libSBRenc/src/invf_est.cpp

   1
   2 /* -----------------------------------------------------------------------------------------------------------
   3 Software License for The Fraunhofer FDK AAC Codec Library for Android
   4
   5 © Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
   6   All rights reserved.
   7
   8  1.    INTRODUCTION
   9 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
  10 the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
  11 This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
  12
  13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
  14 audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
  15 independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
  16 of the MPEG specifications.
  17
  18 Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
  19 may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
  20 individually for the purpose of encoding or decoding bit streams in products that are compliant with
  21 the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
  22 these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
  23 software may already be covered under those patent licenses when it is used for those licensed purposes only.
  24
  25 Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
  26 are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
  27 applications information and documentation.
  28
  29 2.    COPYRIGHT LICENSE
  30
  31 Redistribution and use in source and binary forms, with or without modification, are permitted without
  32 payment of copyright license fees provided that you satisfy the following conditions:
  33
  34 You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
  35 your modifications thereto in source code form.
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  38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
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  40 modifications thereto to recipients of copies in binary form.
  41
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  44
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  46 software or your modifications thereto.
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  49 and the date of any change. For modified versions of the FDK AAC Codec, the term
  50 "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
  51 "Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
  52
  53 3.    NO PATENT LICENSE
  54
  55 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
  56 ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
  57 respect to this software.
  58
  59 You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
  60 by appropriate patent licenses.
  61
  62 4.    DISCLAIMER
  63
  64 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
  65 "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
  66 of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  67 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
  68 including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
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  70 liability, or tort (including negligence), arising in any way out of the use of this software, even if
  71 advised of the possibility of such damage.
  72
  73 5.    CONTACT INFORMATION
  74
  75 Fraunhofer Institute for Integrated Circuits IIS
  76 Attention: Audio and Multimedia Departments - FDK AAC LL
  77 Am Wolfsmantel 33
  78 91058 Erlangen, Germany
  79
  80 www.iis.fraunhofer.de/amm
  81 amm-info@iis.fraunhofer.de
  82 ----------------------------------------------------------------------------------------------------------- */
  83
  84 #include "invf_est.h"
  85 #include "sbr_misc.h"
  86
  87 #include "genericStds.h"
  88
  89 #define MAX_NUM_REGIONS 10
  90 #define SCALE_FAC_QUO   512.0f
  91 #define SCALE_FAC_NRG   256.0f
  92
  93 #ifndef min
  94 #define min(a,b) ( a < b ? a:b)
  95 #endif
  96
  97 #ifndef max
  98 #define max(a,b) ( a > b ? a:b)
  99 #endif
 100
 101 static const FIXP_DBL quantStepsSbr[4]  =  { 0x00400000, 0x02800000, 0x03800000, 0x04c00000 } ;    /* table scaled with SCALE_FAC_QUO */
 102 static const FIXP_DBL quantStepsOrig[4] =  { 0x00000000, 0x00c00000, 0x01c00000, 0x02800000 } ;    /* table scaled with SCALE_FAC_QUO */
 103 static const FIXP_DBL nrgBorders[4]     =  { 0x0c800000, 0x0f000000, 0x11800000, 0x14000000 } ;    /* table scaled with SCALE_FAC_NRG */
 104
 105 static const DETECTOR_PARAMETERS detectorParamsAAC = {
 106     quantStepsSbr,
 107     quantStepsOrig,
 108     nrgBorders,
 109     4,                              /* Number of borders SBR. */
 110     4,                              /* Number of borders orig. */
 111     4,                              /* Number of borders Nrg. */
 112     {                               /* Region space. */
 113       {INVF_MID_LEVEL,   INVF_LOW_LEVEL,  INVF_OFF,        INVF_OFF, INVF_OFF}, /*    |      */
 114       {INVF_MID_LEVEL,   INVF_LOW_LEVEL,  INVF_OFF,        INVF_OFF, INVF_OFF}, /*    |      */
 115       {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
 116       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 117       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
