeaderData->timeStep,

        hHeaderData->freqBandData.lowSubband,

        hFrameData->frameInfo.pvcBorders[0], hFrameData->pvcID);

    if (!hHeaderData->frameErrorFlag && (hHeaderData->bs_info.pvc_mode > 0)) {

      pvcDecodeFrame(&hSbrDec->PvcStaticData, &pvcDynamicData, pLowBandReal,

                     pLowBandImag, ov_len,

                     SCALE2EXP(hSbrDec->qmfDomainInCh->scaling.ov_lb_scale),

                     SCALE2EXP(hSbrDec->qmfDomainInCh->scaling.lb_scale));

    }

    pvcEndFrame(&hSbrDec->PvcStaticData, &pvcDynamicData);

    /* The transposer will override most values in degreeAlias[].

       The array needs to be cleared at least from lowSubband to highSubband

       before. */

    if (flags & SBRDEC_LOW_POWER)

      FDKmemclear(&degreeAlias[hHeaderData->freqBandData.lowSubband],

                  (hHeaderData->freqBandData.highSubband -

                   hHeaderData->freqBandData.lowSubband) *

                      sizeof(FIXP_DBL));

    /*

      Inverse filtering of lowband and transposition into the SBR-frequency

      range

    */

    {

      KEEP_STATES_SYNCED_MODE keepStatesSyncedMode =

          ((flags & SBRDEC_USAC_HARMONICSBR) &&

           (hFrameData->sbrPatchingMode != 0))

              ? KEEP_STATES_SYNCED_NORMAL

              : KEEP_STATES_SYNCED_OFF;

      if (flags & SBRDEC_USAC_HARMONICSBR) {

        if (flags & SBRDEC_QUAD_RATE) {

          pReal -= 32;

          pImag -= 32;

        }

        if ((hSbrDec->savedStates == 0) && (hFrameData->sbrPatchingMode == 1)) {

          /* copy saved states from previous frame to legacy SBR lpc filterstate

           * buffer   */

          for (i = 0; i < LPC_ORDER + ov_len; i++) {

            FDKmemcpy(

                hSbrDec->LppTrans.lpcFilterStatesRealLegSBR[i],

                hSbrDec->codecQMFBufferReal[noCols - LPC_ORDER - ov_len + i],

                hSbrDec->hHBE->noChannels * sizeof(FIXP_DBL));

            FDKmemcpy(

                hSbrDec->LppTrans.lpcFilterStatesImagLegSBR[i],

                hSbrDec->codecQMFBufferImag[noCols - LPC_ORDER - ov_len + i],

                hSbrDec->hHBE->noChannels * sizeof(FIXP_DBL));

          }

        }

        /* saving unmodified QMF states in case we are switching from legacy SBR

         * to HBE */

        for (i = 0; i < hSbrDec->hHBE->noCols; i++) {

          FDKmemcpy(hSbrDec->codecQMFBufferReal[i], pLowBandReal[ov_len + i],

                    hSbrDec->hHBE->noChannels * sizeof(FIXP_DBL));

          FDKmemcpy(hSbrDec->codecQMFBufferImag[i], pLowBandImag[ov_len + i],

                    hSbrDec->hHBE->noChannels * sizeof(FIXP_DBL));

        }

        QmfTransposerApply(

            hSbrDec->hHBE, pReal, pImag, noCols, pLowBandReal, pLowBandImag,

            hSbrDec->LppTrans.lpcFilterStatesRealHBE,

            hSbrDec->LppTrans.lpcFilterStatesImagHBE,

            hFrameData->sbrPitchInBins, hSbrDec->scale_lb, hSbrDec->scale_hbe,

            &hSbrDec->qmfDomainInCh->scaling.hb_scale, hHeaderData->timeStep,

            borders[0], ov_len, keepStatesSyncedMode);

        if (flags & SBRDEC_QUAD_RATE) {

          int *xOverQmf = GetxOverBandQmfTransposer(hSbrDec->hHBE);

          copyHarmonicSpectrum(xOverQmf, pLowBandReal, pLowBandImag, noCols,

                               ov_len, keepStatesSyncedMode);

