path: root/libSBRenc/src/invf_est.cpp

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

                     (C) Copyright Fraunhofer IIS (2004)
                               All Rights Reserved

    Please be advised that this software and/or program delivery is
    Confidential Information of Fraunhofer and subject to and covered by the

    Fraunhofer IIS Software Evaluation Agreement
    between Google Inc. and  Fraunhofer
    effective and in full force since March 1, 2012.

    You may use this software and/or program only under the terms and
    conditions described in the above mentioned Fraunhofer IIS Software
    Evaluation Agreement. Any other and/or further use requires a separate agreement.


   This software and/or program is protected by copyright law and international
   treaties. Any reproduction or distribution of this software and/or program,
   or any portion of it, may result in severe civil and criminal penalties, and
   will be prosecuted to the maximum extent possible under law.

 $Id$

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

#include "invf_est.h"
#include "sbr_misc.h"

#include "genericStds.h"

#define MAX_NUM_REGIONS 10
#define SCALE_FAC_QUO   512.0f
#define SCALE_FAC_NRG   256.0f

#ifndef min
#define min(a,b) ( a < b ? a:b)
#endif

#ifndef max
#define max(a,b) ( a > b ? a:b)
#endif

static const FIXP_DBL quantStepsSbr[4]  =  { 0x00400000, 0x02800000, 0x03800000, 0x04c00000 } ;    /* table scaled with SCALE_FAC_QUO */
static const FIXP_DBL quantStepsOrig[4] =  { 0x00000000, 0x00c00000, 0x01c00000, 0x02800000 } ;    /* table scaled with SCALE_FAC_QUO */
static const FIXP_DBL nrgBorders[4]     =  { 0x0c800000, 0x0f000000, 0x11800000, 0x14000000 } ;    /* table scaled with SCALE_FAC_NRG */

static const DETECTOR_PARAMETERS detectorParamsAAC = {
    quantStepsSbr,
    quantStepsOrig,
    nrgBorders,
    4,                              /* Number of borders SBR. */
    4,                              /* Number of borders orig. */
    4,                              /* Number of borders Nrg. */
    {                               /* Region space. */
      {INVF_MID_LEVEL,   INVF_LOW_LEVEL,  INVF_OFF,        INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_MID_LEVEL,   INVF_LOW_LEVEL,  INVF_OFF,        INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
    },/*------------------------ regionOrig ---------------------------------*/
    {                               /* Region space transient. */
      {INVF_LOW_LEVEL,   INVF_LOW_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_LOW_LEVEL,   INVF_LOW_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
    },/*------------------------ regionOrig ---------------------------------*/
    {-4, -3, -2, -1, 0} /* Reduction factor of the inverse filtering for low energies.*/
};

static const FIXP_DBL hysteresis = 0x00400000 ; /* Delta value for hysteresis. scaled with SCALE_FAC_QUO */

/*
 * AAC+SBR PARAMETERS for Speech
 *********************************/
static const DETECTOR_PARAMETERS detectorParamsAACSpeech = {
    quantStepsSbr,
    quantStepsOrig,
    nrgBorders,
    4,                              /* Number of borders SBR. */
    4,                              /* Number of borders orig. */
    4,                              /* Number of borders Nrg. */
    {                               /* Region space. */
      {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
    },/*------------------------ regionOrig ---------------------------------*/
    {                               /* Region space transient. */
      {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
      {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
    },/*------------------------ regionOrig ---------------------------------*/
    {-4, -3, -2, -1, 0} /* Reduction factor of the inverse filtering for low energies.*/
};

/*
 * Smoothing filters.
 ************************/
typedef const FIXP_DBL FIR_FILTER[5];

static const FIR_FILTER fir_0 = { 0x7fffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000 } ;
static const FIR_FILTER fir_1 = { 0x2aaaaa80, 0x555554ff, 0x00000000, 0x00000000, 0x00000000 } ;
static const FIR_FILTER fir_2 = { 0x10000000, 0x30000000, 0x40000000, 0x00000000, 0x00000000 } ;
static const FIR_FILTER fir_3 = { 0x077f80e8, 0x199999a0, 0x2bb3b240, 0x33333340, 0x00000000 } ;
static const FIR_FILTER fir_4 = { 0x04130598, 0x0ebdb000, 0x1becfa60, 0x2697a4c0, 0x2aaaaa80 } ;


static const FIR_FILTER *const fir_table[5] = {
  &fir_0,
  &fir_1,
  &fir_2,
  &fir_3,
  &fir_4
};

/**************************************************************************/
/*!
  \brief     Calculates the values used for the detector.


