AAC/SBR encoder improvements

* AAC-Encoder

  - AAC-ELD core encoder audio quality tuning. Update tuning tables, configure
    bitreservoir size and adapt afterburner iteration value.
     Modified file(s):
        libAACenc/src/aacenc.h
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/adj_thr.cpp
        libAACenc/src/adj_thr.h
        libAACenc/src/adj_thr_data.h
        libAACenc/src/bandwidth.cpp
        libAACenc/src/pnsparam.cpp
        libAACenc/src/qc_main.cpp

   - Introduze dead zone quantizer for ELD to improve audio quality at certain
     configurations.
     Modified file(s):
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/adj_thr.cpp
        libAACenc/src/adj_thr.h
        libAACenc/src/qc_data.h
        libAACenc/src/qc_main.cpp
        libAACenc/src/quantize.cpp
        libAACenc/src/quantize.h
        libAACenc/src/sf_estim.cpp
        libAACenc/src/sf_estim.h

   - Revise TNS module to improve ELD audio quality.
   - Use new window function and separate prediction gain according TNS filters.
   - Add missing memory initilization to TNS configuration.
     Modified file(s):
        libAACenc/src/aacenc_lib.cpp
        libAACenc/src/aacenc_tns.cpp
        libAACenc/src/aacenc_tns.h
        libAACenc/src/psy_main.cpp
        libAACenc/src/tns_func.h

* SBR-Encoder

   - Revise frequency resolution calculation and handle differently depending
     on number of envelopes and split frames decision.
   - Add and adjust ELD SBR tuning tables.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/fram_gen.h
        libSBRenc/src/mh_det.cpp
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/sbr_rom.cpp
        libSBRenc/src/tran_det.cpp

   - Replace ELD transient detector with fast implementation.
     Modified file(s):
        libSBRenc/src/env_est.cpp
        libSBRenc/src/env_est.h
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

* FDK-Library
   - Introduce generic compare function in tools library.
     Modified file(s):
        libFDK/include/fixpoint_math.h
        libFDK/src/FDK_core.cpp

* SBR-Encoder

  -  Revise ELD frame splitter to improve bit distribution.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/fram_gen.cpp
        libSBRenc/src/fram_gen.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

   - Configure amplitude resolution according the tonality of the audio signal.
     Modified file(s):
        libSBRenc/include/sbr_encoder.h
        libSBRenc/src/bit_sbr.h
        libSBRenc/src/env_est.cpp
        libSBRenc/src/nf_est.cpp
        libSBRenc/src/nf_est.h
        libSBRenc/src/sbr_def.h
        libSBRenc/src/sbr_encoder.cpp
        libSBRenc/src/ton_corr.cpp
        libSBRenc/src/ton_corr.h
        libSBRenc/src/tran_det.cpp
        libSBRenc/src/tran_det.h

Change-Id: Ie0672b989a06ee63b50240616b8d1d4b790b6cb2

16 files changed, 895 insertions, 158 deletions

diff --git a/libSBRenc/include/sbr_encoder.h b/libSBRenc/include/sbr_encoder.h
index 93dc46d..aec0398 100644
--- a/libSBRenc/include/sbr_encoder.h
+++ b/libSBRenc/include/sbr_encoder.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -135,6 +135,12 @@ enum
   SBR_SYNTAX_DRM_CRC   = 0x0008
 };
 
+typedef enum
+{
+  FREQ_RES_LOW = 0,
+  FREQ_RES_HIGH
+} FREQ_RES;
+
 typedef struct
 {
   CODEC_TYPE       coreCoder;        /*!< LC or ELD */
@@ -168,8 +174,9 @@ typedef struct sbrConfiguration
   INT dynBwSupported;         /*!< Flag: support for dynamic bandwidth in this combination. */
   INT parametricCoding;       /*!< Flag: usage of parametric coding tool. */
   INT downSampleFactor;       /*!< Sampling rate relation between the SBR and the core encoder. */
-  int freq_res_fixfix[3];     /*!< Frequency resolution of envelopes in frame class FIXFIX
-                                 0=1 Env; 1=2 Env; 2=4 Env; */
+  FREQ_RES freq_res_fixfix[2];/*!< Frequency resolution of envelopes in frame class FIXFIX, for non-split case and split case */
+  UCHAR fResTransIsLow;       /*!< Frequency resolution of envelopes in transient frames: low (0) or variable (1) */
+
   /*
      core coder dependent tuning parameters
   */
@@ -221,6 +228,8 @@ typedef struct sbrConfiguration
   INT sbr_interpol_freq;      /*!< Flag: use interpolation in freq. direction. */
   INT sbr_smoothing_length;   /*!< Flag: choose length 4 or 0 (=on, off). */
   UCHAR init_amp_res_FF;
+  FIXP_DBL threshold_AmpRes_FF_m;
+  SCHAR threshold_AmpRes_FF_e;
 } sbrConfiguration, *sbrConfigurationPtr ;
 
 typedef struct SBR_CONFIG_DATA
@@ -237,7 +246,7 @@ typedef struct SBR_CONFIG_DATA
   INT noQmfBands;                       /**< Number of QMF frequency bands. */
   INT noQmfSlots;                       /**< Number of QMF slots. */
 
-  UCHAR *freqBandTable[2];              /**< Frequency table for low and hires, only MAX_FREQ_COEFFS/2 +1 coeefs actually needed for lowres. */
+  UCHAR *freqBandTable[2];              /**< Frequency table for low and hires, only MAX_FREQ_COEFFS/2 +1 coeffs actually needed for lowres. */
   UCHAR *v_k_master;                    /**< Master BandTable where freqBandTable is derived from. */
 
 
@@ -249,6 +258,8 @@ typedef struct SBR_CONFIG_DATA
   INT xposCtrlSwitch;                   /**< Flag indicates whether to switch xpos ctrl on the fly. */
   INT switchTransposers;                /**< Flag indicates whether to switch xpos on the fly .     */
   UCHAR initAmpResFF;
+  FIXP_DBL thresholdAmpResFF_m;
+  SCHAR thresholdAmpResFF_e;
 } SBR_CONFIG_DATA, *HANDLE_SBR_CONFIG_DATA;
 
 typedef struct {
diff --git a/libSBRenc/src/bit_sbr.h b/libSBRenc/src/bit_sbr.h
index 1ce2c1e..de4ac89 100644
--- a/libSBRenc/src/bit_sbr.h
+++ b/libSBRenc/src/bit_sbr.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -141,8 +141,8 @@ struct SBR_ENV_DATA
 {
 
   INT sbr_xpos_ctrl;
-  INT freq_res_fixfix;
-
+  FREQ_RES freq_res_fixfix[2];
+  UCHAR fResTransIsLow;
 
   INVF_MODE sbr_invf_mode;
   INVF_MODE sbr_invf_mode_vec[MAX_NUM_NOISE_VALUES];
@@ -205,6 +205,8 @@ struct SBR_ENV_DATA
   INT balance;
   AMP_RES init_sbr_amp_res;
   AMP_RES currentAmpResFF;
+  FIXP_DBL ton_HF[SBR_GLOBAL_TONALITY_VALUES]; /* tonality is scaled by 2^19/0.524288f (fract part of RELAXATION) */
+  FIXP_DBL global_tonality;
 
   /* extended data */
   INT extended_data;
diff --git a/libSBRenc/src/env_est.cpp b/libSBRenc/src/env_est.cpp
index 929f229..4fcda51 100644
--- a/libSBRenc/src/env_est.cpp
+++ b/libSBRenc/src/env_est.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -103,6 +103,114 @@ static const UCHAR panTable[2][10] = { { 0, 2, 4, 6, 8,12,16,20,24},
 static const UCHAR maxIndex[2] = {9, 5};
 
 
+/******************************************************************************
+ Functionname:  FDKsbrEnc_GetTonality
+******************************************************************************/
+/***************************************************************************/
+/*!
+
+  \brief      Calculates complete energy per band from the energy values
+              of the QMF subsamples.
+
+  \brief      quotaMatrix - calculated in FDKsbrEnc_CalculateTonalityQuotas()
+  \brief      noEstPerFrame - number of estimations per frame
+  \brief      startIndex - start index for the quota matrix
+  \brief      Energies - energy matrix
+  \brief      startBand - start band
+  \brief      stopBand - number of QMF bands
+  \brief      numberCols - number of QMF subsamples
+
+  \return     mean tonality of the 5 bands with the highest energy
+              scaled by 2^(RELAXATION_SHIFT+2)*RELAXATION_FRACT
+
+****************************************************************************/
+static FIXP_DBL FDKsbrEnc_GetTonality(
+        const FIXP_DBL *const *quotaMatrix,
+        const INT              noEstPerFrame,
+        const INT              startIndex,
+        const FIXP_DBL *const *Energies,
+        const UCHAR            startBand,
+        const INT              stopBand,
+        const INT              numberCols
+        )
+{
+  UCHAR b, e, k;
+  INT      no_enMaxBand[SBR_MAX_ENERGY_VALUES] = { -1, -1, -1, -1, -1 };
+  FIXP_DBL energyMax[SBR_MAX_ENERGY_VALUES] = { FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f) };
+  FIXP_DBL energyMaxMin = MAXVAL_DBL; /* min. energy in energyMax array */
+  UCHAR    posEnergyMaxMin = 0;       /* min. energy in energyMax array position */
+  FIXP_DBL tonalityBand[SBR_MAX_ENERGY_VALUES] = { FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(0.0f) };
+  FIXP_DBL globalTonality = FL2FXCONST_DBL(0.0f);
+  FIXP_DBL energyBand[QMF_CHANNELS];
+  INT      maxNEnergyValues; /* max. number of max. energy values */
+
+  /*** Sum up energies for each band ***/
+  FDK_ASSERT(numberCols==15||numberCols==16);
+  /* numberCols is always 15 or 16 for ELD. In case of 16 bands, the
+      energyBands are initialized with the [15]th column.
+      The rest of the column energies are added in the next step.   */
+  if (numberCols==15) {
+    for (b=startBand; b<stopBand; b++) {
+      energyBand[b]=FL2FXCONST_DBL(0.0f);
+    }
+  } else {
+    for (b=startBand; b<stopBand; b++) {
+      energyBand[b]=Energies[15][b]>>4;
+    }
+  }
+
+  for (k=0; k<15; k++) {
+    for (b=startBand; b<stopBand; b++) {
+      energyBand[b] += Energies[k][b]>>4;
+    }
+  }
+
+  /*** Determine 5 highest band-energies ***/
+  maxNEnergyValues = fMin(SBR_MAX_ENERGY_VALUES, stopBand-startBand);
+
+  /* Get min. value in energyMax array */
+  energyMaxMin = energyMax[0] = energyBand[startBand];
+  no_enMaxBand[0] = startBand;
+  posEnergyMaxMin = 0;
+  for (k=1; k<maxNEnergyValues; k++) {
+    energyMax[k] = energyBand[startBand+k];
+    no_enMaxBand[k] = startBand+k;
+    if (energyMaxMin > energyMax[k]) {
+      energyMaxMin = energyMax[k];
+      posEnergyMaxMin = k;
+    }
+  }
+
+  for (b=startBand+maxNEnergyValues; b<stopBand; b++) {
+    if (energyBand[b] > energyMaxMin) {
+      energyMax[posEnergyMaxMin] = energyBand[b];
+      no_enMaxBand[posEnergyMaxMin] = b;
+
+      /* Again, get min. value in energyMax array */
+      energyMaxMin = energyMax[0];
+      posEnergyMaxMin = 0;
+      for (k=1; k<maxNEnergyValues; k++) {
+        if (energyMaxMin > energyMax[k]) {
+          energyMaxMin = energyMax[k];
+          posEnergyMaxMin = k;
+        }
+      }
+    }
+  }
+  /*** End determine 5 highest band-energies ***/
+
+  /* Get tonality values for 5 highest energies */
+  for (e=0; e<maxNEnergyValues; e++) {
+    tonalityBand[e]=FL2FXCONST_DBL(0.0f);
+    for (k=0; k<noEstPerFrame; k++) {
+      tonalityBand[e] += quotaMatrix[startIndex + k][no_enMaxBand[e]] >> 1;
+    }
+    globalTonality += tonalityBand[e] >> 2; /* headroom of 2+1 (max. 5 additions) */
+  }
+
+  return globalTonality;
+}
+
 /***************************************************************************/
 /*!
 
