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      1 
      2 /* -----------------------------------------------------------------------------------------------------------
      3 Software License for The Fraunhofer FDK AAC Codec Library for Android
      4 
      5  Copyright  1995 - 2012 Fraunhofer-Gesellschaft zur Frderung 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.
     36 
     37 You must retain the complete text of this software license in the documentation and/or other materials
     38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
     39 You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
     40 modifications thereto to recipients of copies in binary form.
     41 
     42 The name of Fraunhofer may not be used to endorse or promote products derived from this library without
     43 prior written permission.
     44 
     45 You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
     46 software or your modifications thereto.
     47 
     48 Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
     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,
     69 or business interruption, however caused and on any theory of liability, whether in contract, strict
     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 (at) iis.fraunhofer.de
     82 ----------------------------------------------------------------------------------------------------------- */
     83 
     84 /*****************************  MPEG-4 AAC Decoder  **************************
     85 
     86    Author(s):   Josef Hoepfl
     87    Description: long/short-block decoding
     88 
     89 ******************************************************************************/
     90 
     91 #include "block.h"
     92 
     93 #include "aac_rom.h"
     94 #include "FDK_bitstream.h"
     95 #include "FDK_tools_rom.h"
     96 
     97 
     98 
     99 
    100 #include "aacdec_hcr.h"
    101 #include "rvlc.h"
    102 
    103 
    104 #if defined(__arm__)
    105 #include "arm/block_arm.cpp"
    106 #endif
    107 
    108 /*!
    109   \brief Read escape sequence of codeword
    110 
    111   The function reads the escape sequence from the bitstream,
    112   if the absolute value of the quantized coefficient has the
    113   value 16.
    114 
    115   \return  quantized coefficient
    116 */
    117 LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */
    118                      const LONG q)        /*!< quantized coefficient */
    119 {
    120   LONG i, off, neg ;
    121 
    122   if (q < 0)
    123   {
    124     if (q != -16) return q;
    125     neg = 1;
    126   }
    127   else
    128   {
    129     if (q != +16) return q;
    130     neg = 0;
    131   }
    132 
    133   for (i=4; ; i++)
    134   {
    135     if (FDKreadBits(bs,1) == 0)
    136       break;
    137   }
    138 
    139   if (i > 16)
    140   {
    141     if (i - 16 > CACHE_BITS) { /* cannot read more than "CACHE_BITS" bits at once in the function FDKreadBits() */
    142       return (MAX_QUANTIZED_VALUE + 1); /* returning invalid value that will be captured later */
    143     }
    144 
    145     off = FDKreadBits(bs,i-16) << 16;
    146     off |= FDKreadBits(bs,16);
    147   }
    148   else
    149   {
    150     off = FDKreadBits(bs,i);
    151   }
    152 
    153   i = off + (1 << i);
    154 
    155   if (neg) i = -i;
    156 
    157   return i;
    158 }
    159 
    160 AAC_DECODER_ERROR CBlock_ReadScaleFactorData(
    161         CAacDecoderChannelInfo *pAacDecoderChannelInfo,
    162         HANDLE_FDK_BITSTREAM bs,
    163         UINT flags
    164         )
    165 {
    166   int temp;
    167   int band;
    168   int group;
    169   int position = 0; /* accu for intensity delta coding */
    170   int factor = pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain; /* accu for scale factor delta coding */
    171   UCHAR *pCodeBook = pAacDecoderChannelInfo->pDynData->aCodeBook;
    172   SHORT *pScaleFactor = pAacDecoderChannelInfo->pDynData->aScaleFactor;
    173   const CodeBookDescription *hcb =&AACcodeBookDescriptionTable[BOOKSCL];
    174 
    175   int ScaleFactorBandsTransmitted = GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo);
