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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 Förderung 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@iis.fraunhofer.de
93 ----------------------------------------------------------------------------- */
94 
95 /******************* Library for basic calculation routines ********************
96 
97    Author(s):
98 
99    Description: dit_fft ARM assembler replacements.
100 
101 *******************************************************************************/
102 
103 #ifndef __FFT_RAD2_CPP__
104 #error \
105     "Do not compile this file separately. It is included on demand from fft_rad2.cpp"
106 #endif
107 
108 #ifndef FUNCTION_dit_fft
109 #if defined(SINETABLE_16BIT)
110 
111 #define FUNCTION_dit_fft
112 #if defined(FUNCTION_dit_fft)
113 
dit_fft(FIXP_DBL * x,const INT ldn,const FIXP_STP * trigdata,const INT trigDataSize)114 void dit_fft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata,
115              const INT trigDataSize) {
116   const INT n = 1 << ldn;
117   INT i;
118 
119   scramble(x, n);
120   /*
121    * 1+2 stage radix 4
122    */
123 
124   for (i = 0; i < n * 2; i += 8) {
125     FIXP_DBL a00, a10, a20, a30;
126     a00 = (x[i + 0] + x[i + 2]) >> 1; /* Re A + Re B */
127     a10 = (x[i + 4] + x[i + 6]) >> 1; /* Re C + Re D */
128     a20 = (x[i + 1] + x[i + 3]) >> 1; /* Im A + Im B */
129     a30 = (x[i + 5] + x[i + 7]) >> 1; /* Im C + Im D */
130 
131     x[i + 0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */
132     x[i + 4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */
133     x[i + 1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */
134     x[i + 5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */
135 
136     a00 = a00 - x[i + 2]; /* Re A - Re B */
137     a10 = a10 - x[i + 6]; /* Re C - Re D */
138     a20 = a20 - x[i + 3]; /* Im A - Im B */
139     a30 = a30 - x[i + 7]; /* Im C - Im D */
140 
141     x[i + 2] = a00 + a30; /* Re B' = Re A - Re B + Im C - Im D */
142     x[i + 6] = a00 - a30; /* Re D' = Re A - Re B - Im C + Im D */
143     x[i + 3] = a20 - a10; /* Im B' = Im A - Im B - Re C + Re D */
144     x[i + 7] = a20 + a10; /* Im D' = Im A - Im B + Re C - Re D */
145   }
146 
147   INT mh = 1 << 1;
148   INT ldm = ldn - 2;
149   INT trigstep = trigDataSize;
150 
151   do {
152     const FIXP_STP *pTrigData = trigdata;
153     INT j;
154 
155     mh <<= 1;
156     trigstep >>= 1;
157 
158     FDK_ASSERT(trigstep > 0);
159 
160     /* Do first iteration with c=1.0 and s=0.0 separately to avoid loosing to
161        much precision. Beware: The impact on the overal FFT precision is rather
162        large. */
163     {
164       FIXP_DBL *xt1 = x;
165       int r = n;
166 
167       do {
168         FIXP_DBL *xt2 = xt1 + (mh << 1);
169         /*
170         FIXP_DBL *xt1 = x+ ((r)<<1);
171         FIXP_DBL *xt2 = xt1 + (mh<<1);
172         */
173         FIXP_DBL vr, vi, ur, ui;
174 
175         // cplxMultDiv2(&vi, &vr, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
176         vi = xt2[1] >> 1;
177         vr = xt2[0] >> 1;
178 
179         ur = xt1[0] >> 1;
180         ui = xt1[1] >> 1;
181 
182         xt1[0] = ur + vr;
183         xt1[1] = ui + vi;
184 
185         xt2[0] = ur - vr;
186         xt2[1] = ui - vi;
187 