  \return    none

*/
/**************************************************************************/
static void
calculateDetectorValues(FIXP_DBL **quotaMatrixOrig,       /*!< Matrix holding the tonality values of the original. */
                        SCHAR    *indexVector,            /*!< Index vector to obtain the patched data. */
                        FIXP_DBL *nrgVector,              /*!< Energy vector. */
                        DETECTOR_VALUES *detectorValues,  /*!< pointer to DETECTOR_VALUES struct. */
                        INT startChannel,                 /*!< Start channel. */
                        INT stopChannel,                  /*!< Stop channel. */
                        INT startIndex,                   /*!< Start index. */
                        INT stopIndex,                    /*!< Stop index. */
                        INT numberOfStrongest             /*!< The number of sorted tonal components to be considered. */
                        )
{
  INT i,temp, j;

  const FIXP_DBL* filter = *fir_table[INVF_SMOOTHING_LENGTH];
  FIXP_DBL origQuotaMeanStrongest, sbrQuotaMeanStrongest;
  FIXP_DBL origQuota, sbrQuota;
  FIXP_DBL invIndex, invChannel, invTemp;
  FIXP_DBL quotaVecOrig[64], quotaVecSbr[64];

  FDKmemclear(quotaVecOrig,64*sizeof(FIXP_DBL));
  FDKmemclear(quotaVecSbr,64*sizeof(FIXP_DBL));

  invIndex = GetInvInt(stopIndex-startIndex);
  invChannel = GetInvInt(stopChannel-startChannel);

  /*
   Calculate the mean value, over the current time segment, for the original, the HFR
   and the difference, over all channels in the current frequency range.
   NOTE: the averaging is done on the values quota/(1 - quota + RELAXATION).
   */

  /* The original, the sbr signal and the total energy */
  detectorValues->avgNrg = FL2FXCONST_DBL(0.0f);
  for(j=startIndex; j<stopIndex; j++) {
    for(i=startChannel; i<stopChannel; i++) {
      quotaVecOrig[i] += fMult(quotaMatrixOrig[j][i], invIndex);

      if(indexVector[i] != -1)
        quotaVecSbr[i] += fMult(quotaMatrixOrig[j][indexVector[i]], invIndex);
    }
    detectorValues->avgNrg += fMult(nrgVector[j], invIndex);
  }

  /*
   Calculate the mean value, over the current frequency range, for the original, the HFR
   and the difference. Also calculate the same mean values for the three vectors, but only
   includeing the x strongest copmponents.
   */

  origQuota = FL2FXCONST_DBL(0.0f);
  sbrQuota  = FL2FXCONST_DBL(0.0f);
  for(i=startChannel; i<stopChannel; i++) {
    origQuota += fMultDiv2(quotaVecOrig[i], invChannel);
    sbrQuota  += fMultDiv2(quotaVecSbr[i], invChannel);
  }

  /*
   Calculate the mean value for the x strongest components
  */
  FDKsbrEnc_Shellsort_fract(quotaVecOrig+startChannel,stopChannel-startChannel);
  FDKsbrEnc_Shellsort_fract(quotaVecSbr+startChannel,stopChannel-startChannel);

  origQuotaMeanStrongest = FL2FXCONST_DBL(0.0f);
  sbrQuotaMeanStrongest  = FL2FXCONST_DBL(0.0f);

  temp = min(stopChannel - startChannel, numberOfStrongest);
  invTemp = GetInvInt(temp);

  for(i=0; i<temp; i++) {
    origQuotaMeanStrongest += fMultDiv2(quotaVecOrig[i + stopChannel - temp], invTemp);
    sbrQuotaMeanStrongest  += fMultDiv2(quotaVecSbr[i + stopChannel - temp], invTemp);
  }

