1
2/* -----------------------------------------------------------------------------------------------------------
3Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5� Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6  All rights reserved.
7
8 1.    INTRODUCTION
9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12
13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16of the MPEG specifications.
17
18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20individually for the purpose of encoding or decoding bit streams in products that are compliant with
21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23software may already be covered under those patent licenses when it is used for those licensed purposes only.
24
25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27applications information and documentation.
28
292.    COPYRIGHT LICENSE
30
31Redistribution and use in source and binary forms, with or without modification, are permitted without
32payment of copyright license fees provided that you satisfy the following conditions:
33
34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35your modifications thereto in source code form.
36
37You must retain the complete text of this software license in the documentation and/or other materials
38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40modifications thereto to recipients of copies in binary form.
41
42The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43prior written permission.
44
45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46software or your modifications thereto.
47
48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49and 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
533.    NO PATENT LICENSE
54
55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57respect to this software.
58
59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60by appropriate patent licenses.
61
624.    DISCLAIMER
63
64This 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
66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69or business interruption, however caused and on any theory of liability, whether in contract, strict
70liability, or tort (including negligence), arising in any way out of the use of this software, even if
71advised of the possibility of such damage.
72
735.    CONTACT INFORMATION
74
75Fraunhofer Institute for Integrated Circuits IIS
76Attention: Audio and Multimedia Departments - FDK AAC LL
77Am Wolfsmantel 33
7891058 Erlangen, Germany
79
80www.iis.fraunhofer.de/amm
81amm-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
121FIXP_DBL fixp_atan(FIXP_DBL x);
122FIXP_DBL fixp_atan2(FIXP_DBL y, FIXP_DBL x);
123
124FIXP_DBL fixp_cos(FIXP_DBL x, int scale);
125FIXP_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 */
144static 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 */
213static 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
230