    176   for (group=0; group < GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); group++)
    177   {
    178     for (band=0; band < ScaleFactorBandsTransmitted; band++)
    179     {
    180       switch (pCodeBook[group*16+band]) {
    181 
    182       case ZERO_HCB: /* zero book */
    183         pScaleFactor[group*16+band] = 0;
    184         break;
    185 
    186       default: /* decode scale factor */
    187         {
    188           temp = CBlock_DecodeHuffmanWord(bs,hcb);
    189           factor += temp - 60; /* MIDFAC 1.5 dB */
    190         }
    191         pScaleFactor[group*16+band] = factor - 100;
    192         break;
    193 
    194       case INTENSITY_HCB: /* intensity steering */
    195       case INTENSITY_HCB2:
    196         temp = CBlock_DecodeHuffmanWord(bs,hcb);
    197         position += temp - 60;
    198         pScaleFactor[group*16+band] = position - 100;
    199         break;
    200 
    201       case NOISE_HCB: /* PNS */
    202         if (flags & (AC_MPS_RES|AC_USAC|AC_RSVD50)) {
    203           return AAC_DEC_PARSE_ERROR;
    204         }
    205         CPns_Read( &pAacDecoderChannelInfo->data.aac.PnsData, bs, hcb, pAacDecoderChannelInfo->pDynData->aScaleFactor, pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain, band, group);
    206         break;
    207       }
    208     }
    209   }
    210 
    211   return AAC_DEC_OK;
    212 }
    213 
    214 void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo)
    215 {
    216   int band;
    217   int window;
    218   const SHORT * RESTRICT pSfbScale  = pAacDecoderChannelInfo->pDynData->aSfbScale;
    219   SHORT * RESTRICT pSpecScale = pAacDecoderChannelInfo->specScale;
    220   int groupwin,group;
    221   const SHORT * RESTRICT BandOffsets = GetScaleFactorBandOffsets(&pAacDecoderChannelInfo->icsInfo, pSamplingRateInfo);
    222   SPECTRAL_PTR RESTRICT pSpectralCoefficient = pAacDecoderChannelInfo->pSpectralCoefficient;
    223 
    224 
    225   FDKmemclear(pSpecScale, 8*sizeof(SHORT));
    226 
    227   int max_band = GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo);
    228   for (window=0, group=0; group < GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); group++)
    229   {
    230     for (groupwin=0; groupwin < GetWindowGroupLength(&pAacDecoderChannelInfo->icsInfo,group); groupwin++, window++)
    231     {
    232       int SpecScale_window = pSpecScale[window];
    233       FIXP_DBL *pSpectrum = SPEC(pSpectralCoefficient, window,  pAacDecoderChannelInfo->granuleLength);
    234 
    235       /* find scaling for current window */
    236       for (band=0; band < max_band; band++)
    237       {
    238         SpecScale_window = fMax(SpecScale_window, (int)pSfbScale[window*16+band]);
    239       }
    240 
    241       if (pAacDecoderChannelInfo->pDynData->TnsData.Active) {
    242         SpecScale_window += TNS_SCALE;
    243       }
    244 
    245       /* store scaling of current window */
    246       pSpecScale[window] = SpecScale_window;
    247 
    248 #ifdef FUNCTION_CBlock_ScaleSpectralData_func1
    249 
    250       CBlock_ScaleSpectralData_func1(pSpectrum, max_band, BandOffsets, SpecScale_window, pSfbScale, window);
    251 
    252 #else /* FUNCTION_CBlock_ScaleSpectralData_func1 */
    253       for (band=0; band < max_band; band++)
    254       {
    255         int scale = SpecScale_window - pSfbScale[window*16+band];
    256         if (scale)
    257         {
    258           /* following relation can be used for optimizations: (BandOffsets[i]%4) == 0 for all i */
    259           int max_index = BandOffsets[band+1];
    260           for (int index = BandOffsets[band]; index < max_index; index++)
    261           {
    262             pSpectrum[index] >>= scale;
    263           }
    264         }
    265       }
    266 #endif  /* FUNCTION_CBlock_ScaleSpectralData_func1 */
    267     }
    268   }
    269 
    270 }
    271 
    272 AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs,
    273                                          CAacDecoderChannelInfo *pAacDecoderChannelInfo,
    274                                          const SamplingRateInfo *pSamplingRateInfo,
    275                                          const UINT  flags)
    276 {
    277   int top, band;