  /*
   The value for the strongest component
  */
  detectorValues->origQuotaMax = quotaVecOrig[stopChannel - 1];
  detectorValues->sbrQuotaMax  = quotaVecSbr[stopChannel - 1];

  /*
   Buffer values
  */
  FDKmemmove(detectorValues->origQuotaMean, detectorValues->origQuotaMean + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
  FDKmemmove(detectorValues->sbrQuotaMean, detectorValues->sbrQuotaMean + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
  FDKmemmove(detectorValues->origQuotaMeanStrongest, detectorValues->origQuotaMeanStrongest + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
  FDKmemmove(detectorValues->sbrQuotaMeanStrongest, detectorValues->sbrQuotaMeanStrongest + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));

  detectorValues->origQuotaMean[INVF_SMOOTHING_LENGTH]          = origQuota<<1;
  detectorValues->sbrQuotaMean[INVF_SMOOTHING_LENGTH]           = sbrQuota<<1;
  detectorValues->origQuotaMeanStrongest[INVF_SMOOTHING_LENGTH] = origQuotaMeanStrongest<<1;
  detectorValues->sbrQuotaMeanStrongest[INVF_SMOOTHING_LENGTH]  = sbrQuotaMeanStrongest<<1;

  /*
   Filter values
  */
  detectorValues->origQuotaMeanFilt = FL2FXCONST_DBL(0.0f);
  detectorValues->sbrQuotaMeanFilt = FL2FXCONST_DBL(0.0f);
  detectorValues->origQuotaMeanStrongestFilt = FL2FXCONST_DBL(0.0f);
  detectorValues->sbrQuotaMeanStrongestFilt = FL2FXCONST_DBL(0.0f);

  for(i=0;i<INVF_SMOOTHING_LENGTH+1;i++) {
    detectorValues->origQuotaMeanFilt += fMult(detectorValues->origQuotaMean[i], filter[i]);
    detectorValues->sbrQuotaMeanFilt  += fMult(detectorValues->sbrQuotaMean[i], filter[i]);
    detectorValues->origQuotaMeanStrongestFilt += fMult(detectorValues->origQuotaMeanStrongest[i], filter[i]);
    detectorValues->sbrQuotaMeanStrongestFilt  += fMult(detectorValues->sbrQuotaMeanStrongest[i], filter[i]);
  }
}

/**************************************************************************/
/*!
  \brief     Returns the region in which the input value belongs.



  \return    region.

*/
/**************************************************************************/
static INT
findRegion(FIXP_DBL currVal,        /*!< The current value. */
           const FIXP_DBL *borders, /*!< The border of the regions. */
           const INT numBorders     /*!< The number of borders. */
           )
{
  INT i;

  if(currVal < borders[0]){
    return 0;
  }

  for(i = 1; i < numBorders; i++){
    if( currVal >= borders[i-1] && currVal < borders[i]){
      return i;
    }
  }

  if(currVal >= borders[numBorders-1]){
    return numBorders;
  }

  return 0;  /* We never get here, it's just to avoid compiler warnings.*/
}

/**************************************************************************/
/*!
  \brief     Makes a clever decision based on the quota vector.


  \return     decision on which invf mode to use

*/
/**************************************************************************/
static INVF_MODE
decisionAlgorithm(const DETECTOR_PARAMETERS *detectorParams,     /*!< Struct with the detector parameters. */
                  DETECTOR_VALUES *detectorValues,               /*!< Struct with the detector values. */
                  INT transientFlag,                             /*!< Flag indicating if there is a transient present.*/
                  INT* prevRegionSbr,                            /*!< The previous region in which the Sbr value was. */
                  INT* prevRegionOrig                            /*!< The previous region in which the Orig value was. */
                  )
{
  INT invFiltLevel, regionSbr, regionOrig, regionNrg;

  /*
   Current thresholds.
   */
  const FIXP_DBL *quantStepsSbr  = detectorParams->quantStepsSbr;
  const FIXP_DBL *quantStepsOrig = detectorParams->quantStepsOrig;
  const FIXP_DBL *nrgBorders     = detectorParams->nrgBorders;
  const INT numRegionsSbr     = detectorParams->numRegionsSbr;
  const INT numRegionsOrig    = detectorParams->numRegionsOrig;
  const INT numRegionsNrg     = detectorParams->numRegionsNrg;

