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+
+/* -----------------------------------------------------------------------------------------------------------
+Software License for The Fraunhofer FDK AAC Codec Library for Android
+
+© Copyright  1995 - 2012 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 goods or services; loss of use, data, or profits,
+or business interruption, however caused and on any theory of liability, whether in contract, strict
+liability, or tort (including negligence), arising in any way out of the use of 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
+----------------------------------------------------------------------------------------------------------- */
+
+#include "tran_det.h"
+
+#include "fram_gen.h"
+#include "sbr_ram.h"
+#include "sbr_misc.h"
+
+#include "genericStds.h"
+
+#define NORM_QMF_ENERGY 5.684341886080801486968994140625e-14 /* 2^-44 */
+
+/* static FIXP_DBL ABS_THRES = fixMax( FL2FXCONST_DBL(1.28e5 *  NORM_QMF_ENERGY), (FIXP_DBL)1)  Minimum threshold for detecting changes */
+#define ABS_THRES ((FIXP_DBL)16)
+
+/*******************************************************************************
+ Functionname:  spectralChange
+ *******************************************************************************
+ \brief   Calculates a measure for the spectral change within the frame
+
+ The function says how good it would be to split the frame at the given border
+ position into 2 envelopes.
+
+ The return value delta_sum is scaled with the factor 1/64
+
+ \return  calculated value
+*******************************************************************************/
+static FIXP_DBL spectralChange(FIXP_DBL Energies[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS],
+                               INT *scaleEnergies,
+                               FIXP_DBL EnergyTotal,
+                               INT nSfb,
+                               INT start,
+                               INT border,
+                               INT stop)
+{
+  INT i,j;
+  INT len1,len2;
+  FIXP_DBL delta,tmp0,tmp1,tmp2;
+  FIXP_DBL accu1,accu2,delta_sum,result;
+
+  FDK_ASSERT(scaleEnergies[0] >= 0);
+
+  /* equal for aac (would be not equal for mp3) */
+  len1 = border-start;
+  len2 = stop-border;
+
+  /* prefer borders near the middle of the frame */
+  FIXP_DBL   pos_weight;
+  pos_weight = FL2FXCONST_DBL(0.5f) - (len1*GetInvInt(len1+len2));
+  pos_weight = /*FL2FXCONST_DBL(1.0)*/ (FIXP_DBL)MAXVAL_DBL - (fMult(pos_weight, pos_weight)<<2);
+
+  delta_sum = FL2FXCONST_DBL(0.0f);
+
+  /* Sum up energies of all QMF-timeslots for both halfs */
+  for (j=0; j<nSfb; j++) {
+    #define NRG_SCALE  3
+    /* init with some energy to prevent division by zero
+       and to prevent splitting for very low levels */
+    accu1 = ((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY*8.0/32))) << fixMin(scaleEnergies[0],25))>>NRG_SCALE;  /* complex init for compare with original version */
+    accu2 = ((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY*8.0/32))) << fixMin(scaleEnergies[0],25))>>NRG_SCALE;  /* can be simplified in dsp implementation */
+
+    /* Sum up energies in first half */
+    for (i=start; i<border; i++) {
+      accu1 += (Energies[i][j]>>NRG_SCALE);
+    }
+
+    /* Sum up energies in second half */
+    for (i=border; i<stop; i++) {
+      accu2 += (Energies[i][j]>>NRG_SCALE);
+    }
+
+    /* Energy change in current band */
+    tmp0 = CalcLdData(accu2);
+    tmp1 = CalcLdData(accu1);
+    tmp2 = (tmp0 - tmp1 + CalcLdData(len1)-CalcLdData(len2));
+    delta = fixp_abs(fMult(tmp2, FL2FXCONST_DBL(0.6931471806f)));
+