 118     },/*------------------------ regionOrig ---------------------------------*/
 119     {                               /* Region space transient. */
 120       {INVF_LOW_LEVEL,   INVF_LOW_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 121       {INVF_LOW_LEVEL,   INVF_LOW_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 122       {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
 123       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 124       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
 125     },/*------------------------ regionOrig ---------------------------------*/
 126     {-4, -3, -2, -1, 0} /* Reduction factor of the inverse filtering for low energies.*/
 127 };
 128
 129 static const FIXP_DBL hysteresis = 0x00400000 ; /* Delta value for hysteresis. scaled with SCALE_FAC_QUO */
 130
 131 /*
 132  * AAC+SBR PARAMETERS for Speech
 133  *********************************/
 134 static const DETECTOR_PARAMETERS detectorParamsAACSpeech = {
 135     quantStepsSbr,
 136     quantStepsOrig,
 137     nrgBorders,
 138     4,                              /* Number of borders SBR. */
 139     4,                              /* Number of borders orig. */
 140     4,                              /* Number of borders Nrg. */
 141     {                               /* Region space. */
 142       {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 143       {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 144       {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
 145       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 146       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
 147     },/*------------------------ regionOrig ---------------------------------*/
 148     {                               /* Region space transient. */
 149       {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 150       {INVF_MID_LEVEL,   INVF_MID_LEVEL,  INVF_LOW_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 151       {INVF_HIGH_LEVEL,  INVF_MID_LEVEL,  INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /* regionSbr */
 152       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}, /*    |      */
 153       {INVF_HIGH_LEVEL,  INVF_HIGH_LEVEL, INVF_MID_LEVEL,  INVF_OFF, INVF_OFF}  /*    |      */
 154     },/*------------------------ regionOrig ---------------------------------*/
 155     {-4, -3, -2, -1, 0} /* Reduction factor of the inverse filtering for low energies.*/
 156 };
 157
 158 /*
 159  * Smoothing filters.
 160  ************************/
 161 typedef const FIXP_DBL FIR_FILTER[5];
 162
 163 static const FIR_FILTER fir_0 = { 0x7fffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000 } ;
 164 static const FIR_FILTER fir_1 = { 0x2aaaaa80, 0x555554ff, 0x00000000, 0x00000000, 0x00000000 } ;
 165 static const FIR_FILTER fir_2 = { 0x10000000, 0x30000000, 0x40000000, 0x00000000, 0x00000000 } ;
 166 static const FIR_FILTER fir_3 = { 0x077f80e8, 0x199999a0, 0x2bb3b240, 0x33333340, 0x00000000 } ;
 167 static const FIR_FILTER fir_4 = { 0x04130598, 0x0ebdb000, 0x1becfa60, 0x2697a4c0, 0x2aaaaa80 } ;
 168
 169
 170 static const FIR_FILTER *const fir_table[5] = {
 171   &fir_0,
 172   &fir_1,
 173   &fir_2,
 174   &fir_3,
 175   &fir_4
 176 };
 177
 178 /**************************************************************************/
 179 /*!
 180   \brief     Calculates the values used for the detector.
 181
 182
 183   \return    none
 184
 185 */
 186 /**************************************************************************/
 187 static void
 188 calculateDetectorValues(FIXP_DBL **quotaMatrixOrig,       /*!< Matrix holding the tonality values of the original. */
 189                         SCHAR    *indexVector,            /*!< Index vector to obtain the patched data. */
 190                         FIXP_DBL *nrgVector,              /*!< Energy vector. */
 191                         DETECTOR_VALUES *detectorValues,  /*!< pointer to DETECTOR_VALUES struct. */
 192                         INT startChannel,                 /*!< Start channel. */
 193                         INT stopChannel,                  /*!< Stop channel. */
 194                         INT startIndex,                   /*!< Start index. */
 195                         INT stopIndex,                    /*!< Stop index. */
 196                         INT numberOfStrongest             /*!< The number of sorted tonal components to be considered. */
 197                         )
 198 {
 199   INT i,temp, j;
 200
 201   const FIXP_DBL* filter = *fir_table[INVF_SMOOTHING_LENGTH];
 202   FIXP_DBL origQuotaMeanStrongest, sbrQuotaMeanStrongest;
 203   FIXP_DBL origQuota, sbrQuota;
 204   FIXP_DBL invIndex, invChannel, invTemp;
 205   FIXP_DBL quotaVecOrig[64], quotaVecSbr[64];
 206
 207   FDKmemclear(quotaVecOrig,64*sizeof(FIXP_DBL));
 208   FDKmemclear(quotaVecSbr,64*sizeof(FIXP_DBL));
 209
 210   invIndex = GetInvInt(stopIndex-startIndex);
 211   invChannel = GetInvInt(stopChannel-startChannel);
 212
 213   /*
 214    Calculate the mean value, over the current time segment, for the original, the HFR
 215    and the difference, over all channels in the current frequency range.