        }

      }

    }

    if ((flags & SBRDEC_USAC_HARMONICSBR) &&

        (hFrameData->sbrPatchingMode == 0)) {

      hSbrDec->prev_frame_lSbr = 0;

      hSbrDec->prev_frame_hbeSbr = 1;

      lppTransposerHBE(

          &hSbrDec->LppTrans, hSbrDec->hHBE, &hSbrDec->qmfDomainInCh->scaling,

          pLowBandReal, pLowBandImag, hHeaderData->timeStep, borders[0],

          lastSlotOffs, hHeaderData->freqBandData.nInvfBands,

          hFrameData->sbr_invf_mode, hPrevFrameData->sbr_invf_mode);

    } else {

      if (flags & SBRDEC_USAC_HARMONICSBR) {

        for (i = 0; i < LPC_ORDER + hSbrDec->LppTrans.pSettings->overlap; i++) {

          /*

          Store the unmodified qmf Slots values for upper part of spectrum

          (required for LPC filtering) required if next frame is a HBE frame

          */

          FDKmemcpy(hSbrDec->LppTrans.lpcFilterStatesRealHBE[i],

                    hSbrDec->qmfDomainInCh

                        ->hQmfSlotsReal[hSbrDec->hHBE->noCols - LPC_ORDER + i],

                    (64) * sizeof(FIXP_DBL));

          FDKmemcpy(hSbrDec->LppTrans.lpcFilterStatesImagHBE[i],

                    hSbrDec->qmfDomainInCh

                        ->hQmfSlotsImag[hSbrDec->hHBE->noCols - LPC_ORDER + i],

                    (64) * sizeof(FIXP_DBL));

        }

      }

      {

        hSbrDec->prev_frame_lSbr = 1;

        hSbrDec->prev_frame_hbeSbr = 0;

      }

      lppTransposer(

          &hSbrDec->LppTrans, &hSbrDec->qmfDomainInCh->scaling, pLowBandReal,

          degreeAlias,  // only used if useLP = 1

          pLowBandImag, flags & SBRDEC_LOW_POWER,

          hHeaderData->bs_info.sbr_preprocessing,

          hHeaderData->freqBandData.v_k_master[0], hHeaderData->timeStep,

          borders[0], lastSlotOffs, hHeaderData->freqBandData.nInvfBands,

          hFrameData->sbr_invf_mode, hPrevFrameData->sbr_invf_mode);

    }

    /*

      Adjust envelope of current frame.

    */

    if ((hFrameData->sbrPatchingMode !=

         hSbrDec->SbrCalculateEnvelope.sbrPatchingMode)) {

      ResetLimiterBands(hHeaderData->freqBandData.limiterBandTable,

                        &hHeaderData->freqBandData.noLimiterBands,

                        hHeaderData->freqBandData.freqBandTable[0],

                        hHeaderData->freqBandData.nSfb[0],

                        hSbrDec->LppTrans.pSettings->patchParam,

                        hSbrDec->LppTrans.pSettings->noOfPatches,

                        hHeaderData->bs_data.limiterBands,

                        hFrameData->sbrPatchingMode,

                        (flags & SBRDEC_USAC_HARMONICSBR) &&

                                (hFrameData->sbrPatchingMode == 0)

                            ? GetxOverBandQmfTransposer(hSbrDec->hHBE)

                            : NULL,

                        Get41SbrQmfTransposer(hSbrDec->hHBE));

      hSbrDec->SbrCalculateEnvelope.sbrPatchingMode =

          hFrameData->sbrPatchingMode;

    }

    calculateSbrEnvelope(

        &hSbrDec->qmfDomainInCh->scaling, &hSbrDec->SbrCalculateEnvelope,

        hHeaderData, hFrameData, &pvcDynamicData, pLowBandReal, pLowBandImag,

        flags & SBRDEC_LOW_POWER,

        degreeAlias, flags,

        (hHeaderData->frameErrorFlag || hPrevFrameData->frameErrorFlag));

#if (SBRDEC_MAX_HB_FADE_FRAMES > 0)