    278   int sect_len, sect_len_incr;
    279   int group;
    280   UCHAR sect_cb;
    281   UCHAR *pCodeBook = pAacDecoderChannelInfo->pDynData->aCodeBook;
    282   /* HCR input (long) */
    283   SHORT *pNumLinesInSec    = pAacDecoderChannelInfo->pDynData->specificTo.aac.aNumLineInSec4Hcr;
    284   int    numLinesInSecIdx  = 0;
    285   UCHAR *pHcrCodeBook      = pAacDecoderChannelInfo->pDynData->specificTo.aac.aCodeBooks4Hcr;
    286   const SHORT *BandOffsets = GetScaleFactorBandOffsets(&pAacDecoderChannelInfo->icsInfo, pSamplingRateInfo);
    287   pAacDecoderChannelInfo->pDynData->specificTo.aac.numberSection = 0;
    288   AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
    289 
    290   FDKmemclear(pCodeBook, sizeof(UCHAR)*(8*16));
    291 
    292   const int nbits = (IsLongBlock(&pAacDecoderChannelInfo->icsInfo) == 1) ? 5 : 3;
    293 
    294   int sect_esc_val = (1 << nbits) - 1 ;
    295 
    296   UCHAR ScaleFactorBandsTransmitted = GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo);
    297   for (group=0; group<GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); group++)
    298   {
    299     for (band=0; band < ScaleFactorBandsTransmitted; )
    300     {
    301       sect_len = 0;
    302       if ( flags & AC_ER_VCB11 )  {
    303         sect_cb = (UCHAR) FDKreadBits(bs,5);
    304       }
    305       else
    306         sect_cb = (UCHAR) FDKreadBits(bs,4);
    307 
    308       if ( ((flags & AC_ER_VCB11) == 0) || ( sect_cb < 11 ) || ((sect_cb > 11) && (sect_cb < 16)) ) {
    309         sect_len_incr = FDKreadBits(bs, nbits);
    310         while (sect_len_incr == sect_esc_val)
    311         {
    312           sect_len += sect_esc_val;
    313           sect_len_incr = FDKreadBits(bs, nbits);
    314         }
    315       }
    316       else {
    317         sect_len_incr = 1;
    318       }
    319 
    320       sect_len += sect_len_incr;
    321 
    322 
    323       top = band + sect_len;
    324 
    325       if (flags & AC_ER_HCR) {
    326         /* HCR input (long) -- collecting sideinfo (for HCR-_long_ only) */
    327         pNumLinesInSec[numLinesInSecIdx] = BandOffsets[top] - BandOffsets[band];
    328         numLinesInSecIdx++;
    329         if (numLinesInSecIdx >= MAX_SFB_HCR) {
    330           return AAC_DEC_PARSE_ERROR;
    331         }
    332         if (
    333              (sect_cb == BOOKSCL) )
    334         {
    335           return AAC_DEC_INVALID_CODE_BOOK;
    336         } else {
    337           *pHcrCodeBook++ = sect_cb;
    338         }
    339         pAacDecoderChannelInfo->pDynData->specificTo.aac.numberSection++;
    340       }
    341 
    342       /* Check spectral line limits */
    343       if (IsLongBlock( &(pAacDecoderChannelInfo->icsInfo) ))
    344       {
    345         if (top > 64) {
    346           return AAC_DEC_DECODE_FRAME_ERROR;
    347         }
    348       } else { /* short block */
    349         if (top + group*16 > (8 * 16)) {
    350           return AAC_DEC_DECODE_FRAME_ERROR;
    351         }
    352       }
    353 
    354       /* Check if decoded codebook index is feasible */
    355       if ( (sect_cb == BOOKSCL)
    356        || ( (sect_cb == INTENSITY_HCB || sect_cb == INTENSITY_HCB2) && pAacDecoderChannelInfo->pDynData->RawDataInfo.CommonWindow == 0)
    357          )
    358       {
    359         return AAC_DEC_INVALID_CODE_BOOK;
    360       }
    361 
    362       /* Store codebook index */
    363       for (; band < top; band++)
    364       {
    365         pCodeBook[group*16+band] = sect_cb;
    366       }
    367     }
    368   }
    369 
    370 
    371   return ErrorStatus;
    372 }
    373 
    374 /* mso: provides a faster way to i-quantize a whole band in one go */
    375 
    376 /**
    377  * \brief inverse quantize one sfb. Each value of the sfb is processed according to the
    378  *        formula: spectrum[i] = Sign(spectrum[i]) * Matissa(spectrum[i])^(4/3) * 2^(lsb/4).
    379  * \param spectrum pointer to first line of the sfb to be inverse quantized.
    380  * \param noLines number of lines belonging to the sfb.
    381  * \param lsb last 2 bits of the scale factor of the sfb.
    382  * \param scale max allowed shift scale for the sfb.
