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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 Audio Encoder **************************
     85 
     86    author:   M. Werner
     87    contents/description: Convert chaos measure to the tonality index
     88 
     89 ******************************************************************************/
     90 
     91 #include "tonality.h"
     92 #include "chaosmeasure.h"
     93 
     94 static const FIXP_DBL normlog = (FIXP_DBL)0xd977d949; /*FL2FXCONST_DBL(-0.4342944819f * FDKlog(2.0)/FDKlog(2.7182818)); */
     95 
     96 static void FDKaacEnc_CalcSfbTonality(FIXP_DBL      *RESTRICT spectrum,
     97 							INT           *RESTRICT sfbMaxScaleSpec,
     98                             FIXP_DBL      *RESTRICT chaosMeasure,
     99                             FIXP_SGL      *RESTRICT sfbTonality,
    100                             INT           sfbCnt,
    101                             const INT     *RESTRICT sfbOffset,
    102                             FIXP_DBL      *RESTRICT sfbEnergyLD64 );
    103 
    104 
    105 void FDKaacEnc_CalculateFullTonality(FIXP_DBL      *RESTRICT spectrum,
    106 						             INT           *RESTRICT sfbMaxScaleSpec,
    107                                      FIXP_DBL      *RESTRICT sfbEnergyLD64,
    108                                      FIXP_SGL      *RESTRICT sfbTonality,
    109                                      INT            sfbCnt,
    110                                      const INT     *sfbOffset,
    111                                      INT            usePns)
    112 {
    113   INT j;
    114 #if defined(ARCH_PREFER_MULT_32x16)
    115   FIXP_SGL alpha_0 = FL2FXCONST_SGL(0.25f);       /* used in smooth ChaosMeasure */
    116   FIXP_SGL alpha_1 = FL2FXCONST_SGL(1.0f-0.25f);  /* used in smooth ChaosMeasure */
    117 #else
    118   FIXP_DBL alpha_0 = FL2FXCONST_DBL(0.25f);       /* used in smooth ChaosMeasure */
    119   FIXP_DBL alpha_1 = FL2FXCONST_DBL(1.0f-0.25f);  /* used in smooth ChaosMeasure */
    120 #endif
    121   INT numberOfLines = sfbOffset[sfbCnt];
    122 
    123   if (!usePns)
    124     return;
    125 
    126   C_ALLOC_SCRATCH_START(chaosMeasurePerLine, FIXP_DBL, (1024));
    127   /* calculate chaos measure */
    128   FDKaacEnc_CalculateChaosMeasure(spectrum,
    129                         numberOfLines,
    130                         chaosMeasurePerLine);
    131 
    132   /* smooth ChaosMeasure */
    133   for (j=1;j<numberOfLines;j++) {
    134     FIXP_DBL tmp = fMultDiv2(alpha_1, chaosMeasurePerLine[j]);
    135     chaosMeasurePerLine[j] = fMultAdd(tmp, alpha_0, chaosMeasurePerLine[j-1]);
    136   }
    137 
    138   FDKaacEnc_CalcSfbTonality(spectrum,
    139                   sfbMaxScaleSpec,
    140                   chaosMeasurePerLine,
    141                   sfbTonality,
    142                   sfbCnt,
    143                   sfbOffset,
    144                   sfbEnergyLD64);
    145 
    146   C_ALLOC_SCRATCH_END(chaosMeasurePerLine, FIXP_DBL, (1024));
    147 }
    148 
    149 
    150 /*****************************************************************************
    151 
    152     functionname: CalculateTonalityIndex
    153     description:  computes tonality values out of unpredictability values
    154                   limits range and computes log()
    155     returns:
    156     input:        ptr to energies, ptr to chaos measure values,
    157                   number of sfb
    158     output:       sfb wise tonality values
    159 
    160 *****************************************************************************/
    161 static void FDKaacEnc_CalcSfbTonality(FIXP_DBL      *RESTRICT spectrum,
    162                             INT           *RESTRICT sfbMaxScaleSpec,
    163                             FIXP_DBL      *RESTRICT chaosMeasure,
    164                             FIXP_SGL      *RESTRICT sfbTonality,
    165                             INT           sfbCnt,
    166                             const INT     *RESTRICT sfbOffset,
    167                             FIXP_DBL      *RESTRICT sfbEnergyLD64 )
    168 {
    169     INT i, j;
    170 
    171     for (i=0; i<sfbCnt; i++) {
    172       FIXP_DBL chaosMeasureSfbLD64;
    173       INT shiftBits = fixMax(0,sfbMaxScaleSpec[i] - 4);  /* max sfbWidth = 96 ; 2^7=128 => 7/2 = 4 (spc*spc) */
    174 
    175       FIXP_DBL chaosMeasureSfb = FL2FXCONST_DBL(0.0);
    176 
    177       /* calc chaosMeasurePerSfb */
    178       for (j=(sfbOffset[i+1]-sfbOffset[i])-1; j>=0; j--) {
    179         FIXP_DBL tmp = (*spectrum++)<<shiftBits;
    180         FIXP_DBL lineNrg = fMultDiv2(tmp, tmp);
    181         chaosMeasureSfb = fMultAddDiv2(chaosMeasureSfb, lineNrg, *chaosMeasure++);
    182       }
    183 
    184       /* calc tonalityPerSfb */
    185       if (chaosMeasureSfb != FL2FXCONST_DBL(0.0))
    186       {
    187         /* add ld(convtone)/64 and 2/64 bec.fMultDiv2 */
    188         chaosMeasureSfbLD64 = CalcLdData((chaosMeasureSfb)) - sfbEnergyLD64[i];
    189         chaosMeasureSfbLD64 += FL2FXCONST_DBL(3.0f/64) - ((FIXP_DBL)(shiftBits)<<(DFRACT_BITS-6));
    190 
    191         if (chaosMeasureSfbLD64 > FL2FXCONST_DBL(-0.0519051) )     /* > ld(0.05)+ld(2) */
    192         {
    193           if (chaosMeasureSfbLD64 <= FL2FXCONST_DBL(0.0) )
    194 		    sfbTonality[i] = FX_DBL2FX_SGL(fMultDiv2( chaosMeasureSfbLD64 , normlog ) << 7);
    195           else
    196             sfbTonality[i] = FL2FXCONST_SGL(0.0);
    197         }
    198         else
    199           sfbTonality[i] = (FIXP_SGL)MAXVAL_SGL;
    200       }
    201       else
    202         sfbTonality[i] = (FIXP_SGL)MAXVAL_SGL;
    203     }
    204 }
    205