    /* Avoid hard onsets of high band */

    if (hHeaderData->frameErrorFlag) {

      if (hSbrDec->highBandFadeCnt < SBRDEC_MAX_HB_FADE_FRAMES) {

        hSbrDec->highBandFadeCnt += 1;

      }

    } else {

      if (hSbrDec->highBandFadeCnt >

          0) { /* Manipulate high band scale factor to get a smooth fade-in */

        hSbrDec->qmfDomainInCh->scaling.hb_scale += hSbrDec->highBandFadeCnt;

        hSbrDec->qmfDomainInCh->scaling.hb_scale =

            fMin(hSbrDec->qmfDomainInCh->scaling.hb_scale, DFRACT_BITS - 1);

        hSbrDec->highBandFadeCnt -= 1;

      }

    }

#endif

    /*

      Update hPrevFrameData (to be used in the next frame)

    */

    for (i = 0; i < hHeaderData->freqBandData.nInvfBands; i++) {

      hPrevFrameData->sbr_invf_mode[i] = hFrameData->sbr_invf_mode[i];

    }

    hPrevFrameData->coupling = hFrameData->coupling;

    hPrevFrameData->stopPos = borders[hFrameData->frameInfo.nEnvelopes];

    hPrevFrameData->ampRes = hFrameData->ampResolutionCurrentFrame;

    hPrevFrameData->prevSbrPitchInBins = hFrameData->sbrPitchInBins;

    /* could be done in extractFrameInfo_pvc() but hPrevFrameData is not

     * available there */

    FDKmemcpy(&hPrevFrameData->prevFrameInfo, &hFrameData->frameInfo,

              sizeof(FRAME_INFO));

  } else {

    /* rescale from lsb to nAnalysisBands in order to compensate scaling with

     * hb_scale in this area, done by synthesisFiltering*/

    int rescale;

    int lsb;

    int length;

    /* Reset hb_scale if no highband is present, because hb_scale is considered

     * in the QMF-synthesis */

    hSbrDec->qmfDomainInCh->scaling.hb_scale = saveLbScale;

    rescale = hSbrDec->qmfDomainInCh->scaling.hb_scale -

              hSbrDec->qmfDomainInCh->scaling.ov_lb_scale;

    lsb = hSbrDec->qmfDomainOutCh->fb.lsb;

    length = (hSbrDec->qmfDomainInCh->fb.no_channels - lsb);

    if ((rescale < 0) && (length > 0)) {

      if (!(flags & SBRDEC_LOW_POWER)) {

        for (i = 0; i < ov_len; i++) {

          scaleValues(&pLowBandReal[i][lsb], length, rescale);

          scaleValues(&pLowBandImag[i][lsb], length, rescale);

        }

      } else {

        for (i = 0; i < ov_len; i++) {

          scaleValues(&pLowBandReal[i][lsb], length, rescale);

        }

      }

    }

  }

  if (!(flags & SBRDEC_USAC_HARMONICSBR)) {

    int length = hSbrDec->qmfDomainInCh->fb.lsb;

    if (flags & SBRDEC_SYNTAX_USAC) {

      length = hSbrDec->qmfDomainInCh->fb.no_channels;

    }

    /* in case of legacy sbr saving of filter states here */

    for (i = 0; i < LPC_ORDER + ov_len; i++) {

      /*

        Store the unmodified qmf Slots values (required for LPC filtering)

      */

      if (!(flags & SBRDEC_LOW_POWER)) {

        FDKmemcpy(hSbrDec->LppTrans.lpcFilterStatesRealLegSBR[i],

                  pLowBandReal[noCols - LPC_ORDER + i],

                  length * sizeof(FIXP_DBL));

        FDKmemcpy(hSbrDec->LppTrans.lpcFilterStatesImagLegSBR[i],

                  pLowBandImag[noCols - LPC_ORDER + i],

                  length * sizeof(FIXP_DBL));

      } else

        FDKmemcpy(hSbrDec->LppTrans.lpcFilterStatesRealLegSBR[i],

                  pLowBandReal[noCols - LPC_ORDER + i],

                  length * sizeof(FIXP_DBL));

    }

  }

  /*

    Synthesis subband filtering.