    383  */
    384 static
    385 void InverseQuantizeBand( FIXP_DBL * RESTRICT spectrum,
    386                               INT noLines,
    387                               INT lsb,
    388                               INT scale )
    389 {
    390     const FIXP_DBL * RESTRICT InverseQuantTabler=(FIXP_DBL *)InverseQuantTable;
    391     const FIXP_DBL * RESTRICT MantissaTabler=(FIXP_DBL *)MantissaTable[lsb];
    392     const SCHAR* RESTRICT ExponentTabler=(SCHAR*)ExponentTable[lsb];
    393 
    394     FIXP_DBL *ptr = spectrum;
    395     FIXP_DBL signedValue;
    396 
    397     FDK_ASSERT(noLines>2);
    398     for (INT i=noLines; i--; )
    399     {
    400         if ((signedValue = *ptr++) != FL2FXCONST_DBL(0))
    401         {
    402           FIXP_DBL value = fAbs(signedValue);
    403           UINT freeBits = CntLeadingZeros(value);
    404           UINT exponent = 32 - freeBits;
    405 
    406           UINT x = (UINT) (LONG)value << (INT) freeBits;
    407           x <<= 1;                                  /* shift out sign bit to avoid masking later on */
    408           UINT tableIndex = x >> 24;
    409           x = (x >> 20) &  0x0F;
    410 
    411           UINT r0=(UINT)(LONG)InverseQuantTabler[tableIndex+0];
    412           UINT r1=(UINT)(LONG)InverseQuantTabler[tableIndex+1];
    413           UINT temp= (r1 - r0)*x + (r0 << 4);
    414 
    415           value = fMultDiv2((FIXP_DBL)temp, MantissaTabler[exponent]);
    416 
    417           /* + 1 compensates fMultDiv2() */
    418           scaleValueInPlace(&value, scale + ExponentTabler[exponent] + 1);
    419 
    420           signedValue = (signedValue < (FIXP_DBL)0) ? -value : value;
    421           ptr[-1] = signedValue;
    422         }
    423     }
    424 }
    425 
    426 AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo)
    427 {
    428   int window, group, groupwin, band;
    429   int ScaleFactorBandsTransmitted = GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo);
    430   UCHAR *RESTRICT pCodeBook = pAacDecoderChannelInfo->pDynData->aCodeBook;
    431   SHORT *RESTRICT pSfbScale = pAacDecoderChannelInfo->pDynData->aSfbScale;
    432   SHORT *RESTRICT pScaleFactor = pAacDecoderChannelInfo->pDynData->aScaleFactor;
    433   const SHORT *RESTRICT BandOffsets = GetScaleFactorBandOffsets(&pAacDecoderChannelInfo->icsInfo, pSamplingRateInfo);
    434 
    435   FDKmemclear(pAacDecoderChannelInfo->pDynData->aSfbScale, (8*16)*sizeof(SHORT));
    436 
    437   for (window=0, group=0; group < GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); group++)
    438   {
    439     for (groupwin=0; groupwin < GetWindowGroupLength(&pAacDecoderChannelInfo->icsInfo,group); groupwin++, window++)
    440     {
    441       /* inverse quantization */
    442       for (band=0; band < ScaleFactorBandsTransmitted; band++)
    443       {
    444         FIXP_DBL *pSpectralCoefficient = SPEC(pAacDecoderChannelInfo->pSpectralCoefficient, window, pAacDecoderChannelInfo->granuleLength) + BandOffsets[band];
    445 
    446         int noLines = BandOffsets[band+1] - BandOffsets[band];
    447         int bnds = group*16+band;
    448         int i;
    449 
    450         if ((pCodeBook[bnds] == ZERO_HCB)
    451          || (pCodeBook[bnds] == INTENSITY_HCB)
    452          || (pCodeBook[bnds] == INTENSITY_HCB2)
    453            )
    454           continue;
    455 
    456         if (pCodeBook[bnds] == NOISE_HCB)
    457         {
    458           /* Leave headroom for PNS values. + 1 because ceil(log2(2^(0.25*3))) = 1,
    459              worst case of additional headroom required because of the scalefactor. */
    460           pSfbScale[window*16+band] = (pScaleFactor [bnds] >> 2) + 1 ;
    461           continue;
    462         }
    463 
    464         /* Find max spectral line value of the current sfb */
    465         FIXP_DBL locMax = (FIXP_DBL)0;
    466 
    467         for (i = noLines; i-- ; ) {
    468           /* Expensive memory access */
