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      1 /* -----------------------------------------------------------------------------
      2 Software License for The Fraunhofer FDK AAC Codec Library for Android
      3 
      4  Copyright  1995 - 2018 Fraunhofer-Gesellschaft zur Frderung der angewandten
      5 Forschung e.V. All rights reserved.
      6 
      7  1.    INTRODUCTION
      8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
      9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
     10 scheme for digital audio. This FDK AAC Codec software is intended to be used on
     11 a wide variety of Android devices.
     12 
     13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
     14 general perceptual audio codecs. AAC-ELD is considered the best-performing
     15 full-bandwidth communications codec by independent studies and is widely
     16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG
     17 specifications.
     18 
     19 Patent licenses for necessary patent claims for the FDK AAC Codec (including
     20 those of Fraunhofer) may be obtained through Via Licensing
     21 (www.vialicensing.com) or through the respective patent owners individually for
     22 the purpose of encoding or decoding bit streams in products that are compliant
     23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
     24 Android devices already license these patent claims through Via Licensing or
     25 directly from the patent owners, and therefore FDK AAC Codec software may
     26 already be covered under those patent licenses when it is used for those
     27 licensed purposes only.
     28 
     29 Commercially-licensed AAC software libraries, including floating-point versions
     30 with enhanced sound quality, are also available from Fraunhofer. Users are
     31 encouraged to check the Fraunhofer website for additional applications
     32 information and documentation.
     33 
     34 2.    COPYRIGHT LICENSE
     35 
     36 Redistribution and use in source and binary forms, with or without modification,
     37 are permitted without payment of copyright license fees provided that you
     38 satisfy the following conditions:
     39 
     40 You must retain the complete text of this software license in redistributions of
     41 the FDK AAC Codec or your modifications thereto in source code form.
     42 
     43 You must retain the complete text of this software license in the documentation
     44 and/or other materials provided with redistributions of the FDK AAC Codec or
     45 your modifications thereto in binary form. You must make available free of
     46 charge copies of the complete source code of the FDK AAC Codec and your
     47 modifications thereto to recipients of copies in binary form.
     48 
     49 The name of Fraunhofer may not be used to endorse or promote products derived
     50 from this library without prior written permission.
     51 
     52 You may not charge copyright license fees for anyone to use, copy or distribute
     53 the FDK AAC Codec software or your modifications thereto.
     54 
     55 Your modified versions of the FDK AAC Codec must carry prominent notices stating
     56 that you changed the software and the date of any change. For modified versions
     57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
     58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
     59 AAC Codec Library for Android."
     60 
     61 3.    NO PATENT LICENSE
     62 
     63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
     64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
     65 Fraunhofer provides no warranty of patent non-infringement with respect to this
     66 software.
     67 
     68 You may use this FDK AAC Codec software or modifications thereto only for
     69 purposes that are authorized by appropriate patent licenses.
     70 
     71 4.    DISCLAIMER
     72 
     73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
     74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
     75 including but not limited to the implied warranties of merchantability and
     76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
     77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
     78 or consequential damages, including but not limited to procurement of substitute
     79 goods or services; loss of use, data, or profits, or business interruption,
     80 however caused and on any theory of liability, whether in contract, strict
     81 liability, or tort (including negligence), arising in any way out of the use of
     82 this software, even if advised of the possibility of such damage.
     83 
     84 5.    CONTACT INFORMATION
     85 
     86 Fraunhofer Institute for Integrated Circuits IIS
     87 Attention: Audio and Multimedia Departments - FDK AAC LL
     88 Am Wolfsmantel 33
     89 91058 Erlangen, Germany
     90 
     91 www.iis.fraunhofer.de/amm
     92 amm-info (at) iis.fraunhofer.de
     93 ----------------------------------------------------------------------------- */
     94 
     95 /**************************** AAC encoder library ******************************