 216    NOTE: the averaging is done on the values quota/(1 - quota + RELAXATION).
 217    */
 218
 219   /* The original, the sbr signal and the total energy */
 220   detectorValues->avgNrg = FL2FXCONST_DBL(0.0f);
 221   for(j=startIndex; j<stopIndex; j++) {
 222     for(i=startChannel; i<stopChannel; i++) {
 223       quotaVecOrig[i] += fMult(quotaMatrixOrig[j][i], invIndex);
 224
 225       if(indexVector[i] != -1)
 226         quotaVecSbr[i] += fMult(quotaMatrixOrig[j][indexVector[i]], invIndex);
 227     }
 228     detectorValues->avgNrg += fMult(nrgVector[j], invIndex);
 229   }
 230
 231   /*
 232    Calculate the mean value, over the current frequency range, for the original, the HFR
 233    and the difference. Also calculate the same mean values for the three vectors, but only
 234    includeing the x strongest copmponents.
 235    */
 236
 237   origQuota = FL2FXCONST_DBL(0.0f);
 238   sbrQuota  = FL2FXCONST_DBL(0.0f);
 239   for(i=startChannel; i<stopChannel; i++) {
 240     origQuota += fMultDiv2(quotaVecOrig[i], invChannel);
 241     sbrQuota  += fMultDiv2(quotaVecSbr[i], invChannel);
 242   }
 243
 244   /*
 245    Calculate the mean value for the x strongest components
 246   */
 247   FDKsbrEnc_Shellsort_fract(quotaVecOrig+startChannel,stopChannel-startChannel);
 248   FDKsbrEnc_Shellsort_fract(quotaVecSbr+startChannel,stopChannel-startChannel);
 249
 250   origQuotaMeanStrongest = FL2FXCONST_DBL(0.0f);
 251   sbrQuotaMeanStrongest  = FL2FXCONST_DBL(0.0f);
 252
 253   temp = min(stopChannel - startChannel, numberOfStrongest);
 254   invTemp = GetInvInt(temp);
 255
 256   for(i=0; i<temp; i++) {
 257     origQuotaMeanStrongest += fMultDiv2(quotaVecOrig[i + stopChannel - temp], invTemp);
 258     sbrQuotaMeanStrongest  += fMultDiv2(quotaVecSbr[i + stopChannel - temp], invTemp);
 259   }
 260
 261   /*
 262    The value for the strongest component
 263   */
 264   detectorValues->origQuotaMax = quotaVecOrig[stopChannel - 1];
 265   detectorValues->sbrQuotaMax  = quotaVecSbr[stopChannel - 1];
 266
 267   /*
 268    Buffer values
 269   */
 270   FDKmemmove(detectorValues->origQuotaMean, detectorValues->origQuotaMean + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
 271   FDKmemmove(detectorValues->sbrQuotaMean, detectorValues->sbrQuotaMean + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
 272   FDKmemmove(detectorValues->origQuotaMeanStrongest, detectorValues->origQuotaMeanStrongest + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
 273   FDKmemmove(detectorValues->sbrQuotaMeanStrongest, detectorValues->sbrQuotaMeanStrongest + 1, INVF_SMOOTHING_LENGTH*sizeof(FIXP_DBL));
 274
 275   detectorValues->origQuotaMean[INVF_SMOOTHING_LENGTH]          = origQuota<<1;
 276   detectorValues->sbrQuotaMean[INVF_SMOOTHING_LENGTH]           = sbrQuota<<1;
 277   detectorValues->origQuotaMeanStrongest[INVF_SMOOTHING_LENGTH] = origQuotaMeanStrongest<<1;
 278   detectorValues->sbrQuotaMeanStrongest[INVF_SMOOTHING_LENGTH]  = sbrQuotaMeanStrongest<<1;
 279
 280   /*
 281    Filter values
 282   */
 283   detectorValues->origQuotaMeanFilt = FL2FXCONST_DBL(0.0f);