+    /* Weighting with amplitude ratio of this band */
+    result = (EnergyTotal == FL2FXCONST_DBL(0.0f))
+            ? FL2FXCONST_DBL(0.f)
+            : FDKsbrEnc_LSI_divide_scale_fract( (accu1+accu2),
+                                      (EnergyTotal>>NRG_SCALE)+(FIXP_DBL)1,
+                                      (FIXP_DBL)MAXVAL_DBL >> fixMin(scaleEnergies[0],(DFRACT_BITS-1)) );
+
+    delta_sum += (FIXP_DBL)(fMult(sqrtFixp(result), delta));
+  }
+
+  return fMult(delta_sum, pos_weight);
+}
+
+
+/*******************************************************************************
+ Functionname:  addLowbandEnergies
+ *******************************************************************************
+ \brief   Calculates total lowband energy
+
+ The return value nrgTotal is scaled by the factor (1/32.0)
+
+ \return  total energy in the lowband
+*******************************************************************************/
+static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies,
+                                   int       *scaleEnergies,
+                                   int        YBufferWriteOffset,
+                                   int        nrgSzShift,
+                                   int        tran_off,
+                                   UCHAR     *freqBandTable,
+                                   int        slots)
+{
+  FIXP_DBL nrgTotal;
+  FIXP_DBL accu1 = FL2FXCONST_DBL(0.0f);
+  FIXP_DBL accu2 = FL2FXCONST_DBL(0.0f);
+  int tran_offdiv2 = tran_off>>nrgSzShift;
+  int ts,k;
+
+  /* Sum up lowband energy from one frame at offset tran_off */
+  for (ts=tran_offdiv2; ts<YBufferWriteOffset; ts++) {
+    for (k = 0; k < freqBandTable[0]; k++) {
+      accu1 += Energies[ts][k] >> 6;
+    }
+  }
+  for (; ts<tran_offdiv2+(slots>>nrgSzShift); ts++) {
+    for (k = 0; k < freqBandTable[0]; k++) {
+      accu2 += Energies[ts][k] >> 6;
+    }
+  }
+
+  nrgTotal = ( (accu1 >> fixMin(scaleEnergies[0],(DFRACT_BITS-1)))
+           +   (accu2 >> fixMin(scaleEnergies[1],(DFRACT_BITS-1))) ) << (2);
+
+  return(nrgTotal);
+}
+
+
+/*******************************************************************************
+ Functionname:  addHighbandEnergies
+ *******************************************************************************
+ \brief   Add highband energies
+
+ Highband energies are mapped to an array with smaller dimension:
+ Its time resolution is only 1 SBR-timeslot and its frequency resolution
+ is 1 SBR-band. Therefore the data to be fed into the spectralChange
+ function is reduced.
+
+ The values EnergiesM are scaled by the factor (1/32.0) and scaleEnergies[0]
+ The return value nrgTotal is scaled by the factor (1/32.0)
+
+ \return  total energy in the highband
+*******************************************************************************/
+
+static FIXP_DBL addHighbandEnergies(FIXP_DBL **RESTRICT Energies, /*!< input */
+                                    INT       *scaleEnergies,
+                                    FIXP_DBL   EnergiesM[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS], /*!< Combined output */
+                                    UCHAR     *RESTRICT freqBandTable,
+                                    INT        nSfb,
+                                    INT        sbrSlots,
+                                    INT        timeStep)
+{
+  INT i,j,k,slotIn,slotOut,scale;
+  INT li,ui;
+  FIXP_DBL nrgTotal;
+  FIXP_DBL accu = FL2FXCONST_DBL(0.0f);
+
+  /* Combine QMF-timeslots to SBR-timeslots,
+     combine QMF-bands to SBR-bands,
+     combine Left and Right channel */
+  for (slotOut=0; slotOut<sbrSlots; slotOut++) {
+    slotIn = 2*slotOut;
+
+    for (j=0; j<nSfb; j++) {