@@ -919,10 +1027,42 @@ FDKsbrEnc_extractSbrEnvelope1 (
                                      hEnvChan->qmfScale);
 
 
+  if(h_con->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) {
+    FIXP_DBL tonality = FDKsbrEnc_GetTonality (
+          hEnvChan->TonCorr.quotaMatrix,
+          hEnvChan->TonCorr.numberOfEstimatesPerFrame,
+          hEnvChan->TonCorr.startIndexMatrix,
+          sbrExtrEnv->YBuffer + sbrExtrEnv->YBufferWriteOffset,
+          h_con->freqBandTable[HI][0]+1,
+          h_con->noQmfBands,
+          sbrExtrEnv->no_cols
+        );
+
+    hEnvChan->encEnvData.ton_HF[1] = hEnvChan->encEnvData.ton_HF[0];
+    hEnvChan->encEnvData.ton_HF[0] = tonality;
+
+    /* tonality is scaled by 2^19/0.524288f (fract part of RELAXATION) */
+    hEnvChan->encEnvData.global_tonality = (hEnvChan->encEnvData.ton_HF[0]>>1) + (hEnvChan->encEnvData.ton_HF[1]>>1);
+  }
+
+
 
   /*
     Transient detection COEFF Transform OK
   */
+  if(h_con->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY)
+  {
+    FDKsbrEnc_fastTransientDetect(
+            &hEnvChan->sbrFastTransientDetector,
+             sbrExtrEnv->YBuffer,
+             sbrExtrEnv->YBufferScale,
+             sbrExtrEnv->YBufferWriteOffset,
+             eData->transient_info
+             );
+
+  }
+  else
+  {
   FDKsbrEnc_transientDetect(&hEnvChan->sbrTransientDetector,
                              sbrExtrEnv->YBuffer,
                              sbrExtrEnv->YBufferScale,
@@ -931,6 +1071,7 @@ FDKsbrEnc_extractSbrEnvelope1 (
                              sbrExtrEnv->YBufferSzShift,
                              sbrExtrEnv->time_step,
                              hEnvChan->SbrEnvFrame.frameMiddleSlot);
+  }
 
 
 
@@ -951,7 +1092,8 @@ FDKsbrEnc_extractSbrEnvelope1 (
                           sbrExtrEnv->YBufferSzShift,
                           h_con->nSfb[1],
                           sbrExtrEnv->time_step,
-                          sbrExtrEnv->no_cols);
+                          sbrExtrEnv->no_cols,
+                         &hEnvChan->encEnvData.global_tonality);
 
 
 }
@@ -1128,12 +1270,26 @@ FDKsbrEnc_extractSbrEnvelope2 (
         && ( ed->nEnvelopes == 1 ) )
    {
 
-     if (hEnvChan->encEnvData.ldGrid)
-       hEnvChan->encEnvData.currentAmpResFF = (AMP_RES)h_con->initAmpResFF;
-     else
+     if (h_con->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY)
+     {
+       /* Note: global_tonaliy_float_value == ((float)hEnvChan->encEnvData.global_tonality/((INT64)(1)<<(31-(19+2)))/0.524288*(2.0/3.0)));
+                threshold_float_value == ((float)h_con->thresholdAmpResFF_m/((INT64)(1)<<(31-(h_con->thresholdAmpResFF_e)))/0.524288*(2.0/3.0))); */
+       /* decision of SBR_AMP_RES */
+       if (fIsLessThan( /* global_tonality > threshold ? */
+             h_con->thresholdAmpResFF_m, h_con->thresholdAmpResFF_e,
+             hEnvChan->encEnvData.global_tonality, RELAXATION_SHIFT+2 )
+          )
+       {
+         hEnvChan->encEnvData.currentAmpResFF = SBR_AMP_RES_1_5;
+       }
+       else {
+         hEnvChan->encEnvData.currentAmpResFF = SBR_AMP_RES_3_0;
+       }
+     } else {
        hEnvChan->encEnvData.currentAmpResFF = SBR_AMP_RES_1_5;
+     }
 
-     if ( hEnvChan->encEnvData.currentAmpResFF != hEnvChan->encEnvData.init_sbr_amp_res) {
+      if ( hEnvChan->encEnvData.currentAmpResFF != hEnvChan->encEnvData.init_sbr_amp_res) {
 
         FDKsbrEnc_InitSbrHuffmanTables(&hEnvChan->encEnvData,
                                        &hEnvChan->sbrCodeEnvelope,
@@ -1172,7 +1328,12 @@ FDKsbrEnc_extractSbrEnvelope2 (
     }
 
     /* Low energy in low band fix */
-    if ( hEnvChan->sbrTransientDetector.prevLowBandEnergy < hEnvChan->sbrTransientDetector.prevHighBandEnergy && hEnvChan->sbrTransientDetector.prevHighBandEnergy > FL2FX_DBL(0.03))
+    if ( hEnvChan->sbrTransientDetector.prevLowBandEnergy < hEnvChan->sbrTransientDetector.prevHighBandEnergy
+      && hEnvChan->sbrTransientDetector.prevHighBandEnergy > FL2FX_DBL(0.03)
+      /* The fix needs the non-fast transient detector running.
+         It sets prevLowBandEnergy and prevHighBandEnergy.      */
+      && !(h_con->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY)
+      )
     {
       int i;
 
diff --git a/libSBRenc/src/env_est.h b/libSBRenc/src/env_est.h
index 5e632a4..e17a974 100644
--- a/libSBRenc/src/env_est.h
+++ b/libSBRenc/src/env_est.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -127,6 +127,7 @@ typedef SBR_EXTRACT_ENVELOPE *HANDLE_SBR_EXTRACT_ENVELOPE;
 
 struct ENV_CHANNEL
 {
+  FAST_TRAN_DETECTOR sbrFastTransientDetector;
   SBR_TRANSIENT_DETECTOR sbrTransientDetector;
   SBR_CODE_ENVELOPE sbrCodeEnvelope;
   SBR_CODE_ENVELOPE sbrCodeNoiseFloor;
diff --git a/libSBRenc/src/fram_gen.cpp b/libSBRenc/src/fram_gen.cpp
index 86c3c81..9a35111 100644
--- a/libSBRenc/src/fram_gen.cpp
+++ b/libSBRenc/src/fram_gen.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -266,7 +266,7 @@ static void calcCtrlSignal (HANDLE_SBR_GRID hSbrGrid, FRAME_CLASS frameClass,
 
 static void ctrlSignal2FrameInfo (HANDLE_SBR_GRID hSbrGrid,
                                   HANDLE_SBR_FRAME_INFO hFrameInfo,
-                                  INT freq_res_fixfix);
+                                  FREQ_RES *freq_res_fixfix);
 
 
 /* table for 8 time slot index */
@@ -341,8 +341,9 @@ static const FREQ_RES freqRes_table_16[16] = {
 static void generateFixFixOnly ( HANDLE_SBR_FRAME_INFO hSbrFrameInfo,
                                  HANDLE_SBR_GRID hSbrGrid,
                                  int tranPosInternal,
-                                 int numberTimeSlots
-                               );
+                                 int numberTimeSlots,
+                                 UCHAR fResTransIsLow
+                                 );
 
 
 /*!
@@ -402,11 +403,10 @@ FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
   const int *v_tuningFreq = v_tuning + 3;
 
   hSbrEnvFrame->v_tuningSegm = v_tuningSegm;
-  INT freq_res_fixfix = hSbrEnvFrame->freq_res_fixfix;
 
   if (ldGrid) {
     /* in case there was a transient at the very end of the previous frame, start with a transient envelope */
-    if(v_transient_info_pre[1] && (numberTimeSlots - v_transient_info_pre[0] < minFrameTranDistance)){
+    if ( !tranFlag && v_transient_info_pre[1] && (numberTimeSlots - v_transient_info_pre[0] < minFrameTranDistance) ){
       tranFlag = 1;
       tranPos  = 0;
     }
@@ -529,7 +529,8 @@ FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
       generateFixFixOnly ( &(hSbrEnvFrame->SbrFrameInfo),
                            &(hSbrEnvFrame->SbrGrid),
                            tranPosInternal,
-                           numberTimeSlots
+                           numberTimeSlots,
+                           hSbrEnvFrame->fResTransIsLow
                            );
 
       return &(hSbrEnvFrame->SbrFrameInfo);
@@ -677,7 +678,7 @@ FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
   ---------------------------------------------------------------------------*/
   ctrlSignal2FrameInfo (&hSbrEnvFrame->SbrGrid,
                         &hSbrEnvFrame->SbrFrameInfo,
-                        freq_res_fixfix);
+                         hSbrEnvFrame->freq_res_fixfix);
 
   return &hSbrEnvFrame->SbrFrameInfo;
 }
@@ -692,7 +693,8 @@ FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
 static void generateFixFixOnly ( HANDLE_SBR_FRAME_INFO hSbrFrameInfo,
                                  HANDLE_SBR_GRID hSbrGrid,
                                  int tranPosInternal,
-                                 int numberTimeSlots
+                                 int numberTimeSlots,
+                                 UCHAR fResTransIsLow
                                )
 {
   int nEnv, i, k=0, tranIdx;
@@ -727,8 +729,12 @@ static void generateFixFixOnly ( HANDLE_SBR_FRAME_INFO hSbrFrameInfo,
   /* adjust segment-frequency-resolution according to the segment-length */
   for (i=0; i<nEnv; i++){
     k = hSbrFrameInfo->borders[i+1] - hSbrFrameInfo->borders[i];
-    hSbrFrameInfo->freqRes[i] = freqResTable[k];
-    hSbrGrid->v_f[i] = freqResTable[k];
+    if (!fResTransIsLow)
+      hSbrFrameInfo->freqRes[i] = freqResTable[k];
+    else
+      hSbrFrameInfo->freqRes[i] = FREQ_RES_LOW;
+
+    hSbrGrid->v_f[i] = hSbrFrameInfo->freqRes[i];
   }
 
   hSbrFrameInfo->nEnvelopes = nEnv;
@@ -765,15 +771,16 @@ static void generateFixFixOnly ( HANDLE_SBR_FRAME_INFO hSbrFrameInfo,
 