    469           locMax = fMax(fixp_abs(pSpectralCoefficient[i]), locMax);
    470         }
    471 
    472         /* Cheap robustness improvement - Do not remove!!! */
    473         if (fixp_abs(locMax) > (FIXP_DBL)MAX_QUANTIZED_VALUE) {
    474           return AAC_DEC_DECODE_FRAME_ERROR;
    475         }
    476 
    477         /*
    478            The inverse quantized spectral lines are defined by:
    479         pSpectralCoefficient[i] = Sign(pSpectralCoefficient[i]) * 2^(0.25*pScaleFactor[bnds]) * pSpectralCoefficient[i]^(4/3)
    480            This is equivalent to:
    481         pSpectralCoefficient[i]    = Sign(pSpectralCoefficient[i]) * (2^(pScaleFactor[bnds] % 4) * pSpectralCoefficient[i]^(4/3))
    482         pSpectralCoefficient_e[i] += pScaleFactor[bnds]/4
    483         */
    484         {
    485           int msb = pScaleFactor [bnds] >> 2 ;
    486           int lsb = pScaleFactor [bnds] & 0x03 ;
    487 
    488           int scale = GetScaleFromValue(locMax, lsb);
    489 
    490           pSfbScale[window*16+band] = msb - scale;
    491           InverseQuantizeBand(pSpectralCoefficient, noLines, lsb, scale);
    492         }
    493       }
    494     }
    495   }
    496 
    497 
    498   return AAC_DEC_OK;
    499 }
    500 
    501 
    502 AAC_DECODER_ERROR  CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs,
    503                                            CAacDecoderChannelInfo *pAacDecoderChannelInfo,
    504                                            const SamplingRateInfo *pSamplingRateInfo,
    505                                            const UINT  flags)
    506 {
    507   int i,index;
    508   int window,group,groupwin,groupoffset,band;
    509   UCHAR *RESTRICT pCodeBook = pAacDecoderChannelInfo->pDynData->aCodeBook;
    510   const SHORT *RESTRICT BandOffsets = GetScaleFactorBandOffsets(&pAacDecoderChannelInfo->icsInfo, pSamplingRateInfo);
    511 
    512   SPECTRAL_PTR pSpectralCoefficient = pAacDecoderChannelInfo->pSpectralCoefficient;
    513   FIXP_DBL locMax;
    514 
    515   int ScaleFactorBandsTransmitted = GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo);
    516 
    517   FDK_ASSERT(BandOffsets != NULL);
    518 
    519   FDKmemclear(pSpectralCoefficient, sizeof(SPECTRUM));
    520 
    521   if ( (flags & AC_ER_HCR) == 0 )
    522   {
    523     groupoffset = 0;
    524 
    525     /* plain huffman decoder  short */
    526     for (group=0; group < GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); group++)
    527     {
    528       for (band=0; band < ScaleFactorBandsTransmitted; band++)
    529       {
    530         int bnds = group*16+band;
    531         UCHAR currentCB = pCodeBook[bnds];
    532 
    533         /* patch to run plain-huffman-decoder with vcb11 input codebooks (LAV-checking might be possible below using the virtual cb and a LAV-table) */
    534         if ((currentCB >= 16) && (currentCB <= 31)) {
    535           pCodeBook[bnds] = currentCB = 11;
    536         }
    537         if ( !((currentCB == ZERO_HCB)
    538             || (currentCB == NOISE_HCB)
    539             || (currentCB == INTENSITY_HCB)
    540             || (currentCB == INTENSITY_HCB2)) )
    541         {
    542           const CodeBookDescription *hcb = &AACcodeBookDescriptionTable[currentCB];
    543           int step = hcb->Dimension;
    544           int offset = hcb->Offset;
    545           int bits = hcb->numBits;
    546           int mask = (1<<bits)-1;
    547 
    548           for (groupwin=0; groupwin < GetWindowGroupLength(&pAacDecoderChannelInfo->icsInfo,group); groupwin++)
    549           {
    550             window = groupoffset + groupwin;
    551 
    552             FIXP_DBL *mdctSpectrum = SPEC(pSpectralCoefficient, window, pAacDecoderChannelInfo->granuleLength);
    553 
    554             locMax = (FIXP_DBL)0 ;
    555 
    556             for (index=BandOffsets[band]; index < BandOffsets[band+1]; index+=step)
    557             {