+      accu = FL2FXCONST_DBL(0.0f);
+
+      li = freqBandTable[j];
+      ui = freqBandTable[j + 1];
+
+      for (k=li; k<ui; k++) {
+        for (i=0; i<timeStep; i++) {
+         accu += (Energies[(slotIn+i)>>1][k] >> 5);
+        }
+      }
+      EnergiesM[slotOut][j] = accu;
+    }
+  }
+
+  scale = fixMin(8,scaleEnergies[0]);      /* scale energies down before add up */
+
+  if ((scaleEnergies[0]-1) > (DFRACT_BITS-1) )
+    nrgTotal = FL2FXCONST_DBL(0.0f);
+  else {
+    /* Now add all energies */
+    accu = FL2FXCONST_DBL(0.0f);
+    for (slotOut=0; slotOut<sbrSlots; slotOut++) {
+      for (j=0; j<nSfb; j++) {
+        accu += (EnergiesM[slotOut][j] >> scale);
+      }
+    }
+    nrgTotal = accu >> (scaleEnergies[0]-scale);
+  }
+
+  return(nrgTotal);
+}
+
+
+/*******************************************************************************
+ Functionname:  FDKsbrEnc_frameSplitter
+ *******************************************************************************
+ \brief   Decides if a FIXFIX-frame shall be splitted into 2 envelopes
+
+ If no transient has been detected before, the frame can still be splitted
+ into 2 envelopes.
+*******************************************************************************/
+void
+FDKsbrEnc_frameSplitter(FIXP_DBL **Energies,
+                        INT *scaleEnergies,
+                        HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
+                        UCHAR *freqBandTable,
+                        UCHAR *tran_vector,
+                        int YBufferWriteOffset,
+                        int YBufferSzShift,
+                        int nSfb,
+                        int timeStep,
+                        int no_cols)
+{
+  if (tran_vector[1]==0) /* no transient was detected */
+  {
+    FIXP_DBL delta;
+    FIXP_DBL EnergiesM[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS];
+    FIXP_DBL EnergyTotal,newLowbandEnergy,newHighbandEnergy;
+    INT border;
+    INT sbrSlots = fMultI(GetInvInt(timeStep),no_cols);
+
+    FDK_ASSERT( sbrSlots * timeStep == no_cols );
+
+    /*
+      Get Lowband-energy over a range of 2 frames (Look half a frame back and ahead).
+    */
+    newLowbandEnergy = addLowbandEnergies(Energies,
+                                          scaleEnergies,
+                                          YBufferWriteOffset,
+                                          YBufferSzShift,
+                                          h_sbrTransientDetector->tran_off,
+                                          freqBandTable,
+                                          no_cols);
+
+    newHighbandEnergy = addHighbandEnergies(Energies,
+                                            scaleEnergies,
+                                            EnergiesM,
+                                            freqBandTable,
+                                            nSfb,
+                                            sbrSlots,
+                                            timeStep);
+
+    if ( h_sbrTransientDetector->frameShift != 0 ) {
+      if (tran_vector[1]==0)
+        tran_vector[0] = 0;
+    } else
+    {
+      /* prevLowBandEnergy: Corresponds to 1 frame, starting with half a frame look-behind
+         newLowbandEnergy:  Corresponds to 1 frame, starting in the middle of the current frame */
+      EnergyTotal = (newLowbandEnergy + h_sbrTransientDetector->prevLowBandEnergy) >> 1;
+      EnergyTotal += newHighbandEnergy;
+      /* The below border should specify the same position as the middle border
+         of a FIXFIX-frame with 2 envelopes. */
+      border = (sbrSlots+1) >> 1;
+
+      delta = spectralChange(EnergiesM,