 *******************************************************************************/
 void
-FDKsbrEnc_initFrameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME  hSbrEnvFrame,
-                          INT allowSpread,
-                          INT numEnvStatic,
-                          INT staticFraming,
-                          INT timeSlots,
-                          INT freq_res_fixfix
-                          ,int ldGrid
-                          )
-
+FDKsbrEnc_initFrameInfoGenerator (
+              HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
+              INT       allowSpread,
+              INT       numEnvStatic,
+              INT       staticFraming,
+              INT       timeSlots,
+        const FREQ_RES* freq_res_fixfix
+             ,UCHAR     fResTransIsLow,
+              INT       ldGrid
+        )
 {                               /* FH 00-06-26 */
 
   FDKmemclear(hSbrEnvFrame,sizeof(SBR_ENVELOPE_FRAME ));
@@ -786,7 +793,9 @@ FDKsbrEnc_initFrameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME  hSbrEnvFrame,
   hSbrEnvFrame->allowSpread = allowSpread;
   hSbrEnvFrame->numEnvStatic = numEnvStatic;
   hSbrEnvFrame->staticFraming = staticFraming;
-  hSbrEnvFrame->freq_res_fixfix = freq_res_fixfix;
+  hSbrEnvFrame->freq_res_fixfix[0] = freq_res_fixfix[0];
+  hSbrEnvFrame->freq_res_fixfix[1] = freq_res_fixfix[1];
+  hSbrEnvFrame->fResTransIsLow     = fResTransIsLow;
 
   hSbrEnvFrame->length_v_bord = 0;
   hSbrEnvFrame->length_v_bordFollow = 0;
@@ -804,6 +813,7 @@ FDKsbrEnc_initFrameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME  hSbrEnvFrame,
       hSbrEnvFrame->dmin = 2;
       hSbrEnvFrame->dmax = 16;
       hSbrEnvFrame->frameMiddleSlot = FRAME_MIDDLE_SLOT_512LD;
+      hSbrEnvFrame->SbrGrid.bufferFrameStart = 0;
   } else
   switch(timeSlots){
     case NUMBER_TIME_SLOTS_1920:
@@ -1862,19 +1872,28 @@ createDefFrameInfo(HANDLE_SBR_FRAME_INFO hSbrFrameInfo, INT nEnv, INT nTimeSlots
  Functionname:  ctrlSignal2FrameInfo
  *******************************************************************************
 
- Description: Calculates frame_info struct from control signal.
+ Description: Convert "clear-text" sbr_grid() to "frame info" used by the
+              envelope and noise floor estimators.
+              This is basically (except for "low level" calculations) the
+              bitstream decoder defined in the MPEG-4 standard, sub clause
+              4.6.18.3.3, Time / Frequency Grid.  See inline comments for
+              explanation of the shorten and noise border algorithms.
 
  Arguments:   hSbrGrid - source
               hSbrFrameInfo - destination
+              freq_res_fixfix - frequency resolution for FIXFIX frames
 
  Return:      void; hSbrFrameInfo contains the updated FRAME_INFO struct
 
 *******************************************************************************/
 static void
-ctrlSignal2FrameInfo (HANDLE_SBR_GRID hSbrGrid,
-                      HANDLE_SBR_FRAME_INFO hSbrFrameInfo,
-                      INT freq_res_fixfix)
+ctrlSignal2FrameInfo (
+        HANDLE_SBR_GRID        hSbrGrid,       /* input : the grid handle       */
+        HANDLE_SBR_FRAME_INFO  hSbrFrameInfo,  /* output: the frame info handle */
+        FREQ_RES              *freq_res_fixfix /* in/out: frequency resolution for FIXFIX frames */
+        )
 {
+  INT frameSplit = 0;
   INT nEnv = 0, border = 0, i, k, p /*?*/;
   INT *v_r = hSbrGrid->bs_rel_bord;
   INT *v_f = hSbrGrid->v_f;
@@ -1887,17 +1906,10 @@ ctrlSignal2FrameInfo (HANDLE_SBR_GRID hSbrGrid,
   case FIXFIX:
     createDefFrameInfo(hSbrFrameInfo, hSbrGrid->bs_num_env, numberTimeSlots);
 
-    /* At this point all frequency resolutions are set to FREQ_RES_HIGH, so
-     * only if freq_res_fixfix is set to FREQ_RES_LOW, they all have to be
-     * changed.
-     * snd */
-    if (freq_res_fixfix == FREQ_RES_LOW) {
-      for (i = 0; i < hSbrFrameInfo->nEnvelopes; i++) {
-        hSbrFrameInfo->freqRes[i] = FREQ_RES_LOW;
-      }
+    frameSplit = (hSbrFrameInfo->nEnvelopes > 1);
+    for (i = 0; i < hSbrFrameInfo->nEnvelopes; i++) {
+      hSbrGrid->v_f[i] = hSbrFrameInfo->freqRes[i] = freq_res_fixfix[frameSplit];
     }
-    /* ELD: store current frequency resolution */
-    hSbrGrid->v_f[0] = hSbrFrameInfo->freqRes[0];
     break;
 
   case FIXVAR:
diff --git a/libSBRenc/src/fram_gen.h b/libSBRenc/src/fram_gen.h
index 3769266..00473d4 100644
--- a/libSBRenc/src/fram_gen.h
+++ b/libSBRenc/src/fram_gen.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -89,6 +89,7 @@ amm-info@iis.fraunhofer.de
 #define _FRAM_GEN_H
 
 #include "sbr_def.h" /* for MAX_ENVELOPES and MAX_NOISE_ENVELOPES in struct FRAME_INFO and CODEC_TYPE */
+#include "sbr_encoder.h" /* for FREQ_RES */
 
 #define MAX_ENVELOPES_VARVAR MAX_ENVELOPES /*!< worst case number of envelopes in a VARVAR frame */
 #define MAX_ENVELOPES_FIXVAR_VARFIX 4 /*!< worst case number of envelopes in VARFIX and FIXVAR frames */
@@ -114,7 +115,7 @@ typedef enum {
 #define NUMBER_TIME_SLOTS_1920  15
 
 #define LD_PRETRAN_OFF           3
-#define FRAME_MIDDLE_SLOT_512LD  0
+#define FRAME_MIDDLE_SLOT_512LD  4
 #define NUMBER_TIME_SLOTS_512LD  8
 #define TRANSIENT_OFFSET_LD      0
 
@@ -248,9 +249,10 @@ typedef struct
   INT frameMiddleSlot;      /*!< transient detector offset in SBR timeslots */
 
   /* basic tuning parameters */
-  INT staticFraming;        /*!< 1: run static framing in time, i.e. exclusive use of bs_frame_class = FIXFIX */
-  INT numEnvStatic;         /*!< number of envelopes per frame for static framing */
-  INT freq_res_fixfix;      /*!< envelope frequency resolution to use for bs_frame_class = FIXFIX */
+  INT staticFraming;           /*!< 1: run static framing in time, i.e. exclusive use of bs_frame_class = FIXFIX */
+  INT numEnvStatic;            /*!< number of envelopes per frame for static framing */
+  FREQ_RES freq_res_fixfix[2]; /*!< envelope frequency resolution to use for bs_frame_class = FIXFIX; single env and split */
+  UCHAR fResTransIsLow;        /*!< frequency resolution for transient frames - always low (0) or according to table (1) */
 
   /* expert tuning parameters */
   const int *v_tuningSegm;  /*!< segment lengths to use around transient */
@@ -286,14 +288,16 @@ typedef SBR_ENVELOPE_FRAME *HANDLE_SBR_ENVELOPE_FRAME;
 
 
 void
-FDKsbrEnc_initFrameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME  hSbrEnvFrame,
-                          INT allowSpread,
-                          INT numEnvStatic,
-                          INT staticFraming,
-                          INT timeSlots,
-                          INT freq_res_fixfix
-                          ,int ldGrid
-                          );
+FDKsbrEnc_initFrameInfoGenerator (
+              HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
+              INT       allowSpread,
+              INT       numEnvStatic,
+              INT       staticFraming,
+              INT       timeSlots,
+        const FREQ_RES* freq_res_fixfix
+             ,UCHAR     fResTransIsLow,
+              INT       ldGrid
+        );
 
 HANDLE_SBR_FRAME_INFO
 FDKsbrEnc_frameInfoGenerator (HANDLE_SBR_ENVELOPE_FRAME hSbrEnvFrame,
diff --git a/libSBRenc/src/mh_det.cpp b/libSBRenc/src/mh_det.cpp
index 73d1b8b..bc80a15 100644
--- a/libSBRenc/src/mh_det.cpp
+++ b/libSBRenc/src/mh_det.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -663,10 +663,27 @@ static void transientCleanUp(FIXP_DBL **quotaBuffer,
 }
 
 
-/**************************************************************************/
+/*****************************************************************************/
 /*!
-  \brief     Do detection for one tonality estimate.
+  \brief     Detection for one tonality estimate.
+
+  This is the actual missing harmonics detection, using information from the
+  previous detection.
+
+  If a missing harmonic was detected (in a previous frame) due to too high
+  tonality differences, but there was not enough tonality difference in the
+  current frame, the detection algorithm still continues to trace the strongest
+  tone in the scalefactor band (assuming that this is the tone that is going to
+  be replaced in the decoder). This is done to avoid abrupt endings of sines
+  fading out (e.g. in the glockenspiel).
+
+  The function also tries to estimate where one sine is going to be replaced
+  with multiple sines (due to the patching). This is done by comparing the
+  tonality flatness measure of the original and the SBR signal.
 
+  The function also tries to estimate (for the scalefactor bands only
+  containing one qmf subband) when a strong tone in the original will be
+  replaced by a strong tone in the adjacent QMF subband.
 
   \return    none.
 