    558               int idx = CBlock_DecodeHuffmanWord(bs,hcb);
    559 
    560               for (i=0; i<step; i++) {
    561                 FIXP_DBL tmp;
    562 
    563                 tmp = (FIXP_DBL)((idx & mask)-offset);
    564                 idx >>= bits;
    565 
    566                 if (offset == 0) {
    567                   if (tmp != FIXP_DBL(0))
    568                     tmp = (FDKreadBits(bs,1))? -tmp : tmp;
    569                 }
    570                 mdctSpectrum[index+i] = tmp;
    571               }
    572 
    573               if (currentCB == ESCBOOK)
    574               {
    575                 mdctSpectrum[index+0] = (FIXP_DBL)CBlock_GetEscape(bs, (LONG)mdctSpectrum[index+0]);
    576                 mdctSpectrum[index+1] = (FIXP_DBL)CBlock_GetEscape(bs, (LONG)mdctSpectrum[index+1]);
    577 
    578               }
    579             }
    580           }
    581         }
    582       }
    583       groupoffset += GetWindowGroupLength(&pAacDecoderChannelInfo->icsInfo,group);
    584     }
    585     /* plain huffman decoding (short) finished */
    586   }
    587   /* HCR - Huffman Codeword Reordering  short */
    588   else  /* if ( flags & AC_ER_HCR ) */
    589   {
    590     H_HCR_INFO hHcr = &pAacDecoderChannelInfo->pComData->overlay.aac.erHcrInfo;
    591     int hcrStatus = 0;
    592     int hcrConcealWholeFrame = 0;
    593 
    594     /* advanced Huffman decoding starts here (HCR decoding :) */
    595     if ( pAacDecoderChannelInfo->pDynData->specificTo.aac.lenOfReorderedSpectralData != 0 ) {
    596 
    597       /* HCR initialization short */
    598       hcrStatus = HcrInit(hHcr, pAacDecoderChannelInfo, pSamplingRateInfo, bs);
    599 
    600       if (hcrStatus != 0) {
    601 #if HCR_ERROR_CONCEALMENT
    602         hcrConcealWholeFrame = 1;
    603         return AAC_DEC_DECODE_FRAME_ERROR;  /* concealment is muting in the first step, therefore return now */
    604         // hcr decoding is not skipped because of returning above
    605 #else
    606         return AAC_DEC_DECODE_FRAME_ERROR;
    607 #endif
    608       }
    609 
    610       /* HCR decoding short */
    611       hcrStatus = HcrDecoder(hHcr, pAacDecoderChannelInfo, pSamplingRateInfo, bs);
    612 
    613 
    614 #if HCR_ERROR_CONCEALMENT
    615       HcrMuteErroneousLines(hHcr);
    616 #else
    617       return AAC_DEC_DECODE_FRAME_ERROR;
    618 #endif /* HCR_ERROR_CONCEALMENT */
    619 
    620       FDKpushFor (bs, pAacDecoderChannelInfo->pDynData->specificTo.aac.lenOfReorderedSpectralData);
    621     }
    622   }
    623   /* HCR - Huffman Codeword Reordering short finished */
    624 
    625 
    626 
    627   if ( IsLongBlock(&pAacDecoderChannelInfo->icsInfo) && !(flags & (AC_ELD|AC_SCALABLE)) )
    628   {
    629     /* apply pulse data */
    630     CPulseData_Apply(&pAacDecoderChannelInfo->pDynData->specificTo.aac.PulseData,
    631                       GetScaleFactorBandOffsets(&pAacDecoderChannelInfo->icsInfo, pSamplingRateInfo),
    632                       SPEC_LONG(pSpectralCoefficient));
    633   }
    634 
    635 
    636   return AAC_DEC_OK;
    637 }
    638 
    639 
    640 
    641 void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[],
    642                   const SamplingRateInfo *pSamplingRateInfo,
    643                   const UINT flags,
    644                   const int channel )
    645 {
    646 
    647   if ( !(flags & (AC_USAC|AC_RSVD50|AC_MPS_RES)) ) {
    648     CPns_Apply(
    649            &pAacDecoderChannelInfo[channel]->data.aac.PnsData,
    650            &pAacDecoderChannelInfo[channel]->icsInfo,
    651             pAacDecoderChannelInfo[channel]->pSpectralCoefficient,
    652             pAacDecoderChannelInfo[channel]->specScale,
    653             pAacDecoderChannelInfo[channel]->pDynData->aScaleFactor,
    654             pSamplingRateInfo,
    655             pAacDecoderChannelInfo[channel]->granuleLength,
    656             channel