+                             scaleEnergies,
+                             EnergyTotal,
+                             nSfb,
+                             0,
+                             border,
+                             sbrSlots);
+
+      if (delta > (h_sbrTransientDetector->split_thr >> LD_DATA_SHIFT)) /* delta scaled by 1/64 */
+        tran_vector[0] = 1; /* Set flag for splitting */
+      else
+        tran_vector[0] = 0;
+    }
+
+    /* Update prevLowBandEnergy */
+    h_sbrTransientDetector->prevLowBandEnergy = newLowbandEnergy;
+    h_sbrTransientDetector->prevHighBandEnergy = newHighbandEnergy;
+  }
+}
+
+/*
+ * Calculate transient energy threshold for each QMF band
+ */
+static void
+calculateThresholds(FIXP_DBL **RESTRICT Energies,
+                    INT       *RESTRICT scaleEnergies,
+                    FIXP_DBL  *RESTRICT thresholds,
+                    int        YBufferWriteOffset,
+                    int        YBufferSzShift,
+                    int        noCols,
+                    int        noRows,
+                    int        tran_off)
+{
+  FIXP_DBL mean_val,std_val,temp;
+  FIXP_DBL i_noCols;
+  FIXP_DBL i_noCols1;
+  FIXP_DBL accu,accu0,accu1;
+  int scaleFactor0,scaleFactor1,commonScale;
+  int i,j;
+
+  i_noCols  = GetInvInt(noCols + tran_off ) << YBufferSzShift;
+  i_noCols1 = GetInvInt(noCols + tran_off - 1) << YBufferSzShift;
+
+  /* calc minimum scale of energies of previous and current frame */
+  commonScale = fixMin(scaleEnergies[0],scaleEnergies[1]);
+
+  /* calc scalefactors to adapt energies to common scale */
+  scaleFactor0 = fixMin((scaleEnergies[0]-commonScale), (DFRACT_BITS-1));
+  scaleFactor1 = fixMin((scaleEnergies[1]-commonScale), (DFRACT_BITS-1));
+
+  FDK_ASSERT((scaleFactor0 >= 0) && (scaleFactor1 >= 0));
+
+  /* calculate standard deviation in every subband */
+  for (i=0; i<noRows; i++)
+  {
+    int startEnergy = (tran_off>>YBufferSzShift);
+    int endEnergy = ((noCols>>YBufferSzShift)+tran_off);
+    int shift;
+
+    /* calculate mean value over decimated energy values (downsampled by 2). */
+    accu0 = accu1 = FL2FXCONST_DBL(0.0f);
+
+    for (j=startEnergy; j<YBufferWriteOffset; j++)
+      accu0 += fMult(Energies[j][i], i_noCols);
+    for (; j<endEnergy; j++)
+      accu1 += fMult(Energies[j][i], i_noCols);
+
+    mean_val = (accu0 >> scaleFactor0) + (accu1 >> scaleFactor1);  /* average */
+    shift    = fixMax(0,CountLeadingBits(mean_val)-6);             /* -6 to keep room for accumulating upto N = 24 values */
+
+    /* calculate standard deviation */
+    accu = FL2FXCONST_DBL(0.0f);
+
+    /* summe { ((mean_val-nrg)^2) * i_noCols1 } */
+    for (j=startEnergy; j<YBufferWriteOffset; j++) {
+      temp = ((FIXP_DBL)mean_val - ((FIXP_DBL)Energies[j][i] >> scaleFactor0))<<shift;
+      temp = fPow2(temp);
+      temp = fMult(temp, i_noCols1);
+      accu += temp;
+    }
+    for (; j<endEnergy; j++) {
+      temp = ((FIXP_DBL)mean_val - ((FIXP_DBL)Energies[j][i] >> scaleFactor1))<<shift;
+      temp = fPow2(temp);
+      temp = fMult(temp, i_noCols1);
+      accu += temp;
+    }
+
+    std_val = sqrtFixp(accu)>>shift;     /* standard deviation */
+
+    /*
+    Take new threshold as average of calculated standard deviation ratio
+    and old threshold if greater than absolute threshold
+    */
+    temp = ( commonScale<=(DFRACT_BITS-1) )
+            ? fMult(FL2FXCONST_DBL(0.66f), thresholds[i]) + (fMult(FL2FXCONST_DBL(0.34f), std_val) >> commonScale)
+            : (FIXP_DBL) 0;
+
+    thresholds[i] = fixMax(ABS_THRES,temp);
+
+    FDK_ASSERT(commonScale >= 0);
+  }
+}
+
+/*
+ * Calculate transient levels for each QMF time slot.