188         xt1 += mh;
189         xt2 += mh;
190 
191         // cplxMultDiv2(&vr, &vi, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
192         vr = xt2[1] >> 1;
193         vi = xt2[0] >> 1;
194 
195         ur = xt1[0] >> 1;
196         ui = xt1[1] >> 1;
197 
198         xt1[0] = ur + vr;
199         xt1[1] = ui - vi;
200 
201         xt2[0] = ur - vr;
202         xt2[1] = ui + vi;
203 
204         xt1 = xt2 + mh;
205       } while ((r = r - (mh << 1)) != 0);
206     }
207     for (j = 4; j < mh; j += 4) {
208       FIXP_DBL *xt1 = x + (j >> 1);
209       FIXP_SPK cs;
210       int r = n;
211 
212       pTrigData += trigstep;
213       cs = *pTrigData;
214 
215       do {
216         FIXP_DBL *xt2 = xt1 + (mh << 1);
217         FIXP_DBL vr, vi, ur, ui;
218 
219         cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], cs);
220 
221         ur = xt1[0] >> 1;
222         ui = xt1[1] >> 1;
223 
224         xt1[0] = ur + vr;
225         xt1[1] = ui + vi;
226 
227         xt2[0] = ur - vr;
228         xt2[1] = ui - vi;
229 
230         xt1 += mh;
231         xt2 += mh;
232 
233         cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], cs);
234 
235         ur = xt1[0] >> 1;
236         ui = xt1[1] >> 1;
237 
238         xt1[0] = ur + vr;
239         xt1[1] = ui - vi;
240 
241         xt2[0] = ur - vr;
242         xt2[1] = ui + vi;
243 
244         /* Same as above but for t1,t2 with j>mh/4 and thus cs swapped */
245         xt1 = xt1 - (j);
246         xt2 = xt1 + (mh << 1);
247 
248         cplxMultDiv2(&vi, &vr, xt2[0], xt2[1], cs);
249 
250         ur = xt1[0] >> 1;
251         ui = xt1[1] >> 1;
252 
253         xt1[0] = ur + vr;
254         xt1[1] = ui - vi;
255 
256         xt2[0] = ur - vr;
257         xt2[1] = ui + vi;
258 
259         xt1 += mh;
260         xt2 += mh;
261 
262         cplxMultDiv2(&vr, &vi, xt2[0], xt2[1], cs);
263 
264         ur = xt1[0] >> 1;
265         ui = xt1[1] >> 1;
266 
267         xt1[0] = ur - vr;
268         xt1[1] = ui - vi;
269 
270         xt2[0] = ur + vr;
271         xt2[1] = ui + vi;
272 
273         xt1 = xt2 + (j);
274       } while ((r = r - (mh << 1)) != 0);
275     }
276     {
277       FIXP_DBL *xt1 = x + (mh >> 1);
278       int r = n;
279 
280       do {
281         FIXP_DBL *xt2 = xt1 + (mh << 1);
282         FIXP_DBL vr, vi, ur, ui;
283 
284         cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], STC(0x5a82799a),
285                      STC(0x5a82799a));
286 
287         ur = xt1[0] >> 1;
288         ui = xt1[1] >> 1;
289 
290         xt1[0] = ur + vr;
291         xt1[1] = ui + vi;
292 
293         xt2[0] = ur - vr;
294         xt2[1] = ui - vi;
295 
296         xt1 += mh;
297         xt2 += mh;
298 
299         cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], STC(0x5a82799a),
300                      STC(0x5a82799a));
301 
302         ur = xt1[0] >> 1;
303         ui = xt1[1] >> 1;
304 
305         xt1[0] = ur + vr;
306         xt1[1] = ui - vi;
307 
308         xt2[0] = ur - vr;
309         xt2[1] = ui + vi;
310 
311         xt1 = xt2 + mh;
312       } while ((r = r - (mh << 1)) != 0);
313     }
314   } while (--ldm != 0);
315 }
316 
317 #endif /* if defined(FUNCTION_dit_fft)  */
318 
319 #endif /* if defined(SINETABLE_16BIT) */
320 
321 #endif /* ifndef FUNCTION_dit_fft */
322