  */

  if (!(flags & SBRDEC_PS_DECODED)) {

    if (!(flags & SBRDEC_SKIP_QMF_SYN)) {

      int outScalefactor = -(8);

      if (h_ps_d != NULL) {

        h_ps_d->procFrameBased = 1; /* we here do frame based processing */

      }

      sbrDecoder_drcApply(&hSbrDec->sbrDrcChannel, pLowBandReal,

                          (flags & SBRDEC_LOW_POWER) ? NULL : pLowBandImag,

                          hSbrDec->qmfDomainOutCh->fb.no_col, &outScalefactor);

      qmfChangeOutScalefactor(&hSbrDec->qmfDomainOutCh->fb, outScalefactor);

      {

        HANDLE_FREQ_BAND_DATA hFreq = &hHeaderData->freqBandData;

        int save_usb = hSbrDec->qmfDomainOutCh->fb.usb;

#if (QMF_MAX_SYNTHESIS_BANDS <= 64)

        C_AALLOC_SCRATCH_START(qmfTemp, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#else

        C_AALLOC_STACK_START(qmfTemp, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#endif

        if (hSbrDec->qmfDomainOutCh->fb.usb < hFreq->ov_highSubband) {

          /* we need to patch usb for this frame as overlap may contain higher

             frequency range if headerchange occured; fb. usb is always limited

             to maximum fb.no_channels; In case of wrongly decoded headers it

             might be that ov_highSubband is higher than the number of synthesis

             channels (fb.no_channels), which is forbidden, therefore we need to

             limit ov_highSubband with fMin function to avoid not allowed usb in

             synthesis filterbank. */

          hSbrDec->qmfDomainOutCh->fb.usb =

              fMin((UINT)hFreq->ov_highSubband,

                   (UINT)hSbrDec->qmfDomainOutCh->fb.no_channels);

        }

        {

          qmfSynthesisFiltering(

              &hSbrDec->qmfDomainOutCh->fb, pLowBandReal,

              (flags & SBRDEC_LOW_POWER) ? NULL : pLowBandImag,

              &hSbrDec->qmfDomainInCh->scaling,

              hSbrDec->LppTrans.pSettings->overlap, timeOut, strideOut,

              qmfTemp);

        }

        /* restore saved value */

        hSbrDec->qmfDomainOutCh->fb.usb = save_usb;

        hFreq->ov_highSubband = save_usb;

#if (QMF_MAX_SYNTHESIS_BANDS <= 64)

        C_AALLOC_SCRATCH_END(qmfTemp, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#else

        C_AALLOC_STACK_END(qmfTemp, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#endif

      }

    }

  } else { /* (flags & SBRDEC_PS_DECODED) */

    INT sdiff;

    INT scaleFactorHighBand, scaleFactorLowBand_ov, scaleFactorLowBand_no_ov,

        outScalefactor, outScalefactorR, outScalefactorL;

    HANDLE_QMF_FILTER_BANK synQmf = &hSbrDec->qmfDomainOutCh->fb;

    HANDLE_QMF_FILTER_BANK synQmfRight = &hSbrDecRight->qmfDomainOutCh->fb;

    /* adapt scaling */

    sdiff = hSbrDec->qmfDomainInCh->scaling.lb_scale -

            reserve; /* Scaling difference */

    scaleFactorHighBand = sdiff - hSbrDec->qmfDomainInCh->scaling.hb_scale;

    scaleFactorLowBand_ov = sdiff - hSbrDec->qmfDomainInCh->scaling.ov_lb_scale;

    scaleFactorLowBand_no_ov = sdiff - hSbrDec->qmfDomainInCh->scaling.lb_scale;

    /* Scale of low band overlapping QMF data */

    scaleFactorLowBand_ov =

        fMin(DFRACT_BITS - 1, fMax(-(DFRACT_BITS - 1), scaleFactorLowBand_ov));

    /* Scale of low band current QMF data     */

    scaleFactorLowBand_no_ov = fMin(

        DFRACT_BITS - 1, fMax(-(DFRACT_BITS - 1), scaleFactorLowBand_no_ov));