    657             );
    658   }
    659 
    660   CTns_Apply (
    661          &pAacDecoderChannelInfo[channel]->pDynData->TnsData,
    662          &pAacDecoderChannelInfo[channel]->icsInfo,
    663           pAacDecoderChannelInfo[channel]->pSpectralCoefficient,
    664           pSamplingRateInfo,
    665           pAacDecoderChannelInfo[channel]->granuleLength
    666           );
    667 }
    668 
    669 static
    670 int getWindow2Nr(int length, int shape)
    671 {
    672   int nr = 0;
    673 
    674   if (shape == 2) {
    675     /* Low Overlap, 3/4 zeroed */
    676     nr = (length * 3)>>2;
    677   }
    678 
    679   return nr;
    680 }
    681 
    682 void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
    683                             CAacDecoderChannelInfo *pAacDecoderChannelInfo,
    684                             INT_PCM outSamples[],
    685                             const SHORT frameLen,
    686                             const int stride,
    687                             const int frameOk,
    688                             FIXP_DBL *pWorkBuffer1 )
    689 {
    690   int fr, fl, tl, nSamples, nSpec;
    691 
    692   /* Determine left slope length (fl), right slope length (fr) and transform length (tl).
    693      USAC: The slope length may mismatch with the previous frame in case of LPD / FD
    694            transitions. The adjustment is handled by the imdct implementation.
    695   */
    696   tl = frameLen;
    697   nSpec = 1;
    698 
    699   switch( pAacDecoderChannelInfo->icsInfo.WindowSequence ) {
    700     default:
    701     case OnlyLongSequence:
    702       fl = frameLen;
    703       fr = frameLen - getWindow2Nr(frameLen, GetWindowShape(&pAacDecoderChannelInfo->icsInfo));
    704       break;
    705     case LongStopSequence:
    706       fl = frameLen >> 3;
    707       fr = frameLen;
    708       break;
    709     case LongStartSequence: /* or StopStartSequence */
    710       fl = frameLen;
    711       fr = frameLen >> 3;
    712       break;
    713     case EightShortSequence:
    714       fl = fr = frameLen >> 3;
    715       tl >>= 3;
    716       nSpec = 8;
    717       break;
    718   }
    719 
    720   {
    721     int i;
    722 
    723     {
    724       FIXP_DBL *tmp = pAacDecoderChannelInfo->pComData->workBufferCore1->mdctOutTemp;
    725 
    726       nSamples = imdct_block(
    727              &pAacDecoderStaticChannelInfo->IMdct,
    728               tmp,
    729               SPEC_LONG(pAacDecoderChannelInfo->pSpectralCoefficient),
    730               pAacDecoderChannelInfo->specScale,
    731               nSpec,
    732               frameLen,
    733               tl,
    734               FDKgetWindowSlope(fl, GetWindowShape(&pAacDecoderChannelInfo->icsInfo)),
    735               fl,
    736               FDKgetWindowSlope(fr, GetWindowShape(&pAacDecoderChannelInfo->icsInfo)),
    737               fr,
    738               (FIXP_DBL)0 );
    739 
    740       for (i=0; i<frameLen; i++) {
    741         outSamples[i*stride] = IMDCT_SCALE(tmp[i]);
    742       }
    743     }
    744   }
    745 
    746   FDK_ASSERT(nSamples == frameLen);
    747 
    748 }
    749 
    750 #include "ldfiltbank.h"
    751 void CBlock_FrequencyToTimeLowDelay( CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
    752                                      CAacDecoderChannelInfo *pAacDecoderChannelInfo,
    753                                      INT_PCM outSamples[],
    754                                      const short frameLen,
    755                                      const char stride )
    756 {
    757   InvMdctTransformLowDelay_fdk (
    758           SPEC_LONG(pAacDecoderChannelInfo->pSpectralCoefficient),
    759           pAacDecoderChannelInfo->specScale[0],
    760           outSamples,
    761           pAacDecoderStaticChannelInfo->pOverlapBuffer,
    762           stride,
    763           frameLen
    764           );
    765 }
    766