@@ -694,10 +711,10 @@ static void detection(FIXP_DBL *quotaBuffer,
   for(i=0;i<nSfb;i++){
 
     thresTemp = (guideVectors.guideVectorDiff[i] != FL2FXCONST_DBL(0.0f))
-                  ? fixMax(fMult(mhThresh.decayGuideDiff,guideVectors.guideVectorDiff[i]), mhThresh.thresHoldDiffGuide)
+                  ? fMax(fMult(mhThresh.decayGuideDiff,guideVectors.guideVectorDiff[i]), mhThresh.thresHoldDiffGuide)
                   : mhThresh.thresHoldDiff;
 
-    thresTemp = fixMin(thresTemp, mhThresh.thresHoldDiff);
+    thresTemp = fMin(thresTemp, mhThresh.thresHoldDiff);
 
     if(pDiffVecScfb[i] > thresTemp){
       pHarmVec[i] = 1;
@@ -813,8 +830,11 @@ static void detectionWithPrediction(FIXP_DBL **quotaBuffer,
 
   if(newDetectionAllowed){
 
+    /* Since we don't want to use the transient region for detection (since the tonality values
+       tend to be a bit unreliable for this region) the guide-values are copied to the current
+       starting point. */
     if(totNoEst > 1){
-      start = detectionStart;
+      start = detectionStart+1;
 
       if (start != 0) {
         FDKmemcpy(guideVectors[start].guideVectorDiff,guideVectors[0].guideVectorDiff,nSfb*sizeof(FIXP_DBL));
diff --git a/libSBRenc/src/nf_est.cpp b/libSBRenc/src/nf_est.cpp
index 385a043..a4c5574 100644
--- a/libSBRenc/src/nf_est.cpp
+++ b/libSBRenc/src/nf_est.cpp
@@ -298,7 +298,7 @@ FDKsbrEnc_sbrNoiseFloorEstimateQmf(HANDLE_SBR_NOISE_FLOOR_ESTIMATE h_sbrNoiseFlo
                          SCHAR    *indexVector,              /*!< Index vector to obtain the patched data. */
                          INT missingHarmonicsFlag,           /*!< Flag indicating if a strong tonal component will be missing. */
                          INT startIndex,                     /*!< Start index. */
-                         int numberOfEstimatesPerFrame,      /*!< The number of tonality estimates per frame. */
+                         UINT numberOfEstimatesPerFrame,     /*!< The number of tonality estimates per frame. */
                          int transientFrame,                 /*!< A flag indicating if a transient is present. */
                          INVF_MODE* pInvFiltLevels,          /*!< Pointer to the vector holding the inverse filtering levels. */
                          UINT sbrSyntaxFlags
diff --git a/libSBRenc/src/nf_est.h b/libSBRenc/src/nf_est.h
index d407274..f26f74f 100644
--- a/libSBRenc/src/nf_est.h
+++ b/libSBRenc/src/nf_est.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -119,7 +119,7 @@ FDKsbrEnc_sbrNoiseFloorEstimateQmf(HANDLE_SBR_NOISE_FLOOR_ESTIMATE h_sbrNoiseFlo
                          SCHAR* indexVector,                 /*!< Index vector to obtain the patched data. */
                          INT missingHarmonicsFlag,           /*!< Flag indicating if a strong tonal component will be missing. */
                          INT startIndex,                     /*!< Start index. */
-                         int numberOfEstimatesPerFrame,      /*!< The number of tonality estimates per frame. */
+                         UINT numberOfEstimatesPerFrame,     /*!< The number of tonality estimates per frame. */
                          INT transientFrame,                 /*!< A flag indicating if a transient is present. */
                          INVF_MODE* pInvFiltLevels,          /*!< Pointer to the vector holding the inverse filtering levels. */
                          UINT sbrSyntaxFlags
diff --git a/libSBRenc/src/sbr_def.h b/libSBRenc/src/sbr_def.h
index 8b7cfc6..85ac587 100644
--- a/libSBRenc/src/sbr_def.h
+++ b/libSBRenc/src/sbr_def.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -122,6 +122,8 @@ amm-info@iis.fraunhofer.de
 /************  Definitions ***************/
 #define SBR_COMP_MODE_DELTA                     0
 #define SBR_COMP_MODE_CTS                       1
+#define SBR_MAX_ENERGY_VALUES                   5
+#define SBR_GLOBAL_TONALITY_VALUES              2
 
 #define MAX_NUM_CHANNELS                        2
 
@@ -232,6 +234,8 @@ amm-info@iis.fraunhofer.de
 #define FREQ                      0
 #define TIME                      1
 
+/* qmf data scaling */
+#define QMF_SCALE_OFFSET          7
 
 /* huffman tables */
 #define CODE_BOOK_SCF_LAV00         60
@@ -268,12 +272,4 @@ typedef enum
 }
 INVF_MODE;
 
-typedef enum
-{
-  FREQ_RES_LOW = 0,
-  FREQ_RES_HIGH
-}
-FREQ_RES;
-
-
 #endif
diff --git a/libSBRenc/src/sbr_encoder.cpp b/libSBRenc/src/sbr_encoder.cpp
index 9bb98c8..90b19cf 100644
--- a/libSBRenc/src/sbr_encoder.cpp
+++ b/libSBRenc/src/sbr_encoder.cpp
@@ -103,7 +103,7 @@ amm-info@iis.fraunhofer.de
 
 #define SBRENCODER_LIB_VL0 3
 #define SBRENCODER_LIB_VL1 3
-#define SBRENCODER_LIB_VL2 8
+#define SBRENCODER_LIB_VL2 12
 
 
 
@@ -412,6 +412,23 @@ FDKsbrEnc_AdjustSbrSettings (const sbrConfigurationPtr config, /*! output, modif
   config->codecSettings.transFac        = transFac;
   config->codecSettings.standardBitrate = standardBitrate;
 
+  if (bitRate < 28000) {
+    config->threshold_AmpRes_FF_m = (FIXP_DBL)MAXVAL_DBL;
+    config->threshold_AmpRes_FF_e = 7;
+  }
+  else if (bitRate >= 28000 && bitRate <= 48000) {
+    /* The float threshold is 75
+       0.524288f is fractional part of RELAXATION, the quotaMatrix and therefore tonality are scaled by this
+       2/3 is because the original implementation divides the tonality values by 3, here it's divided by 2
+       128 compensates the necessary shiftfactor of 7 */
+    config->threshold_AmpRes_FF_m = FL2FXCONST_DBL(75.0f*0.524288f/(2.0f/3.0f)/128.0f);
+    config->threshold_AmpRes_FF_e = 7;
+  }
+  else if (bitRate > 48000) {
+    config->threshold_AmpRes_FF_m = FL2FXCONST_DBL(0);
+    config->threshold_AmpRes_FF_e = 0;
+  }
+
   if (bitRate==0) {
     /* map vbr quality to bitrate */
     if (vbrMode < 30)
@@ -467,6 +484,57 @@ FDKsbrEnc_AdjustSbrSettings (const sbrConfigurationPtr config, /*! output, modif
     config->stereoMode      = sbrTuningTable[idx].stereoMode ;
     config->freqScale       = sbrTuningTable[idx].freqScale ;
 
+    if (numChannels == 1) {
+      /* stereo case */
+      switch (core) {
+        case AOT_AAC_LC:
+          if (bitRate <= (useSpeechConfig?24000U:20000U)) {
+            config->freq_res_fixfix[0] = FREQ_RES_LOW; /* set low frequency resolution for non-split frames */
+            config->freq_res_fixfix[1] = FREQ_RES_LOW; /* set low frequency resolution for split frames */
+          }
+          break;
+        case AOT_ER_AAC_ELD:
+          if (bitRate < 36000)
+            config->freq_res_fixfix[1] = FREQ_RES_LOW; /* set low frequency resolution for split frames */
+          if (bitRate < 26000) {
+            config->freq_res_fixfix[0] = FREQ_RES_LOW; /* set low frequency resolution for non-split frames */
+            config->fResTransIsLow = 1;                /* for transient frames, set low frequency resolution */
+          }
+          break;
+        default:
+          break;
+      }
+    }
+    else {
+      /* stereo case */
+      switch (core) {
+        case AOT_AAC_LC:
+          if (bitRate <= 28000) {
+            config->freq_res_fixfix[0] = FREQ_RES_LOW; /* set low frequency resolution for non-split frames */
+            config->freq_res_fixfix[1] = FREQ_RES_LOW; /* set low frequency resolution for split frames */
+          }
+          break;
+        case AOT_ER_AAC_ELD:
+          if (bitRate < 72000) {
+            config->freq_res_fixfix[1] = FREQ_RES_LOW; /* set low frequency resolution for split frames */
+          }
+          if (bitRate < 52000) {
+            config->freq_res_fixfix[0] = FREQ_RES_LOW; /* set low frequency resolution for non-split frames */
+            config->fResTransIsLow = 1;                /* for transient frames, set low frequency resolution */
+          }
+          break;
+        default:
+          break;
+      }
+      if (bitRate <= 28000) {
+        /*
+          additionally restrict frequency resolution in FIXFIX frames
+          to further reduce SBR payload size */
+        config->freq_res_fixfix[0] = FREQ_RES_LOW;
+        config->freq_res_fixfix[1] = FREQ_RES_LOW;
+      }
+    }
+
     /* adjust usage of parametric coding dependent on bitrate and speech config flag */
     if (useSpeechConfig)
       config->parametricCoding  = 0;
@@ -515,6 +583,7 @@ static UINT
 FDKsbrEnc_InitializeSbrDefaults (sbrConfigurationPtr config,
                                  INT                 downSampleFactor,
                                  UINT                codecGranuleLen
+                                ,const INT           isLowDelay
                                  )
 {
     if ( (downSampleFactor < 1 || downSampleFactor > 2) ||
@@ -525,7 +594,11 @@ FDKsbrEnc_InitializeSbrDefaults (sbrConfigurationPtr config,
     config->useWaveCoding          = 0;
     config->crcSbr                 = 0;
     config->dynBwSupported         = 1;
-    config->tran_thr               = 13000;
+    if (isLowDelay)
+      config->tran_thr             = 6000;
+    else
+      config->tran_thr             = 13000;
+
     config->parametricCoding       = 1;
 
     config->sbrFrameSize           = codecGranuleLen * downSampleFactor;
@@ -558,7 +631,9 @@ FDKsbrEnc_InitializeSbrDefaults (sbrConfigurationPtr config,
     config->noiseFloorOffset       = 0;
     config->startFreq              = 5; /*  5.9 respectively  6.0 kHz at fs = 44.1/48 kHz */
     config->stopFreq               = 9; /* 16.2 respectively 16.8 kHz at fs = 44.1/48 kHz */
-
+    config->freq_res_fixfix[0]     = FREQ_RES_HIGH;  /* non-split case */
+    config->freq_res_fixfix[1]     = FREQ_RES_HIGH;  /* split case */
+    config->fResTransIsLow = 0;  /* for transient frames, set variable frequency resolution according to freqResTable */
 
     /* header_extra_1 */
     config->freqScale       = SBR_FREQ_SCALE_DEFAULT;
@@ -1206,7 +1281,10 @@ initEnvChannel (  HANDLE_SBR_CONFIG_DATA sbrConfigData,
 
   FDK_ASSERT(params->e >= 0);
 
-  hEnv->encEnvData.freq_res_fixfix = 1;
+  hEnv->encEnvData.freq_res_fixfix[0] = params->freq_res_fixfix[0];
+  hEnv->encEnvData.freq_res_fixfix[1] = params->freq_res_fixfix[1];
+  hEnv->encEnvData.fResTransIsLow     = params->fResTransIsLow;
+
   hEnv->fLevelProtect = 0;
 
   hEnv->encEnvData.ldGrid = (sbrConfigData->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) ? 1 : 0;
@@ -1348,11 +1426,29 @@ initEnvChannel (  HANDLE_SBR_CONFIG_DATA sbrConfigData,
                             e,
                             params->stat,
                             timeSlots,
-                            hEnv->encEnvData.freq_res_fixfix
-                            ,hEnv->encEnvData.ldGrid
+                            hEnv->encEnvData.freq_res_fixfix,
+                            hEnv->encEnvData.fResTransIsLow,
+                            hEnv->encEnvData.ldGrid
                             );
 