     96 
     97    Author(s):   Tobias Chalupka
     98 
     99    Description: FDKaacLdEnc_MdctTransform480:
    100                 The module FDKaacLdEnc_MdctTransform will perform the MDCT.
    101                 The MDCT supports the sine window and
    102                 the zero padded window. The algorithm of the MDCT
    103                 can be divided in  Windowing, PreModulation, Fft and
    104                 PostModulation.
    105 
    106 *******************************************************************************/
    107 
    108 #include "transform.h"
    109 #include "dct.h"
    110 #include "psy_const.h"
    111 #include "aacEnc_rom.h"
    112 #include "FDK_tools_rom.h"
    113 
    114 #if defined(__arm__)
    115 #endif
    116 
    117 INT FDKaacEnc_Transform_Real(const INT_PCM *pTimeData,
    118                              FIXP_DBL *RESTRICT mdctData, const INT blockType,
    119                              const INT windowShape, INT *prevWindowShape,
    120                              H_MDCT mdctPers, const INT frameLength,
    121                              INT *pMdctData_e, INT filterType) {
    122   const INT_PCM *RESTRICT timeData;
    123 
    124   UINT numSpec;
    125   UINT numMdctLines;
    126   UINT offset;
    127   int fr; /* fr: right window slope length */
    128   SHORT mdctData_e[8];
    129 
    130   timeData = pTimeData;
    131 
    132   if (blockType == SHORT_WINDOW) {
    133     numSpec = 8;
    134     numMdctLines = frameLength >> 3;
    135   } else {
    136     numSpec = 1;
    137     numMdctLines = frameLength;
    138   }
    139 
    140   offset = (windowShape == LOL_WINDOW) ? ((frameLength * 3) >> 2) : 0;
    141   switch (blockType) {
    142     case LONG_WINDOW:
    143     case STOP_WINDOW:
    144       fr = frameLength - offset;
    145       break;
    146     case START_WINDOW: /* or StopStartSequence */
    147     case SHORT_WINDOW:
    148       fr = frameLength >> 3;
    149       break;
    150     default:
    151       FDK_ASSERT(0);
    152       return -1;
    153   }
    154 
    155   mdct_block(mdctPers, timeData, frameLength, mdctData, numSpec, numMdctLines,
    156              FDKgetWindowSlope(fr, windowShape), fr, mdctData_e);
    157 
    158   if (blockType == SHORT_WINDOW) {
    159     if (!(mdctData_e[0] == mdctData_e[1] && mdctData_e[1] == mdctData_e[2] &&
    160           mdctData_e[2] == mdctData_e[3] && mdctData_e[3] == mdctData_e[4] &&
    161           mdctData_e[4] == mdctData_e[5] && mdctData_e[5] == mdctData_e[6] &&
    162           mdctData_e[6] == mdctData_e[7])) {
    163       return -1;
    164     }
    165   }
    166   *prevWindowShape = windowShape;
    167   *pMdctData_e = mdctData_e[0];
    168 
    169   return 0;
    170 }
    171 
    172 INT FDKaacEnc_Transform_Real_Eld(const INT_PCM *pTimeData,
    173                                  FIXP_DBL *RESTRICT mdctData,
    174                                  const INT blockType, const INT windowShape,
    175                                  INT *prevWindowShape, const INT frameLength,
    176                                  INT *mdctData_e, INT filterType,
    177                                  FIXP_DBL *RESTRICT overlapAddBuffer) {
    178   const INT_PCM *RESTRICT timeData;
    179 
    180   INT i;
    181 
    182   /* tl: transform length
    183      fl: left window slope length
    184      nl: left window slope offset
    185      fr: right window slope length
    186      nr: right window slope offset */
    187   const FIXP_WTB *pWindowELD = NULL;
    188   int N = frameLength;
    189   int L = frameLength;
    190 
    191   timeData = pTimeData;
    192 
    193   if (blockType != LONG_WINDOW) {
    194     return -1;
    195   }
    196 
    197   /*
    198    * MDCT scale:
    199    * + 1: fMultDiv2() in windowing.
    200    * + 1: Because of factor 1/2 in Princen-Bradley compliant windowed TDAC.