+ */
+static void
+extractTransientCandidates(FIXP_DBL  **RESTRICT Energies,
+                           INT        *RESTRICT scaleEnergies,
+                           FIXP_DBL   *RESTRICT thresholds,
+                           FIXP_DBL   *RESTRICT transients,
+                           int         YBufferWriteOffset,
+                           int         YBufferSzShift,
+                           int         noCols,
+                           int         start_band,
+                           int         stop_band,
+                           int         tran_off,
+                           int         addPrevSamples)
+{
+  FIXP_DBL i_thres;
+  C_ALLOC_SCRATCH_START(EnergiesTemp, FIXP_DBL, 2*QMF_MAX_TIME_SLOTS);
+  FIXP_DBL *RESTRICT pEnergiesTemp = EnergiesTemp;
+  int tmpScaleEnergies0, tmpScaleEnergies1;
+  int endCond;
+  int startEnerg,endEnerg;
+  int i,j,jIndex,jpBM;
+
+  tmpScaleEnergies0 = scaleEnergies[0];
+  tmpScaleEnergies1 = scaleEnergies[1];
+
+  /* Scale value for first energies, upto YBufferWriteOffset */
+  tmpScaleEnergies0 = fixMin(tmpScaleEnergies0, MAX_SHIFT_DBL);
+  /* Scale value for first energies, from YBufferWriteOffset upwards */
+  tmpScaleEnergies1 = fixMin(tmpScaleEnergies1, MAX_SHIFT_DBL);
+
+  FDK_ASSERT((tmpScaleEnergies0 >= 0) && (tmpScaleEnergies1 >= 0));
+
+  /* Keep addPrevSamples extra previous transient candidates. */
+  FDKmemmove(transients, transients + noCols - addPrevSamples, (tran_off+addPrevSamples) * sizeof (FIXP_DBL));
+  FDKmemclear(transients + tran_off + addPrevSamples, noCols * sizeof (FIXP_DBL));
+
+  endCond = noCols; /* Amount of new transient values to be calculated. */
+  startEnerg = (tran_off-3)>>YBufferSzShift; /* >>YBufferSzShift because of amount of energy values. -3 because of neighbors being watched. */
+  endEnerg = ((noCols+ (YBufferWriteOffset<<YBufferSzShift))-1)>>YBufferSzShift; /* YBufferSzShift shifts because of half energy values. */
+
+  /* Compute differential values with two different weightings in every subband */
+  for (i=start_band; i<stop_band; i++)
+  {
+    FIXP_DBL thres = thresholds[i];
+
+    if((LONG)thresholds[i]>=256)
+      i_thres = (LONG)( (LONG)MAXVAL_DBL / ((((LONG)thresholds[i]))+1) )<<(32-24);
+    else
+      i_thres = (LONG)MAXVAL_DBL;
+
+    /* Copy one timeslot and de-scale and de-squish */
+    if (YBufferSzShift == 1) {
+      for(j=startEnerg; j<YBufferWriteOffset; j++) {
+        FIXP_DBL tmp = Energies[j][i];
+        EnergiesTemp[(j<<1)+1] = EnergiesTemp[j<<1] = tmp>>tmpScaleEnergies0;
+      }
+      for(; j<=endEnerg; j++) {
+        FIXP_DBL tmp = Energies[j][i];
+        EnergiesTemp[(j<<1)+1] = EnergiesTemp[j<<1] = tmp>>tmpScaleEnergies1;
+      }
+    } else {
+      for(j=startEnerg; j<YBufferWriteOffset; j++) {
+        FIXP_DBL tmp = Energies[j][i];
+        EnergiesTemp[j] = tmp>>tmpScaleEnergies0;
+      }
+      for(; j<=endEnerg; j++) {
+        FIXP_DBL tmp = Energies[j][i];
+        EnergiesTemp[j] = tmp>>tmpScaleEnergies1;
+      }
+    }
+
+    /* Detect peaks in energy values. */
+
+    jIndex = tran_off;
+    jpBM = jIndex+addPrevSamples;
