libFDK/include/FDK_trigFcts.h

   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.
  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@iis.fraunhofer.de
  82 ----------------------------------------------------------------------------------------------------------- */
  83
  84 /***************************  Fraunhofer IIS FDK Tools  **********************
  85
  86    Author(s):   Haricharan Lakshman, Manuel Jander
  87    Description: Trigonometric functions fixed point fractional implementation.
  88
  89 ******************************************************************************/
  90
  91
  92
  93 #include "common_fix.h"
  94
  95 #include "FDK_tools_rom.h"
  96
  97 /* Fixed point precision definitions */
  98 #define Q(format)        ((FIXP_DBL)(((LONG)1) << (format)))
  99
 100 #ifndef M_PI
 101 #define M_PI      (3.14159265358979323846f)
 102 #endif
 103
 104 /*!
 105  * Inverse tangent function.
 106  */
 107
 108 // --- fixp_atan() ----
 109 #define Q_ATANINP   (25)    // Input in q25, Output in q30
 110 #define Q_ATANOUT   (30)
 111 #define ATI_SF              ((DFRACT_BITS-1)-Q_ATANINP)  // 6
 112 #define ATI_SCALE           ((float)(1<<ATI_SF))         //
 113 #define ATO_SF              ((DFRACT_BITS-1)-Q_ATANOUT)  // 1   ] -pi/2 .. pi/2 [
 114 #define ATO_SCALE           ((float)(1<<ATO_SF))         //
 115 // --- fixp_atan2() ---
 116 #define Q_ATAN2OUT  (29)
 117 #define AT2O_SF             ((DFRACT_BITS-1)-Q_ATAN2OUT) // 2   ] -pi   .. pi   ]
 118 #define AT2O_SCALE          ((float)(1<<AT2O_SF))        //
 119 // --------------------
 120
 121 FIXP_DBL fixp_atan(FIXP_DBL x);
 122 FIXP_DBL fixp_atan2(FIXP_DBL y, FIXP_DBL x);
 123
 124 FIXP_DBL fixp_cos(FIXP_DBL x, int scale);
 125 FIXP_DBL fixp_sin(FIXP_DBL x, int scale);
 126
 127 #define FIXP_COS_SIN
 128
 129
 130 #include "FDK_tools_rom.h"
 131
 132 #define SINETAB SineTable512
 133 #define LD 9
 134
 135
 136 #ifndef FUNCTION_inline_fixp_cos_sin
 137
 138 #define FUNCTION_inline_fixp_cos_sin
 139
 140 /*
 141  * Calculates coarse lookup index and sign for sine.
 142  * Returns delta x residual.
 143  */
 144 static inline FIXP_DBL fixp_sin_cos_residual_inline(FIXP_DBL x, int scale, FIXP_DBL *sine, FIXP_DBL *cosine)
 145 {
 146     FIXP_DBL residual;
 147     int s;
 148     int shift = (31-scale-LD-1);
 149     int ssign = 1;
 150     int csign = 1;
 151
 152     residual = fMult(x, FL2FXCONST_DBL(1.0/M_PI));
 153     s = ((LONG)residual) >> shift;
 154
 155     residual &= ( (1<<shift) - 1 );
 156     residual = fMult(residual, FL2FXCONST_DBL(M_PI/4.0)) << 2;
 157     residual <<= scale;
 158
 159     /* Sine sign symmetry */
 160     if (s & ((1<<LD)<<1) ) {
 161       ssign = -ssign;
 162     }
 163     /* Cosine sign symmetry */
 164     if ( (s + (1<<LD)) & ((1<<LD)<<1) ) {
 165       csign = -csign;
 166     }
 167
 168     s = fAbs(s);
 169
 170     s &= (((1<<LD)<<1)-1); /* Modulo PI */
 171
 172     if (s > (1<<LD)) {
 173       s = ((1<<LD)<<1) - s;
 174     }
 175
 176     {
 177       LONG sl, cl;
 178       /* Because of packed table */
 179       if (s > (1<<(LD-1))) {
 180         FIXP_STP tmp;
 181         /* Cosine/Sine simetry for angles greater than PI/4 */
 182         s = (1<<LD)-s;
 183         tmp = SINETAB[s];
 184         sl = (LONG)tmp.v.re;
 185         cl = (LONG)tmp.v.im;
 186       } else {
 187         FIXP_STP tmp;
 188         tmp = SINETAB[s];
 189         sl = (LONG)tmp.v.im;
 190         cl = (LONG)tmp.v.re;
 191       }
 192
 193 #ifdef SINETABLE_16BIT
 194       *sine   = (FIXP_DBL)((sl * ssign) << (DFRACT_BITS-FRACT_BITS));
 195       *cosine = (FIXP_DBL)((cl * csign) << (DFRACT_BITS-FRACT_BITS));
 196 #else
 197       *sine   = (FIXP_DBL)(sl * ssign);
 198       *cosine = (FIXP_DBL)(cl * csign);
 199 #endif
 200     }
 201
 202     return residual;
 203 }
 204
 205 /**
 206  * \brief Calculate cosine and sine value each of 2 angles different angle values.
 207  * \param x1 first angle value
 208  * \param x2 second angle value
 209  * \param scale exponent of x1 and x2
 210  * \param out pointer to 4 FIXP_DBL locations, were the values cos(x1), sin(x1), cos(x2), sin(x2)
 211  *            will be stored into.
 212  */
 213 static inline void inline_fixp_cos_sin (FIXP_DBL x1, FIXP_DBL x2, const int scale, FIXP_DBL *out)
 214 {
 215     FIXP_DBL residual, error0, error1, sine, cosine;
 216     residual = fixp_sin_cos_residual_inline(x1, scale, &sine, &cosine);
 217     error0 = fMultDiv2(sine, residual);
 218     error1 = fMultDiv2(cosine, residual);
 219     *out++  = cosine - (error0<<1);
 220     *out++  = sine   + (error1<<1);
 221
 222     residual = fixp_sin_cos_residual_inline(x2, scale, &sine, &cosine);
 223     error0 = fMultDiv2(sine, residual);
 224     error1 = fMultDiv2(cosine, residual);
 225     *out++  = cosine - (error0<<1);
 226     *out++  = sine   + (error1<<1);
 227 }
 228 #endif
 229