    201    */
    202   *mdctData_e = 1 + 1;
    203 
    204   switch (frameLength) {
    205     case 512:
    206       pWindowELD = ELDAnalysis512;
    207       break;
    208     case 480:
    209       pWindowELD = ELDAnalysis480;
    210       break;
    211     case 256:
    212       pWindowELD = ELDAnalysis256;
    213       *mdctData_e += 1;
    214       break;
    215     case 240:
    216       pWindowELD = ELDAnalysis240;
    217       *mdctData_e += 1;
    218       break;
    219     case 128:
    220       pWindowELD = ELDAnalysis128;
    221       *mdctData_e += 2;
    222       break;
    223     case 120:
    224       pWindowELD = ELDAnalysis120;
    225       *mdctData_e += 2;
    226       break;
    227     default:
    228       FDK_ASSERT(0);
    229       return -1;
    230   }
    231 
    232   for (i = 0; i < N / 4; i++) {
    233     FIXP_DBL z0, outval;
    234 
    235     z0 = (fMult((FIXP_PCM)timeData[L + N * 3 / 4 - 1 - i],
    236                 pWindowELD[N / 2 - 1 - i])
    237           << (WTS0 - 1)) +
    238          (fMult((FIXP_PCM)timeData[L + N * 3 / 4 + i], pWindowELD[N / 2 + i])
    239           << (WTS0 - 1));
    240 
    241     outval = (fMultDiv2((FIXP_PCM)timeData[L + N * 3 / 4 - 1 - i],
    242                         pWindowELD[N + N / 2 - 1 - i]) >>
    243               (-WTS1));
    244     outval += (fMultDiv2((FIXP_PCM)timeData[L + N * 3 / 4 + i],
    245                          pWindowELD[N + N / 2 + i]) >>
    246                (-WTS1));
    247     outval += (fMultDiv2(overlapAddBuffer[N / 2 + i], pWindowELD[2 * N + i]) >>
    248                (-WTS2 - 1));
    249 
    250     overlapAddBuffer[N / 2 + i] = overlapAddBuffer[i];
    251 
    252     overlapAddBuffer[i] = z0;
    253     mdctData[i] = overlapAddBuffer[N / 2 + i] +
    254                   (fMultDiv2(overlapAddBuffer[N + N / 2 - 1 - i],
    255                              pWindowELD[2 * N + N / 2 + i]) >>
    256                    (-WTS2 - 1));
    257 
    258     mdctData[N - 1 - i] = outval;
    259     overlapAddBuffer[N + N / 2 - 1 - i] = outval;
    260   }
    261 
    262   for (i = N / 4; i < N / 2; i++) {
    263     FIXP_DBL z0, outval;
    264 
    265     z0 = fMult((FIXP_PCM)timeData[L + N * 3 / 4 - 1 - i],
    266                pWindowELD[N / 2 - 1 - i])
    267          << (WTS0 - 1);
    268 
    269     outval = (fMultDiv2((FIXP_PCM)timeData[L + N * 3 / 4 - 1 - i],
    270                         pWindowELD[N + N / 2 - 1 - i]) >>
    271               (-WTS1));
    272     outval += (fMultDiv2(overlapAddBuffer[N / 2 + i], pWindowELD[2 * N + i]) >>
    273                (-WTS2 - 1));
    274 
    275     overlapAddBuffer[N / 2 + i] =
    276         overlapAddBuffer[i] +
    277         (fMult((FIXP_PCM)timeData[L - N / 4 + i], pWindowELD[N / 2 + i])
    278          << (WTS0 - 1));
    279 
    280     overlapAddBuffer[i] = z0;
    281     mdctData[i] = overlapAddBuffer[N / 2 + i] +
    282                   (fMultDiv2(overlapAddBuffer[N + N / 2 - 1 - i],
    283                              pWindowELD[2 * N + N / 2 + i]) >>
    284                    (-WTS2 - 1));
    285 
    286     mdctData[N - 1 - i] = outval;
    287     overlapAddBuffer[N + N / 2 - 1 - i] = outval;
    288   }
    289   dct_IV(mdctData, frameLength, mdctData_e);
    290 
    291   *prevWindowShape = windowShape;
    292 
    293   return 0;
    294 }
    295