+
+    for (j=endCond; j--; jIndex++, jpBM++)
+    {
+
+      FIXP_DBL delta, tran;
+      int d;
+
+      delta = (FIXP_DBL)0;
+      tran  = (FIXP_DBL)0;
+
+      for (d=1; d<4; d++) {
+        delta += pEnergiesTemp[jIndex+d]; /* R */
+        delta -= pEnergiesTemp[jIndex-d]; /* L */
+        delta -= thres;
+
+        if ( delta > (FIXP_DBL)0 ) {
+          tran += fMult(i_thres, delta);
+        }
+      }
+      transients[jpBM] += tran;
+    }
+  }
+  C_ALLOC_SCRATCH_END(EnergiesTemp, FIXP_DBL, 2*QMF_MAX_TIME_SLOTS);
+}
+
+void
+FDKsbrEnc_transientDetect(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTran,
+                          FIXP_DBL **Energies,
+                          INT *scaleEnergies,
+                          UCHAR *transient_info,
+                          int YBufferWriteOffset,
+                          int YBufferSzShift,
+                          int timeStep,
+                          int frameMiddleBorder)
+{
+  int no_cols = h_sbrTran->no_cols;
+  int qmfStartSample;
+  int addPrevSamples;
+  int timeStepShift=0;
+  int i, cond;
+
+  /* Where to start looking for transients in the transient candidate buffer */
+  qmfStartSample = timeStep * frameMiddleBorder;
+  /* We need to look one value backwards in the transients, so we might need one more previous value. */
+  addPrevSamples = (qmfStartSample > 0) ? 0: 1;
+
+  switch (timeStep) {
+    case 1: timeStepShift = 0; break;
+    case 2: timeStepShift = 1; break;
+    case 4: timeStepShift = 2; break;
+  }
+
+  calculateThresholds(Energies,
+                      scaleEnergies,
+                      h_sbrTran->thresholds,
+                      YBufferWriteOffset,
+                      YBufferSzShift,
+                      h_sbrTran->no_cols,
+                      h_sbrTran->no_rows,
+                      h_sbrTran->tran_off);
+
+  extractTransientCandidates(Energies,
+                             scaleEnergies,
+                             h_sbrTran->thresholds,
+                             h_sbrTran->transients,
+                             YBufferWriteOffset,
+                             YBufferSzShift,
+                             h_sbrTran->no_cols,
+                             0,
+                             h_sbrTran->no_rows,
+                             h_sbrTran->tran_off,
+                             addPrevSamples );
+
+  transient_info[0] = 0;
+  transient_info[1] = 0;
+  transient_info[2] = 0;
+
+  /* Offset by the amount of additional previous transient candidates being kept. */
+  qmfStartSample += addPrevSamples;
+
+  /* Check for transients in second granule (pick the last value of subsequent values)  */
+  for (i=qmfStartSample; i<qmfStartSample + no_cols; i++) {
+    cond =    (h_sbrTran->transients[i] < fMult(FL2FXCONST_DBL(0.9f), h_sbrTran->transients[i - 1]) )
+           && (h_sbrTran->transients[i - 1] > h_sbrTran->tran_thr);
+
+    if (cond) {
+      transient_info[0] = (i - qmfStartSample)>>timeStepShift;
+      transient_info[1] = 1;
+      break;
+    }
+  }
+
+  if ( h_sbrTran->frameShift != 0) {