+  if(sbrConfigData->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY)
+  {
+    INT bandwidth_qmf_slot = (sbrConfigData->sampleFreq>>1) / (sbrConfigData->noQmfBands);
+    if(FDKsbrEnc_InitSbrFastTransientDetector(
+              &hEnv->sbrFastTransientDetector,
+               sbrConfigData->noQmfSlots,
+               bandwidth_qmf_slot,
+               sbrConfigData->noQmfBands,
+               sbrConfigData->freqBandTable[0][0]
+               ))
+      return(1);
+  }
+
+  /* The transient detector has to be initialized also if the fast transient
+     detector was active, because the values from the transient detector
+     structure are used. */
   if(FDKsbrEnc_InitSbrTransientDetector (&hEnv->sbrTransientDetector,
+                                          sbrConfigData->sbrSyntaxFlags,
                                           sbrConfigData->frameSize,
                                           sbrConfigData->sampleFreq,
                                           params,
@@ -1658,6 +1754,8 @@ INT FDKsbrEnc_EnvInit (
    /* other switches */
   hSbrElement->sbrConfigData.useWaveCoding             = params->useWaveCoding;
   hSbrElement->sbrConfigData.useParametricCoding       = params->parametricCoding;
+  hSbrElement->sbrConfigData.thresholdAmpResFF_m       = params->threshold_AmpRes_FF_m;
+  hSbrElement->sbrConfigData.thresholdAmpResFF_e       = params->threshold_AmpRes_FF_e;
 
   /* init freq band table */
   if(updateFreqBandTable(&hSbrElement->sbrConfigData,
@@ -1999,7 +2097,8 @@ INT sbrEncoder_Init(
          */
         if ( ! FDKsbrEnc_InitializeSbrDefaults ( &sbrConfig[el],
                                                  *downSampleFactor,
-                                                  coreFrameLength
+                                                  coreFrameLength,
+                                                  IS_LOWDELAY(aot)
                                                   ) )
         {
           error = 1;
diff --git a/libSBRenc/src/sbr_rom.cpp b/libSBRenc/src/sbr_rom.cpp
index a2b6527..7a51668 100644
--- a/libSBRenc/src/sbr_rom.cpp
+++ b/libSBRenc/src/sbr_rom.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -684,6 +684,9 @@ const sbrTuningTable_t sbrTuningTable[] =
 
   /** AAC LOW DELAY SECTION **/
 
+  /* 24 kHz dual rate - 12kHz singlerate is not allowed (deactivated in FDKsbrEnc_IsSbrSettingAvail()) */
+  { CODEC_AACLD,   8000, 32000,  12000, 1,  1, 1, 0, 0,  1, 0, 6, SBR_MONO, 3 }, /* nominal:  8 kbit/s */
+
   /*** mono ***/
   /* 16/32 kHz dual rate not yet tuned ->alb copied from non LD tables*/
   { CODEC_AACLD,  16000, 18000,  16000, 1,  4, 5, 9, 7,  1, 0, 6, SBR_MONO, 3 }, /* nominal: 16 kbit/s wrr: tuned */
@@ -702,10 +705,10 @@ const sbrTuningTable_t sbrTuningTable[] =
   { CODEC_AACLD,  52000, 64001,  22050, 1, 13,11,11,10,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 56 kbit/s */
 
   /* 24/48 kHz dual rate */
-  { CODEC_AACLD,  20000, 22000,  24000, 1,  4, 1, 8, 4,  2, 3, 6, SBR_MONO, 2 }, /* nominal: 20 kbit/s */
+  { CODEC_AACLD,  20000, 22000,  24000, 1,  3, 4, 8, 8,  2, 0, 6, SBR_MONO, 2 }, /* nominal: 20 kbit/s */
   { CODEC_AACLD,  22000, 28000,  24000, 1,  3, 8, 8, 7,  2, 0, 3, SBR_MONO, 2 }, /* nominal: 24 kbit/s */
   { CODEC_AACLD,  28000, 36000,  24000, 1,  4, 8, 8, 7,  2, 0, 3, SBR_MONO, 2 }, /* nominal: 32 kbit/s */
-  { CODEC_AACLD,  36000, 56000,  24000, 1,  8, 9, 9, 9,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 40 kbit/s */
+  { CODEC_AACLD,  36000, 56000,  24000, 1,  8, 9, 9, 8,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 40 kbit/s */
   { CODEC_AACLD,  56000, 64001,  24000, 1, 13,11,11,10,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 64 kbit/s */
 
   /* 32/64 kHz dual rate */  /* placebo settings */  /*jgr: new, copy from CODEC_AAC */
@@ -722,7 +725,7 @@ const sbrTuningTable_t sbrTuningTable[] =
   { CODEC_AACLD, 100000,160001,  44100, 1, 13,13,11,11,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 128 */
 
   /* 48/96 kHz dual rate */  /* 32 and 40kbps line tuned for dual-rate SBR */
-  { CODEC_AACLD,  36000, 60000,  48000, 1,  8, 7, 6, 9,  2, 0, 3, SBR_MONO, 2 }, /* nominal: 40 */
+  { CODEC_AACLD,  36000, 60000,  48000, 1,  4, 7, 4, 4,  2, 0, 3, SBR_MONO, 3 }, /* nominal: 40 */
   { CODEC_AACLD,  60000, 72000,  48000, 1,  9, 9,10,10,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 64 */
   { CODEC_AACLD,  72000,100000,  48000, 1, 11,11,11,11,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 80 */
   { CODEC_AACLD, 100000,160001,  48000, 1, 13,13,11,11,  2, 0, 3, SBR_MONO, 1 }, /* nominal: 128 */
diff --git a/libSBRenc/src/ton_corr.cpp b/libSBRenc/src/ton_corr.cpp
index 224da11..af5afba 100644
--- a/libSBRenc/src/ton_corr.cpp
+++ b/libSBRenc/src/ton_corr.cpp
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -682,7 +682,7 @@ FDKsbrEnc_InitTonCorrParamExtr (INT frameSize,                     /*!< Current
 
   /*
   Reset the patching and allocate memory for the quota matrix.
-  Assing parameters for the LPC analysis.
+  Assuming parameters for the LPC analysis.
   */
   if (sbrCfg->sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) {
     switch (timeSlots) {
@@ -690,7 +690,7 @@ FDKsbrEnc_InitTonCorrParamExtr (INT frameSize,                     /*!< Current
       hTonCorr->lpcLength[0]              = 8 - LPC_ORDER;
       hTonCorr->lpcLength[1]              = 7 - LPC_ORDER;
       hTonCorr->numberOfEstimates         = NO_OF_ESTIMATES_LD;
-      hTonCorr->numberOfEstimatesPerFrame = sbrCfg->noQmfSlots / 7;
+      hTonCorr->numberOfEstimatesPerFrame = 2; /* sbrCfg->noQmfSlots / 7 */
       hTonCorr->frameStartIndexInvfEst    = 0;
       hTonCorr->transientPosOffset        = FRAME_MIDDLE_SLOT_512LD;
       break;
@@ -698,7 +698,7 @@ FDKsbrEnc_InitTonCorrParamExtr (INT frameSize,                     /*!< Current
       hTonCorr->lpcLength[0]              = 8 - LPC_ORDER;
       hTonCorr->lpcLength[1]              = 8 - LPC_ORDER;
       hTonCorr->numberOfEstimates         = NO_OF_ESTIMATES_LD;
-      hTonCorr->numberOfEstimatesPerFrame = sbrCfg->noQmfSlots / 8;
+      hTonCorr->numberOfEstimatesPerFrame = 2; /* sbrCfg->noQmfSlots / 8 */
       hTonCorr->frameStartIndexInvfEst    = 0;
       hTonCorr->transientPosOffset        = FRAME_MIDDLE_SLOT_512LD;
       break;
diff --git a/libSBRenc/src/ton_corr.h b/libSBRenc/src/ton_corr.h
index 8c8425c..504ab03 100644
--- a/libSBRenc/src/ton_corr.h
+++ b/libSBRenc/src/ton_corr.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -118,7 +118,7 @@ typedef struct
   INT bufferLength;               /*!< Length of the r and i buffers. */
   INT stepSize;                   /*!< Stride for the lpc estimate. */
   INT numberOfEstimates;          /*!< The total number of estiamtes, available in the quotaMatrix.*/
-  INT numberOfEstimatesPerFrame;  /*!< The number of estimates per frame available in the quotaMatrix.*/
+  UINT numberOfEstimatesPerFrame; /*!< The number of estimates per frame available in the quotaMatrix.*/
   INT lpcLength[2];               /*!< Segment length used for second order LPC analysis.*/
   INT nextSample;                 /*!< Where to start the LPC analysis of the current frame.*/
   INT move;                       /*!< How many estimates to move in the quotaMatrix, when buffering. */
diff --git a/libSBRenc/src/tran_det.cpp b/libSBRenc/src/tran_det.cpp
index 6c62b4c..33ea60e 100644
--- a/libSBRenc/src/tran_det.cpp
+++ b/libSBRenc/src/tran_det.cpp
@@ -89,7 +89,7 @@ amm-info@iis.fraunhofer.de
 
 #include "genericStds.h"
 
-#define NORM_QMF_ENERGY 5.684341886080801486968994140625e-14 /* 2^-44 */
+#define NORM_QMF_ENERGY 9.31322574615479E-10 /* 2^-30 */
 
 /* 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)
@@ -106,22 +106,30 @@ amm-info@iis.fraunhofer.de
 
  \return  calculated value
 *******************************************************************************/
+#define NRG_SHIFT  3 /* for energy summation */
+
 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 YBufferWriteOffset,
+                               INT stop,
+                               INT *result_e)
 {
   INT i,j;
   INT len1,len2;
-  FIXP_DBL delta,tmp0,tmp1,tmp2;
-  FIXP_DBL accu1,accu2,delta_sum,result;
+  SCHAR energies_e_diff[NUMBER_TIME_SLOTS_2304], energies_e, energyTotal_e=19, energies_e_add;
+  SCHAR prevEnergies_e_diff, newEnergies_e_diff;
+  FIXP_DBL tmp0,tmp1;
+  FIXP_DBL accu1,accu2,accu1_init,accu2_init;
+  FIXP_DBL delta, delta_sum;
+  INT accu_e, tmp_e;
 
-  FDK_ASSERT(scaleEnergies[0] >= 0);
+  delta_sum = FL2FXCONST_DBL(0.0f);
+  *result_e = 0;
 
-  /* equal for aac (would be not equal for mp3) */
   len1 = border-start;
   len2 = stop-border;
 
@@ -130,43 +138,91 @@ static FIXP_DBL spectralChange(FIXP_DBL Energies[NUMBER_TIME_SLOTS_2304][MAX_FRE
   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);
+  /*** Calc scaling for energies ***/
+  FDK_ASSERT(scaleEnergies[0] >= 0);
+  FDK_ASSERT(scaleEnergies[1] >= 0);
+
+  energies_e = 19 - FDKmin(scaleEnergies[0], scaleEnergies[1]);
+
+  /* limit shift for energy accumulation, energies_e can be -10 min. */
+  if (energies_e < -10) {
+     energies_e_add = -10 - energies_e;
+     energies_e = -10;
+  } else if (energies_e > 17) {
+     energies_e_add = energies_e - 17;
+     energies_e = 17;
+  } else {
+     energies_e_add = 0;
+  }
+
+  /* compensate scaling differences between scaleEnergies[0] and scaleEnergies[1]  */
+  prevEnergies_e_diff = scaleEnergies[0] - FDKmin(scaleEnergies[0], scaleEnergies[1]) + energies_e_add + NRG_SHIFT;
+  newEnergies_e_diff  = scaleEnergies[1] - FDKmin(scaleEnergies[0], scaleEnergies[1]) + energies_e_add + NRG_SHIFT;
+
+  prevEnergies_e_diff = fMin(prevEnergies_e_diff, DFRACT_BITS-1);
+  newEnergies_e_diff  = fMin(newEnergies_e_diff,  DFRACT_BITS-1);
+
+  for (i=start; i<YBufferWriteOffset; i++) {
+    energies_e_diff[i] = prevEnergies_e_diff;
+  }
+  for (i=YBufferWriteOffset; i<stop; i++) {
+    energies_e_diff[i] = newEnergies_e_diff;
+  }
 