    /* Scale of current high band */

    scaleFactorHighBand =

        fMin(DFRACT_BITS - 1, fMax(-(DFRACT_BITS - 1), scaleFactorHighBand));

    if (h_ps_d->procFrameBased == 1) /* If we have switched from frame to slot

                                        based processing copy filter states */

    {                                /* procFrameBased will be unset later */

      /* copy filter states from left to right */

      /* was ((640)-(64))*sizeof(FIXP_QSS)

         flexible amount of synthesis bands needed for QMF based resampling

      */

      FDK_ASSERT(hSbrDec->qmfDomainInCh->pGlobalConf->nBandsSynthesis <=

                 QMF_MAX_SYNTHESIS_BANDS);

      synQmfRight->outScalefactor = synQmf->outScalefactor;

      FDKmemcpy(synQmfRight->FilterStates, synQmf->FilterStates,

                9 * hSbrDec->qmfDomainInCh->pGlobalConf->nBandsSynthesis *

                    sizeof(FIXP_QSS));

    }

    /* Feed delaylines when parametric stereo is switched on. */

    PreparePsProcessing(h_ps_d, pLowBandReal, pLowBandImag,

                        scaleFactorLowBand_ov);

    /* use the same synthese qmf values for left and right channel */

    synQmfRight->no_col = synQmf->no_col;

    synQmfRight->lsb = synQmf->lsb;

    synQmfRight->usb = synQmf->usb;

    int env = 0;

    {

#if (QMF_MAX_SYNTHESIS_BANDS <= 64)

      C_AALLOC_SCRATCH_START(pWorkBuffer, FIXP_DBL,

                             2 * QMF_MAX_SYNTHESIS_BANDS);

#else

      C_AALLOC_STACK_START(pWorkBuffer, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#endif

      int maxShift = 0;

      if (hSbrDec->sbrDrcChannel.enable != 0) {

        if (hSbrDec->sbrDrcChannel.prevFact_exp > maxShift) {

          maxShift = hSbrDec->sbrDrcChannel.prevFact_exp;

        }

        if (hSbrDec->sbrDrcChannel.currFact_exp > maxShift) {

          maxShift = hSbrDec->sbrDrcChannel.currFact_exp;

        }

        if (hSbrDec->sbrDrcChannel.nextFact_exp > maxShift) {

          maxShift = hSbrDec->sbrDrcChannel.nextFact_exp;

        }

      }

      /* copy DRC data to right channel (with PS both channels use the same DRC

       * gains) */

      FDKmemcpy(&hSbrDecRight->sbrDrcChannel, &hSbrDec->sbrDrcChannel,

                sizeof(SBRDEC_DRC_CHANNEL));

      outScalefactor = maxShift - (8);

      outScalefactorL = outScalefactorR =

          sbrInDataHeadroom + 1; /* +1: psDiffScale! (MPEG-PS) */

      for (i = 0; i < synQmf->no_col; i++) { /* ----- no_col loop ----- */

        /* qmf timeslot of right channel */

        FIXP_DBL *rQmfReal = pWorkBuffer;

        FIXP_DBL *rQmfImag = pWorkBuffer + synQmf->no_channels;

        {

          if (i ==

              h_ps_d->bsData[h_ps_d->processSlot].mpeg.aEnvStartStop[env]) {

            initSlotBasedRotation(h_ps_d, env,

                                  hHeaderData->freqBandData.highSubband);

            env++;

          }

          ApplyPsSlot(

              h_ps_d,             /* parametric stereo decoder handle  */

              (pLowBandReal + i), /* one timeslot of left/mono channel */

              (pLowBandImag + i), /* one timeslot of left/mono channel */

              rQmfReal,           /* one timeslot or right channel     */

              rQmfImag,           /* one timeslot or right channel     */

              scaleFactorLowBand_no_ov,

              (i < hSbrDec->LppTrans.pSettings->overlap)

                  ? scaleFactorLowBand_ov

                  : scaleFactorLowBand_no_ov,

              scaleFactorHighBand, synQmf->lsb, synQmf->usb);