 284   detectorValues->sbrQuotaMeanFilt = FL2FXCONST_DBL(0.0f);
 285   detectorValues->origQuotaMeanStrongestFilt = FL2FXCONST_DBL(0.0f);
 286   detectorValues->sbrQuotaMeanStrongestFilt = FL2FXCONST_DBL(0.0f);
 287
 288   for(i=0;i<INVF_SMOOTHING_LENGTH+1;i++) {
 289     detectorValues->origQuotaMeanFilt += fMult(detectorValues->origQuotaMean[i], filter[i]);
 290     detectorValues->sbrQuotaMeanFilt  += fMult(detectorValues->sbrQuotaMean[i], filter[i]);
 291     detectorValues->origQuotaMeanStrongestFilt += fMult(detectorValues->origQuotaMeanStrongest[i], filter[i]);
 292     detectorValues->sbrQuotaMeanStrongestFilt  += fMult(detectorValues->sbrQuotaMeanStrongest[i], filter[i]);
 293   }
 294 }
 295
 296 /**************************************************************************/
 297 /*!
 298   \brief     Returns the region in which the input value belongs.
 299
 300
 301
 302   \return    region.
 303
 304 */
 305 /**************************************************************************/
 306 static INT
 307 findRegion(FIXP_DBL currVal,        /*!< The current value. */
 308            const FIXP_DBL *borders, /*!< The border of the regions. */
 309            const INT numBorders     /*!< The number of borders. */
 310            )
 311 {
 312   INT i;
 313
 314   if(currVal < borders[0]){
 315     return 0;
 316   }
 317
 318   for(i = 1; i < numBorders; i++){
 319     if( currVal >= borders[i-1] && currVal < borders[i]){
 320       return i;
 321     }
 322   }
 323
 324   if(currVal >= borders[numBorders-1]){
 325     return numBorders;
 326   }
 327
 328   return 0;  /* We never get here, it's just to avoid compiler warnings.*/
 329 }
 330
 331 /**************************************************************************/
 332 /*!
 333   \brief     Makes a clever decision based on the quota vector.
 334
 335
 336   \return     decision on which invf mode to use
 337
 338 */
 339 /**************************************************************************/
 340 static INVF_MODE
 341 decisionAlgorithm(const DETECTOR_PARAMETERS *detectorParams,     /*!< Struct with the detector parameters. */
 342                   DETECTOR_VALUES *detectorValues,               /*!< Struct with the detector values. */
 343                   INT transientFlag,                             /*!< Flag indicating if there is a transient present.*/
 344                   INT* prevRegionSbr,                            /*!< The previous region in which the Sbr value was. */
 345                   INT* prevRegionOrig                            /*!< The previous region in which the Orig value was. */
 346                   )
 347 {
 348   INT invFiltLevel, regionSbr, regionOrig, regionNrg;
 349
 350   /*
 351    Current thresholds.
 352    */
 353   const FIXP_DBL *quantStepsSbr  = detectorParams->quantStepsSbr;
 354   const FIXP_DBL *quantStepsOrig = detectorParams->quantStepsOrig;
 355   const FIXP_DBL *nrgBorders     = detectorParams->nrgBorders;
 356   const INT numRegionsSbr     = detectorParams->numRegionsSbr;
 357   const INT numRegionsOrig    = detectorParams->numRegionsOrig;
 358   const INT numRegionsNrg     = detectorParams->numRegionsNrg;