   /* Sum up energies of all QMF-timeslots for both halfs */
+  FDK_ASSERT(len1<=8); /* otherwise an overflow is possible */
+  FDK_ASSERT(len2<=8); /* otherwise an overflow is possible */
+  /* init with some energy to prevent division by zero
+      and to prevent splitting for very low levels */
+  accu1_init = scaleValue((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY))),-energies_e);
+  accu2_init = scaleValue((FL2FXCONST_DBL((1.0e6*NORM_QMF_ENERGY))),-energies_e);
+  accu1_init = fMult(accu1_init, (FIXP_DBL)len1<<((DFRACT_BITS-1)-NRG_SHIFT-1))<<1;
+  accu2_init = fMult(accu2_init, (FIXP_DBL)len2<<((DFRACT_BITS-1)-NRG_SHIFT-1))<<1;
+
   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 */
+
+    accu1 = accu1_init;
+    accu2 = accu2_init;
+    accu_e = energies_e+3;
 
     /* Sum up energies in first half */
     for (i=start; i<border; i++) {
-      accu1 += (Energies[i][j]>>NRG_SCALE);
+      accu1 += scaleValue(Energies[i][j], -energies_e_diff[i]);
     }
 
     /* Sum up energies in second half */
     for (i=border; i<stop; i++) {
-      accu2 += (Energies[i][j]>>NRG_SCALE);
+      accu2 += scaleValue(Energies[i][j], -energies_e_diff[i]);
     }
 
     /* 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)));
+    #define LN2 FL2FXCONST_DBL(0.6931471806f) /* ln(2) */
+    tmp0 = fLog2(accu2, accu_e) - fLog2(accu1, accu_e);
+    tmp1 = fLog2((FIXP_DBL)len1, 31) - fLog2((FIXP_DBL)len2, 31);
+    delta = fMult(LN2, (tmp0 + tmp1));
+    delta = (FIXP_DBL)FDKabs( delta );
 
     /* 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)) );
+    accu_e++;
+    accu1>>=1;
+    accu2>>=1;
+    if (accu_e & 1) {
+      accu_e++;
+      accu1>>=1;
+      accu2>>=1;
+    }
 
-    delta_sum += (FIXP_DBL)(fMult(sqrtFixp(result), delta));
+    delta_sum += fMult(sqrtFixp(accu1+accu2), delta);
+    *result_e = ((accu_e>>1) + LD_DATA_SHIFT);
   }
 
+  energyTotal_e+=1; /* for a defined square result exponent, the exponent has to be even */
+  EnergyTotal<<=1;
+  delta_sum = fMult(delta_sum, invSqrtNorm2(EnergyTotal, &tmp_e));
+  *result_e = *result_e + (tmp_e-(energyTotal_e>>1));
+
   return fMult(delta_sum, pos_weight);
+
 }
 
 
@@ -175,9 +231,12 @@ static FIXP_DBL spectralChange(FIXP_DBL Energies[NUMBER_TIME_SLOTS_2304][MAX_FRE
  *******************************************************************************
  \brief   Calculates total lowband energy
 
- The return value nrgTotal is scaled by the factor (1/32.0)
+ The input values Energies[0] (low-band) are scaled by the factor
+ 2^(14-*scaleEnergies[0])
+ The input values Energies[1] (high-band) are scaled by the factor
+ 2^(14-*scaleEnergies[1])
 
- \return  total energy in the lowband
+ \return  total energy in the lowband, scaled by the factor 2^19
 *******************************************************************************/
 static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies,
                                    int       *scaleEnergies,
@@ -194,6 +253,7 @@ static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies,
   int ts,k;
 
   /* Sum up lowband energy from one frame at offset tran_off */
+  /* freqBandTable[LORES] has MAX_FREQ_COEFFS/2 +1 coeefs max. */
   for (ts=tran_offdiv2; ts<YBufferWriteOffset; ts++) {
     for (k = 0; k < freqBandTable[0]; k++) {
       accu1 += Energies[ts][k] >> 6;
@@ -201,12 +261,12 @@ static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies,
   }
   for (; ts<tran_offdiv2+(slots>>nrgSzShift); ts++) {
     for (k = 0; k < freqBandTable[0]; k++) {
-      accu2 += Energies[ts][k] >> 6;
+      accu2 += Energies[ts][k] >> 9;
     }
   }
 
-  nrgTotal = ( (accu1 >> fixMin(scaleEnergies[0],(DFRACT_BITS-1)))
-           +   (accu2 >> fixMin(scaleEnergies[1],(DFRACT_BITS-1))) ) << (2);
+  nrgTotal = ( scaleValueSaturate(accu1, 1-scaleEnergies[0]) )
+           + ( scaleValueSaturate(accu2, 4-scaleEnergies[1]) );
 
   return(nrgTotal);
 }
@@ -222,21 +282,23 @@ static FIXP_DBL addLowbandEnergies(FIXP_DBL **Energies,
  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)
+ The values EnergiesM are scaled by the factor (2^19-scaleEnergies[0]) for
+ slots<YBufferWriteOffset and by the factor (2^19-scaleEnergies[1]) for
+ slots>=YBufferWriteOffset.
 
- \return  total energy in the highband
+ \return  total energy in the highband, scaled by factor 2^19
 *******************************************************************************/
 
 static FIXP_DBL addHighbandEnergies(FIXP_DBL **RESTRICT Energies, /*!< input */
                                     INT       *scaleEnergies,
+                                    INT        YBufferWriteOffset,
                                     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 i,j,k,slotIn,slotOut,scale[2];
   INT li,ui;
   FIXP_DBL nrgTotal;
   FIXP_DBL accu = FL2FXCONST_DBL(0.0f);
@@ -245,7 +307,7 @@ static FIXP_DBL addHighbandEnergies(FIXP_DBL **RESTRICT Energies, /*!< input */
      combine QMF-bands to SBR-bands,
      combine Left and Right channel */
   for (slotOut=0; slotOut<sbrSlots; slotOut++) {
-    slotIn = 2*slotOut;
+    slotIn = timeStep*slotOut;
 
     for (j=0; j<nSfb; j++) {
       accu = FL2FXCONST_DBL(0.0f);
@@ -262,19 +324,29 @@ static FIXP_DBL addHighbandEnergies(FIXP_DBL **RESTRICT Energies, /*!< input */
     }
   }
 
-  scale = fixMin(8,scaleEnergies[0]);      /* scale energies down before add up */
+  /* scale energies down before add up */
+  scale[0] = fixMin(8,scaleEnergies[0]);
+  scale[1] = fixMin(8,scaleEnergies[1]);
 
-  if ((scaleEnergies[0]-1) > (DFRACT_BITS-1) )
+  if ((scaleEnergies[0]-scale[0]) > (DFRACT_BITS-1) || (scaleEnergies[1]-scale[0]) > (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 (slotOut=0; slotOut<YBufferWriteOffset; slotOut++) {
       for (j=0; j<nSfb; j++) {
-        accu += (EnergiesM[slotOut][j] >> scale);
+        accu += (EnergiesM[slotOut][j] >> scale[0]);
       }
     }
-    nrgTotal = accu >> (scaleEnergies[0]-scale);
+    nrgTotal = accu >> (scaleEnergies[0]-scale[0]);
+
+    for (slotOut=YBufferWriteOffset; slotOut<sbrSlots; slotOut++) {
+      for (j=0; j<nSfb; j++) {
+        accu += (EnergiesM[slotOut][j] >> scale[0]);
+      }
+    }
+    nrgTotal = accu >> (scaleEnergies[1]-scale[1]);
   }
 
   return(nrgTotal);
@@ -299,18 +371,23 @@ FDKsbrEnc_frameSplitter(FIXP_DBL **Energies,
                         int YBufferSzShift,
                         int nSfb,
                         int timeStep,
-                        int no_cols)
+                        int no_cols,
+                        FIXP_DBL* tonality)
 {
   if (tran_vector[1]==0) /* no transient was detected */
   {
     FIXP_DBL delta;
-    FIXP_DBL EnergiesM[NUMBER_TIME_SLOTS_2304][MAX_FREQ_COEFFS];
+    INT delta_e;
+    FIXP_DBL (*EnergiesM)[MAX_FREQ_COEFFS];
     FIXP_DBL EnergyTotal,newLowbandEnergy,newHighbandEnergy;
     INT border;
     INT sbrSlots = fMultI(GetInvInt(timeStep),no_cols);
+    C_ALLOC_SCRATCH_START(_EnergiesM, FIXP_DBL, NUMBER_TIME_SLOTS_2304*MAX_FREQ_COEFFS)
 
     FDK_ASSERT( sbrSlots * timeStep == no_cols );
 
+    EnergiesM = (FIXP_DBL(*)[MAX_FREQ_COEFFS])_EnergiesM;
+
     /*
       Get Lowband-energy over a range of 2 frames (Look half a frame back and ahead).
     */
@@ -324,16 +401,13 @@ FDKsbrEnc_frameSplitter(FIXP_DBL **Energies,
 
     newHighbandEnergy = addHighbandEnergies(Energies,
                                             scaleEnergies,
+                                            YBufferWriteOffset,
                                             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 */
@@ -343,23 +417,39 @@ FDKsbrEnc_frameSplitter(FIXP_DBL **Energies,
          of a FIXFIX-frame with 2 envelopes. */
       border = (sbrSlots+1) >> 1;
 
+      if ( (INT)EnergyTotal&0xffffffe0 && (scaleEnergies[0]<32 || scaleEnergies[1]<32) ) /* i.e. > 31 */ {
       delta = spectralChange(EnergiesM,
                              scaleEnergies,
                              EnergyTotal,
                              nSfb,
                              0,
                              border,
-                             sbrSlots);
+                             YBufferWriteOffset,
+                             sbrSlots,
+                            &delta_e
+                             );
+      } else {
+        delta = FL2FXCONST_DBL(0.0f);
+        delta_e = 0;
+
+        /* set tonality to 0 when energy is very low, since the amplitude
+           resolution should then be low as well                          */
+        *tonality = FL2FXCONST_DBL(0.0f);
+      }
+
 
-      if (delta > (h_sbrTransientDetector->split_thr >> LD_DATA_SHIFT)) /* delta scaled by 1/64 */
+      if ( fIsLessThan(h_sbrTransientDetector->split_thr_m, h_sbrTransientDetector->split_thr_e, delta, delta_e) ) {
         tran_vector[0] = 1; /* Set flag for splitting */
-      else
+      } else {
         tran_vector[0] = 0;
+      }
+
     }
 
     /* Update prevLowBandEnergy */
     h_sbrTransientDetector->prevLowBandEnergy = newLowbandEnergy;
     h_sbrTransientDetector->prevHighBandEnergy = newHighbandEnergy;
+    C_ALLOC_SCRATCH_END(_EnergiesM, FIXP_DBL, NUMBER_TIME_SLOTS_2304*MAX_FREQ_COEFFS)
   }
 }
 