  FIXP_DBL quantStepsSbrTmp[MAX_NUM_REGIONS];
  FIXP_DBL quantStepsOrigTmp[MAX_NUM_REGIONS];

  /*
   Current detector values.
   */
  FIXP_DBL origQuotaMeanFilt;
  FIXP_DBL sbrQuotaMeanFilt;
  FIXP_DBL nrg;

  /* 0.375 = 3.0 / 8.0; 0.31143075889 = log2(RELAXATION)/64.0; 0.625 = log(16)/64.0; 0.6875 = 44/64.0 */
  origQuotaMeanFilt = (fMultDiv2(FL2FXCONST_DBL(2.f*0.375f), (FIXP_DBL)(CalcLdData(max(detectorValues->origQuotaMeanFilt,(FIXP_DBL)1)) + FL2FXCONST_DBL(0.31143075889f)))) << 0;  /* scaled by 1/2^9 */
  sbrQuotaMeanFilt  = (fMultDiv2(FL2FXCONST_DBL(2.f*0.375f), (FIXP_DBL)(CalcLdData(max(detectorValues->sbrQuotaMeanFilt,(FIXP_DBL)1)) + FL2FXCONST_DBL(0.31143075889f)))) << 0;   /* scaled by 1/2^9 */
  /* If energy is zero then we will get different results for different word lengths. */
  nrg               = (fMultDiv2(FL2FXCONST_DBL(2.f*0.375f), (FIXP_DBL)(CalcLdData(detectorValues->avgNrg+(FIXP_DBL)1) + FL2FXCONST_DBL(0.0625f) + FL2FXCONST_DBL(0.6875f)))) << 0;     /* scaled by 1/2^8; 2^44 -> qmf energy scale */

  FDKmemcpy(quantStepsSbrTmp,quantStepsSbr,numRegionsSbr*sizeof(FIXP_DBL));
  FDKmemcpy(quantStepsOrigTmp,quantStepsOrig,numRegionsOrig*sizeof(FIXP_DBL));

  if(*prevRegionSbr < numRegionsSbr)
    quantStepsSbrTmp[*prevRegionSbr] = quantStepsSbr[*prevRegionSbr] + hysteresis;
  if(*prevRegionSbr > 0)
    quantStepsSbrTmp[*prevRegionSbr - 1] = quantStepsSbr[*prevRegionSbr - 1] - hysteresis;

  if(*prevRegionOrig < numRegionsOrig)
    quantStepsOrigTmp[*prevRegionOrig] = quantStepsOrig[*prevRegionOrig] + hysteresis;
  if(*prevRegionOrig > 0)
    quantStepsOrigTmp[*prevRegionOrig - 1] = quantStepsOrig[*prevRegionOrig - 1] - hysteresis;

  regionSbr  = findRegion(sbrQuotaMeanFilt, quantStepsSbrTmp, numRegionsSbr);
  regionOrig = findRegion(origQuotaMeanFilt, quantStepsOrigTmp, numRegionsOrig);
  regionNrg  = findRegion(nrg,nrgBorders,numRegionsNrg);

  *prevRegionSbr = regionSbr;
  *prevRegionOrig = regionOrig;

  /* Use different settings if a transient is present*/
  invFiltLevel = (transientFlag == 1) ? detectorParams->regionSpaceTransient[regionSbr][regionOrig]
                                      : detectorParams->regionSpace[regionSbr][regionOrig];

  /* Compensate for low energy.*/
  invFiltLevel = max(invFiltLevel + detectorParams->EnergyCompFactor[regionNrg],0);

  return (INVF_MODE) (invFiltLevel);
}

/**************************************************************************/
/*!
  \brief     Estiamtion of the inverse filtering level required
             in the decoder.

   A second order LPC is calculated for every filterbank channel, using
   the covariance method. THe ratio between the energy of the predicted
   signal and the energy of the non-predictable signal is calcualted.

  \return    none.