 359
 360   FIXP_DBL quantStepsSbrTmp[MAX_NUM_REGIONS];
 361   FIXP_DBL quantStepsOrigTmp[MAX_NUM_REGIONS];
 362
 363   /*
 364    Current detector values.
 365    */
 366   FIXP_DBL origQuotaMeanFilt;
 367   FIXP_DBL sbrQuotaMeanFilt;
 368   FIXP_DBL nrg;
 369
 370   /* 0.375 = 3.0 / 8.0; 0.31143075889 = log2(RELAXATION)/64.0; 0.625 = log(16)/64.0; 0.6875 = 44/64.0 */
 371   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 */
 372   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 */
 373   /* If energy is zero then we will get different results for different word lengths. */
 374   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 */
 375
 376   FDKmemcpy(quantStepsSbrTmp,quantStepsSbr,numRegionsSbr*sizeof(FIXP_DBL));
 377   FDKmemcpy(quantStepsOrigTmp,quantStepsOrig,numRegionsOrig*sizeof(FIXP_DBL));
 378
 379   if(*prevRegionSbr < numRegionsSbr)
 380     quantStepsSbrTmp[*prevRegionSbr] = quantStepsSbr[*prevRegionSbr] + hysteresis;
 381   if(*prevRegionSbr > 0)
 382     quantStepsSbrTmp[*prevRegionSbr - 1] = quantStepsSbr[*prevRegionSbr - 1] - hysteresis;
 383
 384   if(*prevRegionOrig < numRegionsOrig)
 385     quantStepsOrigTmp[*prevRegionOrig] = quantStepsOrig[*prevRegionOrig] + hysteresis;
 386   if(*prevRegionOrig > 0)
 387     quantStepsOrigTmp[*prevRegionOrig - 1] = quantStepsOrig[*prevRegionOrig - 1] - hysteresis;
 388
 389   regionSbr  = findRegion(sbrQuotaMeanFilt, quantStepsSbrTmp, numRegionsSbr);
 390   regionOrig = findRegion(origQuotaMeanFilt, quantStepsOrigTmp, numRegionsOrig);
 391   regionNrg  = findRegion(nrg,nrgBorders,numRegionsNrg);
 392
 393   *prevRegionSbr = regionSbr;
 394   *prevRegionOrig = regionOrig;
 395
 396   /* Use different settings if a transient is present*/
 397   invFiltLevel = (transientFlag == 1) ? detectorParams->regionSpaceTransient[regionSbr][regionOrig]
 398                                       : detectorParams->regionSpace[regionSbr][regionOrig];
 399
 400   /* Compensate for low energy.*/
 401   invFiltLevel = max(invFiltLevel + detectorParams->EnergyCompFactor[regionNrg],0);
 402
 403   return (INVF_MODE) (invFiltLevel);
 404 }
 405
 406 /**************************************************************************/
 407 /*!
 408   \brief     Estiamtion of the inverse filtering level required
 409              in the decoder.
 410
 411    A second order LPC is calculated for every filterbank channel, using
 412    the covariance method. THe ratio between the energy of the predicted
 413    signal and the energy of the non-predictable signal is calcualted.
 414
 415   \return    none.
 416
 417 */
 418 /**************************************************************************/
 419 void
 420 FDKsbrEnc_qmfInverseFilteringDetector(HANDLE_SBR_INV_FILT_EST hInvFilt,  /*!< Handle to the SBR_INV_FILT_EST struct. */
 421                             FIXP_DBL **quotaMatrix,            /*!< The matrix holding the tonality values of the original. */
 422                             FIXP_DBL *nrgVector,               /*!< The energy vector. */
 423                             SCHAR    *indexVector,             /*!< Index vector to obtain the patched data. */
 424                             INT startIndex,                    /*!< Start index. */
 425                             INT stopIndex,                     /*!< Stop index. */
 426                             INT transientFlag,                 /*!< Flag indicating if a transient is present or not.*/
 427                             INVF_MODE* infVec                  /*!< Vector holding the inverse filtering levels. */
 428                             )
 429 {
 430   INT band;
 431
 432   /*
 433    * Do the inverse filtering level estimation.