@@ -636,6 +726,7 @@ FDKsbrEnc_transientDetect(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTran,
 
 int
 FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
+                                   UINT  sbrSyntaxFlags, /* SBR syntax flags derived from AOT. */
                                    INT   frameSize,
                                    INT   sampleFreq,
                                    sbrConfigurationPtr params,
@@ -649,8 +740,8 @@ FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientD
 {
     INT totalBitrate = params->codecSettings.standardBitrate * params->codecSettings.nChannels;
     INT codecBitrate = params->codecSettings.bitRate;
-    FIXP_DBL bitrateFactor_fix, framedur_fix;
-    INT scale_0, scale_1;
+    FIXP_DBL bitrateFactor_m, framedur_fix;
+    INT bitrateFactor_e, tmp_e;
 
     FDKmemclear(h_sbrTransientDetector,sizeof(SBR_TRANSIENT_DETECTOR));
 
@@ -658,11 +749,12 @@ FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientD
     h_sbrTransientDetector->tran_off = tran_off;
 
     if(codecBitrate) {
-      bitrateFactor_fix = fDivNorm((FIXP_DBL)totalBitrate, (FIXP_DBL)(codecBitrate<<2),&scale_0);
+      bitrateFactor_m = fDivNorm((FIXP_DBL)totalBitrate, (FIXP_DBL)(codecBitrate<<2),&bitrateFactor_e);
+      bitrateFactor_e += 2;
     }
     else {
-      bitrateFactor_fix = FL2FXCONST_DBL(1.0/4.0);
-      scale_0 = 0;
+      bitrateFactor_m = FL2FXCONST_DBL(1.0/4.0);
+      bitrateFactor_e = 2;
     }
 
     framedur_fix = fDivNorm(frameSize, sampleFreq);
@@ -674,9 +766,13 @@ FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientD
     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);
+    tmp = fDivNorm(FL2FXCONST_DBL(0.000075), fPow2(tmp), &tmp_e);
 
-    scale_1 = (scale_1 + scale_0 + 2);
+    bitrateFactor_e = (tmp_e + bitrateFactor_e);
+
+  if(sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) {
+    bitrateFactor_e--; /* divide by 2 */
+  }
 
     FDK_ASSERT(no_cols <= QMF_MAX_TIME_SLOTS);
     FDK_ASSERT(no_rows <= QMF_CHANNELS);
@@ -684,7 +780,8 @@ FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientD
     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;
-    h_sbrTransientDetector->split_thr = scaleValueSaturate(fMult(tmp, bitrateFactor_fix), scale_1);     
+    h_sbrTransientDetector->split_thr_m = fMult(tmp, bitrateFactor_m);
+    h_sbrTransientDetector->split_thr_e = bitrateFactor_e;
     h_sbrTransientDetector->no_rows = no_rows;
     h_sbrTransientDetector->mode = params->tran_det_mode;
     h_sbrTransientDetector->prevLowBandEnergy = FL2FXCONST_DBL(0.0f);
@@ -692,3 +789,281 @@ FDKsbrEnc_InitSbrTransientDetector(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientD
     return (0);
 }
 
+
+#define ENERGY_SCALING_SIZE 32
+
+INT FDKsbrEnc_InitSbrFastTransientDetector(
+        HANDLE_FAST_TRAN_DET h_sbrFastTransientDetector,
+        const INT time_slots_per_frame,
+        const INT bandwidth_qmf_slot,
+        const INT no_qmf_channels,
+        const INT sbr_qmf_1st_band
+        )
+{
+
+  int i, e;
+  int buff_size;
+  FIXP_DBL myExp;
+  FIXP_DBL myExpSlot;
+
+  h_sbrFastTransientDetector->lookahead = TRAN_DET_LOOKAHEAD;
+  h_sbrFastTransientDetector->nTimeSlots = time_slots_per_frame;
+
+  buff_size = h_sbrFastTransientDetector->nTimeSlots + h_sbrFastTransientDetector->lookahead;
+
+  for(i=0; i< buff_size; i++) {
+    h_sbrFastTransientDetector->delta_energy[i] = FL2FXCONST_DBL(0.0f);
+    h_sbrFastTransientDetector->energy_timeSlots[i] = FL2FXCONST_DBL(0.0f);
+    h_sbrFastTransientDetector->lowpass_energy[i] = FL2FXCONST_DBL(0.0f);
+    h_sbrFastTransientDetector->transientCandidates[i] = 0;
+  }
+
+  FDK_ASSERT(bandwidth_qmf_slot > 0.f);
+  h_sbrFastTransientDetector->stopBand  = fMin(TRAN_DET_STOP_FREQ/bandwidth_qmf_slot, no_qmf_channels);
+  h_sbrFastTransientDetector->startBand = fMin(sbr_qmf_1st_band, h_sbrFastTransientDetector->stopBand - TRAN_DET_MIN_QMFBANDS);
+
+  FDK_ASSERT(h_sbrFastTransientDetector->startBand < no_qmf_channels);
+  FDK_ASSERT(h_sbrFastTransientDetector->startBand < h_sbrFastTransientDetector->stopBand);
+  FDK_ASSERT(h_sbrFastTransientDetector->startBand > 1);
+  FDK_ASSERT(h_sbrFastTransientDetector->stopBand > 1);
+
+  /* the energy weighting and adding up has a headroom of 6 Bits,
+     so up to 64 bands can be added without potential overflow. */
+  FDK_ASSERT(h_sbrFastTransientDetector->stopBand - h_sbrFastTransientDetector->startBand <= 64);
+
+  /* QMF_HP_dB_SLOPE_FIX says that we want a 20 dB per 16 kHz HP filter.
+     The following lines map this to the QMF bandwidth. */
+  #define EXP_E 7 /* QMF_CHANNELS (=64) multiplications max, max. allowed sum is 0.5 */
+  myExp = fMultNorm(QMF_HP_dBd_SLOPE_FIX, (FIXP_DBL)bandwidth_qmf_slot, &e);
+  myExp = scaleValueSaturate(myExp, e+0+DFRACT_BITS-1-EXP_E);
+  myExpSlot = myExp;
+
+  for(i=0; i<QMF_CHANNELS; i++){
+    /* Calculate dBf over all qmf bands:
+       dBf = (10^(0.002266f/10*bw(slot)))^(band) =
+           = 2^(log2(10)*0.002266f/10*bw(slot)*band) =
+           = 2^(0.00075275f*bw(slot)*band)                                   */
+
+    FIXP_DBL dBf_m;        /* dBf mantissa        */
+    INT dBf_e;             /* dBf exponent        */
+    INT tmp;
+
+    INT dBf_int;           /* dBf integer part    */
+    FIXP_DBL dBf_fract;    /* dBf fractional part */
+
+    /* myExp*(i+1) = myExp_int - myExp_fract
+       myExp*(i+1) is split up here for better accuracy of CalcInvLdData(),
+       for its result can be split up into an integer and a fractional part */
+
+    /* Round up to next integer */
+    FIXP_DBL myExp_int   = (myExpSlot & (FIXP_DBL)0xfe000000) + (FIXP_DBL)0x02000000;
+
+    /* This is the fractional part that needs to be substracted */
+    FIXP_DBL myExp_fract = myExp_int - myExpSlot;
+
+    /* Calc integer part */
+    dBf_int   = CalcInvLdData(myExp_int);
+    /* The result needs to be re-scaled. The ld(myExp_int) had been scaled by EXP_E,
+       the CalcInvLdData expects the operand to be scaled by LD_DATA_SHIFT.
+       Therefore, the correctly scaled result is dBf_int^(2^(EXP_E-LD_DATA_SHIFT)),
+       which is dBf_int^2 */
+    dBf_int  *= dBf_int;
+
+    /* Calc fractional part */
+    dBf_fract = CalcInvLdData(-myExp_fract);
+    /* The result needs to be re-scaled. The ld(myExp_fract) had been scaled by EXP_E,
+       the CalcInvLdData expects the operand to be scaled by LD_DATA_SHIFT.
+       Therefore, the correctly scaled result is dBf_fract^(2^(EXP_E-LD_DATA_SHIFT)),
+       which is dBf_fract^2 */
+    dBf_fract = fMultNorm(dBf_fract, dBf_fract, &tmp);
+
+    /* Get worst case scaling of multiplication result */
+    dBf_e = (DFRACT_BITS-1 - tmp) - CountLeadingBits(dBf_int);
+
+    /* Now multiply integer with fractional part of the result, thus resulting
+       in the overall accurate fractional result */
+    dBf_m = fMultNorm(dBf_int, dBf_fract, &e);
+    dBf_m = scaleValueSaturate(dBf_m, e+DFRACT_BITS-1+tmp-dBf_e);
+    myExpSlot += myExp;
+
+    /* Keep the results */
+    h_sbrFastTransientDetector->dBf_m[i] = dBf_m;
+    h_sbrFastTransientDetector->dBf_e[i] = dBf_e;
+
+  }
+
+  /* Make sure that dBf is greater than 1.0 (because it should be a highpass) */
+  /* ... */
+
+  return 0;
+}
+
+void FDKsbrEnc_fastTransientDetect(
+        const HANDLE_FAST_TRAN_DET          h_sbrFastTransientDetector,
+        const FIXP_DBL              *const *Energies,
+        const int                   *const  scaleEnergies,
+        const INT                           YBufferWriteOffset,
+              UCHAR                 *const  tran_vector
+        )
+{
+  int timeSlot, band;
+
+  FIXP_DBL max_delta_energy;   /* helper to store maximum energy ratio          */
+  int max_delta_energy_scale;  /* helper to store scale of maximum energy ratio */
+  int ind_max             = 0; /* helper to store index of maximum energy ratio */
+  int isTransientInFrame  = 0;
+
+  const int nTimeSlots         = h_sbrFastTransientDetector->nTimeSlots;
+  const int lookahead          = h_sbrFastTransientDetector->lookahead;
+  const int startBand          = h_sbrFastTransientDetector->startBand;
+  const int stopBand           = h_sbrFastTransientDetector->stopBand;
+
+  int * transientCandidates    = h_sbrFastTransientDetector->transientCandidates;
+
+  FIXP_DBL * energy_timeSlots  = h_sbrFastTransientDetector->energy_timeSlots;
+  int * energy_timeSlots_scale = h_sbrFastTransientDetector->energy_timeSlots_scale;
+
+  FIXP_DBL * delta_energy      = h_sbrFastTransientDetector->delta_energy;
+  int * delta_energy_scale     = h_sbrFastTransientDetector->delta_energy_scale;
+
+  const FIXP_DBL thr           = TRAN_DET_THRSHLD;
+  const INT      thr_scale     = TRAN_DET_THRSHLD_SCALE;
+
+  /*reset transient info*/
+  tran_vector[2] = 0;
+
+  /* reset transient candidates */
+  FDKmemclear(transientCandidates+lookahead, nTimeSlots*sizeof(int));
+
+  for(timeSlot = lookahead; timeSlot < nTimeSlots + lookahead; timeSlot++) {
+    int i, norm;
+    FIXP_DBL tmpE           = FL2FXCONST_DBL(0.0f);
+    int headroomEnSlot      = DFRACT_BITS-1;
+
+    FIXP_DBL smallNRG = FL2FXCONST_DBL(1e-2f);
+    FIXP_DBL denominator;
+    INT denominator_scale;
+
+    /* determine minimum headroom of energy values for this timeslot */
+    for(band = startBand; band < stopBand; band++) {
+      int tmp_headroom = fNormz(Energies[timeSlot][band])-1;
+      if(tmp_headroom < headroomEnSlot){
+        headroomEnSlot = tmp_headroom;
+      }
+    }
+
+    for(i = 0, band = startBand; band < stopBand; band++, i++) {
+      /* energy is weighted by weightingfactor stored in dBf_m array */
+      /* dBf_m index runs from 0 to stopBand-startband               */
+      /* energy shifted by calculated headroom for maximum precision */
+      FIXP_DBL weightedEnergy = fMult(Energies[timeSlot][band]<<headroomEnSlot, h_sbrFastTransientDetector->dBf_m[i]);
+
+      /* energy is added up                                                */
+      /* shift by 6 to have a headroom for maximum 64 additions            */
+      /* shift by dBf_e to handle weighting factor dependent scale factors */
+      tmpE += weightedEnergy >> (6 + (10 - h_sbrFastTransientDetector->dBf_e[i]));
+    }
+
+    /* store calculated energy for timeslot */
+    energy_timeSlots[timeSlot] = tmpE;
+
+    /* calculate overall scale factor for energy of this timeslot                                                             */
+    /* =   original scale factor of energies (-scaleEnergies[0]+2*QMF_SCALE_OFFSET or -scaleEnergies[1]+2*QMF_SCALE_OFFSET    */
+    /*     depending on YBufferWriteOffset)                                                                                   */
+    /*   + weighting factor scale            (10)                                                                             */
+    /*   + adding up scale factor            ( 6)                                                                             */
+    /*   - headroom of energy value          (headroomEnSlot)                                                                 */
+    if(timeSlot < YBufferWriteOffset){
+      energy_timeSlots_scale[timeSlot] = (-scaleEnergies[0]+2*QMF_SCALE_OFFSET) + (10+6) - headroomEnSlot;
+    } else {
+      energy_timeSlots_scale[timeSlot] = (-scaleEnergies[1]+2*QMF_SCALE_OFFSET) + (10+6) - headroomEnSlot;
+    }
+
+    /* Add a small energy to the denominator, thus making the transient
+       detection energy-dependent. Loud transients are being detected,
+       silent ones not. */
+
+    /* make sure that smallNRG does not overflow */
+    if ( -energy_timeSlots_scale[timeSlot-1] + 1 > 5 )
+    {
+      denominator = smallNRG;
+      denominator_scale = 0;
+    } else {
+      /* Leave an additional headroom of 1 bit for this addition. */
+      smallNRG = scaleValue(smallNRG, -(energy_timeSlots_scale[timeSlot-1] + 1));
+      denominator = (energy_timeSlots[timeSlot-1]>>1) + smallNRG;
+      denominator_scale = energy_timeSlots_scale[timeSlot-1]+1;
+    }
+
+    delta_energy[timeSlot] = fDivNorm(energy_timeSlots[timeSlot], denominator, &norm);
+    delta_energy_scale[timeSlot] = energy_timeSlots_scale[timeSlot] - denominator_scale + norm;
+  }
+
+  /*get transient candidates*/
+  /* For every timeslot, check if delta(E) exceeds the threshold. If it did,
+     it could potentially be marked as a transient candidate. However, the 2
+     slots before the current one must not be transients with an energy higher
+     than 1.4*E(current). If both aren't transients or if the energy of the
+     current timesolot is more than 1.4 times higher than the energy in the
+     last or the one before the last slot, it is marked as a transient.*/
+
+  FDK_ASSERT(lookahead >= 2);
+  for(timeSlot = lookahead; timeSlot < nTimeSlots + lookahead; timeSlot++) {
+    FIXP_DBL energy_cur_slot_weighted = fMult(energy_timeSlots[timeSlot],FL2FXCONST_DBL(1.0f/1.4f));
+    if( !fIsLessThan(delta_energy[timeSlot], delta_energy_scale[timeSlot], thr, thr_scale) &&
+        ( ((transientCandidates[timeSlot-2]==0) && (transientCandidates[timeSlot-1]==0)) ||
+          !fIsLessThan(energy_cur_slot_weighted, energy_timeSlots_scale[timeSlot], energy_timeSlots[timeSlot-1], energy_timeSlots_scale[timeSlot-1] ) ||
+          !fIsLessThan(energy_cur_slot_weighted, energy_timeSlots_scale[timeSlot], energy_timeSlots[timeSlot-2], energy_timeSlots_scale[timeSlot-2] )
+        )
+      )
+{
+      /* in case of strong transients, subsequent
+       * qmf slots might be recognized as transients. */
+      transientCandidates[timeSlot] = 1;
+    }
+  }
+
+  /*get transient with max energy*/
+  max_delta_energy   = FL2FXCONST_DBL(0.0f);
+  max_delta_energy_scale = 0;
+  ind_max = 0;
+  isTransientInFrame = 0;
+  for(timeSlot = 0; timeSlot < nTimeSlots; timeSlot++) {
+    int scale = fMax(delta_energy_scale[timeSlot], max_delta_energy_scale);
+    if(transientCandidates[timeSlot] && ( (delta_energy[timeSlot] >> (scale - delta_energy_scale[timeSlot])) > (max_delta_energy >> (scale - max_delta_energy_scale)) ) ) {
+      max_delta_energy   = delta_energy[timeSlot];
+      max_delta_energy_scale = scale;
+      ind_max            = timeSlot;
+      isTransientInFrame = 1;
+    }
+  }
+
+  /*from all transient candidates take the one with the biggest energy*/
+  if(isTransientInFrame) {
+    tran_vector[0] = ind_max;
+    tran_vector[1] = 1;
+  } else {
+    /*reset transient info*/
+    tran_vector[0] = tran_vector[1] = 0;
+  }
+
+  /*check for transients in lookahead*/
+  for(timeSlot = nTimeSlots; timeSlot < nTimeSlots + lookahead; timeSlot++) {
+    if(transientCandidates[timeSlot]) {
+      tran_vector[2] = 1;
+    }
+  }
+
+  /*update buffers*/
+  for(timeSlot = 0; timeSlot < lookahead; timeSlot++) {
+    transientCandidates[timeSlot] = transientCandidates[nTimeSlots + timeSlot];
+
+    /* fixpoint stuff */
+    energy_timeSlots[timeSlot]    = energy_timeSlots[nTimeSlots + timeSlot];
+    energy_timeSlots_scale[timeSlot]  = energy_timeSlots_scale[nTimeSlots + timeSlot];
+
+    delta_energy[timeSlot]     = delta_energy[nTimeSlots + timeSlot];
+    delta_energy_scale[timeSlot]   = delta_energy_scale[nTimeSlots + timeSlot];
+  }
+}
+
diff --git a/libSBRenc/src/tran_det.h b/libSBRenc/src/tran_det.h
index 95b5d2e..6fe1023 100644
--- a/libSBRenc/src/tran_det.h
+++ b/libSBRenc/src/tran_det.h
@@ -2,7 +2,7 @@
 /* -----------------------------------------------------------------------------------------------------------
 Software License for The Fraunhofer FDK AAC Codec Library for Android
 
-© Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
+© Copyright  1995 - 2015 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   All rights reserved.
 
  1.    INTRODUCTION
@@ -96,7 +96,8 @@ typedef struct
   FIXP_DBL  transients[QMF_MAX_TIME_SLOTS+(QMF_MAX_TIME_SLOTS/2)];
   FIXP_DBL  thresholds[QMF_CHANNELS];
   FIXP_DBL  tran_thr;              /* Master threshold for transient signals */
-  FIXP_DBL  split_thr;             /* Threshold for splitting FIXFIX-frames into 2 env */
+  FIXP_DBL  split_thr_m;           /* Threshold for splitting FIXFIX-frames into 2 env */
+  INT       split_thr_e;           /* Scale for splitting threshold */
   FIXP_DBL  prevLowBandEnergy;     /* Energy of low band */
   FIXP_DBL  prevHighBandEnergy;    /* Energy of high band */
   INT    tran_fc;                  /* Number of lowband subbands to discard  */
@@ -112,6 +113,57 @@ SBR_TRANSIENT_DETECTOR;
 
 typedef SBR_TRANSIENT_DETECTOR *HANDLE_SBR_TRANSIENT_DETECTOR;
 
+#define TRAN_DET_LOOKAHEAD 2
+#define TRAN_DET_START_FREQ 4500  /*start frequency for transient detection*/
+#define TRAN_DET_STOP_FREQ  13500 /*stop frequency for transient detection*/
+#define TRAN_DET_MIN_QMFBANDS 4 /* minimum qmf bands for transient detection */
+#define QMF_HP_dBd_SLOPE_FIX FL2FXCONST_DBL(0.00075275f) /* 0.002266f/10 * log2(10) */
+#define TRAN_DET_THRSHLD FL2FXCONST_DBL(3.2f/4.f)
+#define TRAN_DET_THRSHLD_SCALE (2)
+
+typedef struct
+{
+  INT transientCandidates[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+  INT nTimeSlots;
+  INT lookahead;
+  INT startBand;
+  INT stopBand;
+
+  FIXP_DBL dBf_m[QMF_CHANNELS];
+  INT      dBf_e[QMF_CHANNELS];
+
+  FIXP_DBL energy_timeSlots[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+  INT      energy_timeSlots_scale[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+
+  FIXP_DBL delta_energy[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+  INT      delta_energy_scale[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+
+  FIXP_DBL lowpass_energy[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+  INT      lowpass_energy_scale[QMF_MAX_TIME_SLOTS + TRAN_DET_LOOKAHEAD];
+#if defined (FTD_LOG)
+  FDKFILE *ftd_log;
+#endif
+}
+FAST_TRAN_DETECTOR;
+typedef FAST_TRAN_DETECTOR *HANDLE_FAST_TRAN_DET;
+
+
+INT FDKsbrEnc_InitSbrFastTransientDetector(
+        HANDLE_FAST_TRAN_DET h_sbrFastTransientDetector,
+        const INT time_slots_per_frame,
+        const INT bandwidth_qmf_slot,
+        const INT no_qmf_channels,
+        const INT sbr_qmf_1st_band
+        );
+
+void FDKsbrEnc_fastTransientDetect(
+        const HANDLE_FAST_TRAN_DET          h_sbrFastTransientDetector,
+        const FIXP_DBL              *const *Energies,
+        const int                   *const  scaleEnergies,
+        const INT                           YBufferWriteOffset,
+              UCHAR                 *const  tran_vector
+        );
+
 void
 FDKsbrEnc_transientDetect(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
                           FIXP_DBL **Energies,
@@ -124,6 +176,7 @@ FDKsbrEnc_transientDetect(HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
 
 int
 FDKsbrEnc_InitSbrTransientDetector (HANDLE_SBR_TRANSIENT_DETECTOR h_sbrTransientDetector,
+                            UINT  sbrSyntaxFlags, /* SBR syntax flags derived from AOT. */
                             INT   frameSize,
                             INT   sampleFreq,
                             sbrConfigurationPtr params,
@@ -145,6 +198,6 @@ FDKsbrEnc_frameSplitter(FIXP_DBL **Energies,
                         int YBufferSzShift,
                         int nSfb,
                         int timeStep,
-                        int no_cols);
-
+                        int no_cols,
+                        FIXP_DBL* tonality);
 #endif