+      /* transient prediction for LDSBR */
+      /* Check for transients in first <frameShift> qmf-slots of second frame */
+      for (i=qmfStartSample+no_cols; i<qmfStartSample + no_cols+h_sbrTran->frameShift; i++) {
+
+        cond =    (h_sbrTran->transients[i] < fMult(FL2FXCONST_DBL(0.9f), h_sbrTran->transients[i - 1]) )
+               && (h_sbrTran->transients[i - 1] > h_sbrTran->tran_thr);
+
+        if (cond) {
+          int pos = (int) ( (i - qmfStartSample-no_cols) >> timeStepShift );
+          if ((pos < 3) && (transient_info[1]==0)) {
+            transient_info[2] = 1;
+          }
+          break;
+        }
+      }
+  }
+}
+
+int
+FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
+                                   INT   frameSize,
+                                   INT   sampleFreq,
+                                   sbrConfigurationPtr params,
+                                   int   tran_fc,
+                                   int   no_cols,
+                                   int   no_rows,
+                                   int   YBufferWriteOffset,
+                                   int   YBufferSzShift,
+                                   int   frameShift,
+                                   int   tran_off)
+{
+    INT totalBitrate = params->codecSettings.standardBitrate * params->codecSettings.nChannels;
+    INT codecBitrate = params->codecSettings.bitRate;
+    FIXP_DBL bitrateFactor_fix, framedur_fix;
+    INT scale_0, scale_1;
+
+    FDKmemclear(h_sbrTransientDetector,sizeof(SBR_TRANSIENT_DETECTOR));
+
+    h_sbrTransientDetector->frameShift = frameShift;
+    h_sbrTransientDetector->tran_off = tran_off;
+
+    if(codecBitrate) {
+      bitrateFactor_fix = fDivNorm((FIXP_DBL)totalBitrate, (FIXP_DBL)(codecBitrate<<2),&scale_0);
+    }
+    else {
+      bitrateFactor_fix = FL2FXCONST_DBL(1.0/4.0);
+      scale_0 = 0;
+    }
+
+    framedur_fix = fDivNorm(frameSize, sampleFreq);
+
+    /* The longer the frames, the more often should the FIXFIX-
+    case transmit 2 envelopes instead of 1.
+    Frame durations below 10 ms produce the highest threshold
+    so that practically always only 1 env is transmitted. */
+    FIXP_DBL tmp = framedur_fix - FL2FXCONST_DBL(0.010);
+
+    tmp = fixMax(tmp, FL2FXCONST_DBL(0.0001));
+    tmp = fDivNorm(FL2FXCONST_DBL(0.000075), fPow2(tmp), &scale_1);
+
+    scale_1 = -(scale_1 + scale_0 + 2);
+
+    FDK_ASSERT(no_cols <= QMF_MAX_TIME_SLOTS);
+    FDK_ASSERT(no_rows <= QMF_CHANNELS);
+
+    h_sbrTransientDetector->no_cols = no_cols;
+    h_sbrTransientDetector->tran_thr = (FIXP_DBL)((params->tran_thr << (32-24-1)) / no_rows);
+    h_sbrTransientDetector->tran_fc = tran_fc;
+
+    if (scale_1>=0) {
+      h_sbrTransientDetector->split_thr = fMult(tmp, bitrateFactor_fix) >> scale_1;
+    }
+    else {
+      h_sbrTransientDetector->split_thr = fMult(tmp, bitrateFactor_fix) << (-scale_1);
+    }
+
+    h_sbrTransientDetector->no_rows = no_rows;
+    h_sbrTransientDetector->mode = params->tran_det_mode;
+    h_sbrTransientDetector->prevLowBandEnergy = FL2FXCONST_DBL(0.0f);
+
+    return (0);
+}
+