 434    *****************************************************/
 435   for(band = 0 ; band < hInvFilt->noDetectorBands; band++){
 436     INT startChannel = hInvFilt->freqBandTableInvFilt[band];
 437     INT stopChannel  = hInvFilt->freqBandTableInvFilt[band+1];
 438
 439
 440     calculateDetectorValues( quotaMatrix,
 441                              indexVector,
 442                              nrgVector,
 443                             &hInvFilt->detectorValues[band],
 444                              startChannel,
 445                              stopChannel,
 446                              startIndex,
 447                              stopIndex,
 448                              hInvFilt->numberOfStrongest);
 449
 450     infVec[band]= decisionAlgorithm( hInvFilt->detectorParams,
 451                                     &hInvFilt->detectorValues[band],
 452                                      transientFlag,
 453                                     &hInvFilt->prevRegionSbr[band],
 454                                     &hInvFilt->prevRegionOrig[band]);
 455   }
 456
 457 }
 458
 459
 460 /**************************************************************************/
 461 /*!
 462   \brief     Initialize an instance of the inverse filtering level estimator.
 463
 464
 465   \return   errorCode, noError if successful.
 466
 467 */
 468 /**************************************************************************/
 469 INT
 470 FDKsbrEnc_initInvFiltDetector (HANDLE_SBR_INV_FILT_EST hInvFilt,   /*!< Pointer to a handle to the SBR_INV_FILT_EST struct. */
 471                        INT* freqBandTableDetector,          /*!< Frequency band table for the inverse filtering. */
 472                        INT numDetectorBands,                /*!< Number of inverse filtering bands. */
 473                        UINT useSpeechConfig         /*!< Flag: adapt tuning parameters according to speech*/
 474                        )
 475 {
 476   INT i;
 477
 478   FDKmemclear( hInvFilt,sizeof(SBR_INV_FILT_EST));
 479
 480   hInvFilt->detectorParams = (useSpeechConfig) ? &detectorParamsAACSpeech
 481                                                : &detectorParamsAAC ;
 482
 483   hInvFilt->noDetectorBandsMax = numDetectorBands;
 484
 485   /*
 486      Memory initialisation
 487   */
 488   for(i=0;i<hInvFilt->noDetectorBandsMax;i++){
 489     FDKmemclear(&hInvFilt->detectorValues[i], sizeof(DETECTOR_VALUES));
 490     hInvFilt->prevInvfMode[i]   = INVF_OFF;
 491     hInvFilt->prevRegionOrig[i] = 0;
 492     hInvFilt->prevRegionSbr[i]  = 0;
 493   }
 494
 495   /*
 496   Reset the inverse fltering detector.
 497   */
 498   FDKsbrEnc_resetInvFiltDetector(hInvFilt,
 499                        freqBandTableDetector,
 500                        hInvFilt->noDetectorBandsMax);
 501
 502   return (0);
 503 }
 504
 505
 506 /**************************************************************************/
 507 /*!
 508   \brief     resets sbr inverse filtering structure.
 509
 510
 511
 512   \return   errorCode, noError if successful.
 513
 514 */
 515 /**************************************************************************/
 516 INT
 517 FDKsbrEnc_resetInvFiltDetector(HANDLE_SBR_INV_FILT_EST hInvFilt, /*!< Handle to the SBR_INV_FILT_EST struct. */
 518                      INT* freqBandTableDetector,       /*!< Frequency band table for the inverse filtering. */
 519                      INT numDetectorBands)             /*!< Number of inverse filtering bands. */
 520 {
 521
 522   hInvFilt->numberOfStrongest     = 1;
 523   FDKmemcpy(hInvFilt->freqBandTableInvFilt,freqBandTableDetector,(numDetectorBands+1)*sizeof(INT));
 524   hInvFilt->noDetectorBands = numDetectorBands;
 525
 526   return (0);
 527 }
 528
 529