*/
/**************************************************************************/
void
FDKsbrEnc_qmfInverseFilteringDetector(HANDLE_SBR_INV_FILT_EST hInvFilt,  /*!< Handle to the SBR_INV_FILT_EST struct. */
                            FIXP_DBL **quotaMatrix,            /*!< The matrix holding the tonality values of the original. */
                            FIXP_DBL *nrgVector,               /*!< The energy vector. */
                            SCHAR    *indexVector,             /*!< Index vector to obtain the patched data. */
                            INT startIndex,                    /*!< Start index. */
                            INT stopIndex,                     /*!< Stop index. */
                            INT transientFlag,                 /*!< Flag indicating if a transient is present or not.*/
                            INVF_MODE* infVec                  /*!< Vector holding the inverse filtering levels. */
                            )
{
  INT band;

  /*
   * Do the inverse filtering level estimation.
   *****************************************************/
  for(band = 0 ; band < hInvFilt->noDetectorBands; band++){
    INT startChannel = hInvFilt->freqBandTableInvFilt[band];
    INT stopChannel  = hInvFilt->freqBandTableInvFilt[band+1];


    calculateDetectorValues( quotaMatrix,
                             indexVector,
                             nrgVector,
                            &hInvFilt->detectorValues[band],
                             startChannel,
                             stopChannel,
                             startIndex,
                             stopIndex,
                             hInvFilt->numberOfStrongest);

    infVec[band]= decisionAlgorithm( hInvFilt->detectorParams,
                                    &hInvFilt->detectorValues[band],
                                     transientFlag,
                                    &hInvFilt->prevRegionSbr[band],
                                    &hInvFilt->prevRegionOrig[band]);
  }

}


/**************************************************************************/
/*!
  \brief     Initialize an instance of the inverse filtering level estimator.


  \return   errorCode, noError if successful.

*/
/**************************************************************************/
INT
FDKsbrEnc_initInvFiltDetector (HANDLE_SBR_INV_FILT_EST hInvFilt,   /*!< Pointer to a handle to the SBR_INV_FILT_EST struct. */
                       INT* freqBandTableDetector,          /*!< Frequency band table for the inverse filtering. */
                       INT numDetectorBands,                /*!< Number of inverse filtering bands. */
                       UINT useSpeechConfig         /*!< Flag: adapt tuning parameters according to speech*/
                       )
{
  INT i;

  FDKmemclear( hInvFilt,sizeof(SBR_INV_FILT_EST));

  hInvFilt->detectorParams = (useSpeechConfig) ? &detectorParamsAACSpeech
                                               : &detectorParamsAAC ;

  hInvFilt->noDetectorBandsMax = numDetectorBands;

  /*
     Memory initialisation
  */
  for(i=0;i<hInvFilt->noDetectorBandsMax;i++){
    FDKmemclear(&hInvFilt->detectorValues[i], sizeof(DETECTOR_VALUES));
    hInvFilt->prevInvfMode[i]   = INVF_OFF;
    hInvFilt->prevRegionOrig[i] = 0;
    hInvFilt->prevRegionSbr[i]  = 0;
  }

  /*
  Reset the inverse fltering detector.
  */
  FDKsbrEnc_resetInvFiltDetector(hInvFilt,
                       freqBandTableDetector,
                       hInvFilt->noDetectorBandsMax);

  return (0);
}


/**************************************************************************/
/*!
  \brief     resets sbr inverse filtering structure.



  \return   errorCode, noError if successful.

*/
/**************************************************************************/
INT
FDKsbrEnc_resetInvFiltDetector(HANDLE_SBR_INV_FILT_EST hInvFilt, /*!< Handle to the SBR_INV_FILT_EST struct. */
                     INT* freqBandTableDetector,       /*!< Frequency band table for the inverse filtering. */
                     INT numDetectorBands)             /*!< Number of inverse filtering bands. */
{

  hInvFilt->numberOfStrongest     = 1;
  FDKmemcpy(hInvFilt->freqBandTableInvFilt,freqBandTableDetector,(numDetectorBands+1)*sizeof(INT));
  hInvFilt->noDetectorBands = numDetectorBands;

  return (0);
}