        }

        sbrDecoder_drcApplySlot(/* right channel */

                                &hSbrDecRight->sbrDrcChannel, rQmfReal,

                                rQmfImag, i, synQmfRight->no_col, maxShift);

        sbrDecoder_drcApplySlot(/* left channel */

                                &hSbrDec->sbrDrcChannel, *(pLowBandReal + i),

                                *(pLowBandImag + i), i, synQmf->no_col,

                                maxShift);

        if (!(flags & SBRDEC_SKIP_QMF_SYN)) {

          qmfChangeOutScalefactor(synQmf, outScalefactor);

          qmfChangeOutScalefactor(synQmfRight, outScalefactor);

          qmfSynthesisFilteringSlot(

              synQmfRight, rQmfReal, /* QMF real buffer */

              rQmfImag,              /* QMF imag buffer */

              outScalefactorL, outScalefactorL,

              timeOutRight + (i * synQmf->no_channels * strideOut), strideOut,

              pWorkBuffer);

          qmfSynthesisFilteringSlot(

              synQmf, *(pLowBandReal + i), /* QMF real buffer */

              *(pLowBandImag + i),         /* QMF imag buffer */

              outScalefactorR, outScalefactorR,

              timeOut + (i * synQmf->no_channels * strideOut), strideOut,

              pWorkBuffer);

        }

      } /* no_col loop  i  */

#if (QMF_MAX_SYNTHESIS_BANDS <= 64)

      C_AALLOC_SCRATCH_END(pWorkBuffer, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#else

      C_AALLOC_STACK_END(pWorkBuffer, FIXP_DBL, 2 * QMF_MAX_SYNTHESIS_BANDS);

#endif

    }

  }

  sbrDecoder_drcUpdateChannel(&hSbrDec->sbrDrcChannel);

  /*

    Update overlap buffer

    Even bands above usb are copied to avoid outdated spectral data in case

    the stop frequency raises.

  */

  if (!(flags & SBRDEC_SKIP_QMF_SYN)) {

    {

      FDK_QmfDomain_SaveOverlap(hSbrDec->qmfDomainInCh, 0);

      FDK_ASSERT(hSbrDec->qmfDomainInCh->scaling.ov_lb_scale == saveLbScale);

    }

  }

  hSbrDec->savedStates = 0;

  /* Save current frame status */

  hPrevFrameData->frameErrorFlag = hHeaderData->frameErrorFlag;

  hSbrDec->applySbrProc_old = applyProcessing;

} /* sbr_dec() */

/*!

  \brief     Creates sbr decoder structure

  \return    errorCode, 0 if successful

*/

SBR_ERROR

createSbrDec(SBR_CHANNEL *hSbrChannel,

             HANDLE_SBR_HEADER_DATA hHeaderData, /*!< Static control data */

             TRANSPOSER_SETTINGS *pSettings,

             const int downsampleFac, /*!< Downsampling factor */

             const UINT qmfFlags, /*!< flags -> 1: HQ/LP selector, 2: CLDFB */

             const UINT flags, const int overlap,

             int chan, /*!< Channel for which to assign buffers etc. */

             int codecFrameSize)

{

  SBR_ERROR err = SBRDEC_OK;

  int timeSlots =

      hHeaderData->numberTimeSlots; /* Number of SBR slots per frame */

  int noCols =

      timeSlots * hHeaderData->timeStep; /* Number of QMF slots per frame */

  HANDLE_SBR_DEC hs = &(hSbrChannel->SbrDec);

#if (SBRDEC_MAX_HB_FADE_FRAMES > 0)

  hs->highBandFadeCnt = SBRDEC_MAX_HB_FADE_FRAMES;

#endif

  hs->scale_hbe = 15;

  hs->scale_lb = 15;

  hs->scale_ov = 15;

  hs->prev_frame_lSbr = 0;

  hs->prev_frame_hbeSbr = 0;

  hs->codecFrameSize = codecFrameSize;

  /*

    create envelope calculator

  */

  err = createSbrEnvelopeCalc(&hs->SbrCalculateEnvelope, hHeaderData, chan,

                              flags);

  if (err != SBRDEC_OK) {

    return err;

  }

  initSbrPrevFrameData(&hSbrChannel->prevFrameData, timeSlots);

  /*