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): M. Lohwasser, M. Gayer
98
99 Description:
100
101 *******************************************************************************/
102
103 #include "fft_rad2.h"
104
105 #include "scramble.h"
106
107 #define __FFT_RAD2_CPP__
108
109 #if defined(__arm__)
110 #include "arm/fft_rad2_arm.cpp"
111
112 #elif defined(__GNUC__) && defined(__mips__) && defined(__mips_dsp)
113 #include "mips/fft_rad2_mips.cpp"
114
115 #endif
116
117 /*****************************************************************************
118
119 functionname: dit_fft (analysis)
120 description: dit-tukey-algorithm
121 scrambles data at entry
122 i.e. loop is made with scrambled data
123 returns:
124 input:
125 output:
126
127 *****************************************************************************/
128
129 #ifndef FUNCTION_dit_fft
130
dit_fft(FIXP_DBL * x,const INT ldn,const FIXP_STP * trigdata,const INT trigDataSize)131 void dit_fft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata,
132 const INT trigDataSize) {
133 const INT n = 1 << ldn;
134 INT trigstep, i, ldm;
135
136 C_ALLOC_ALIGNED_CHECK(x);
137
138 scramble(x, n);
139 /*
140 * 1+2 stage radix 4
141 */
142
143 for (i = 0; i < n * 2; i += 8) {
144 FIXP_DBL a00, a10, a20, a30;
145 a00 = (x[i + 0] + x[i + 2]) >> 1; /* Re A + Re B */
146 a10 = (x[i + 4] + x[i + 6]) >> 1; /* Re C + Re D */
147 a20 = (x[i + 1] + x[i + 3]) >> 1; /* Im A + Im B */
148 a30 = (x[i + 5] + x[i + 7]) >> 1; /* Im C + Im D */
149
150 x[i + 0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */
151 x[i + 4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */
152 x[i + 1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */
153 x[i + 5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */
154
155 a00 = a00 - x[i + 2]; /* Re A - Re B */
156 a10 = a10 - x[i + 6]; /* Re C - Re D */
157 a20 = a20 - x[i + 3]; /* Im A - Im B */
158 a30 = a30 - x[i + 7]; /* Im C - Im D */
159
160 x[i + 2] = a00 + a30; /* Re B' = Re A - Re B + Im C - Im D */
161 x[i + 6] = a00 - a30; /* Re D' = Re A - Re B - Im C + Im D */
162 x[i + 3] = a20 - a10; /* Im B' = Im A - Im B - Re C + Re D */
163 x[i + 7] = a20 + a10; /* Im D' = Im A - Im B + Re C - Re D */
164 }
165
166 for (ldm = 3; ldm <= ldn; ++ldm) {
167 INT m = (1 << ldm);
168 INT mh = (m >> 1);
169 INT j, r;
170
171 trigstep = ((trigDataSize << 2) >> ldm);
172
173 FDK_ASSERT(trigstep > 0);
174
175 /* Do first iteration with c=1.0 and s=0.0 separately to avoid loosing to
176 much precision. Beware: The impact on the overal FFT precision is rather
177 large. */
178 { /* block 1 */
179
180 j = 0;
181
182 for (r = 0; r < n; r += m) {
183 INT t1 = (r + j) << 1;
184 INT t2 = t1 + (mh << 1);
185 FIXP_DBL vr, vi, ur, ui;
186
187 // cplxMultDiv2(&vi, &vr, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
188 vi = x[t2 + 1] >> 1;
189 vr = x[t2] >> 1;
190
191 ur = x[t1] >> 1;
192 ui = x[t1 + 1] >> 1;
193
194 x[t1] = ur + vr;
195 x[t1 + 1] = ui + vi;
196
197 x[t2] = ur - vr;
198 x[t2 + 1] = ui - vi;
199
200 t1 += mh;
201 t2 = t1 + (mh << 1);
202
203 // cplxMultDiv2(&vr, &vi, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
204 vr = x[t2 + 1] >> 1;
205 vi = x[t2] >> 1;
206
207 ur = x[t1] >> 1;
208 ui = x[t1 + 1] >> 1;
209
210 x[t1] = ur + vr;
211 x[t1 + 1] = ui - vi;
212
213 x[t2] = ur - vr;
214 x[t2 + 1] = ui + vi;
215 }
216
217 } /* end of block 1 */
218
219 for (j = 1; j < mh / 4; ++j) {
220 FIXP_STP cs;
221
222 cs = trigdata[j * trigstep];
223
224 for (r = 0; r < n; r += m) {
225 INT t1 = (r + j) << 1;
226 INT t2 = t1 + (mh << 1);
227 FIXP_DBL vr, vi, ur, ui;
228
229 cplxMultDiv2(&vi, &vr, x[t2 + 1], x[t2], cs);
230
231 ur = x[t1] >> 1;
232 ui = x[t1 + 1] >> 1;
233
234 x[t1] = ur + vr;
235 x[t1 + 1] = ui + vi;
236
237 x[t2] = ur - vr;
238 x[t2 + 1] = ui - vi;
239
240 t1 += mh;
241 t2 = t1 + (mh << 1);
242
243 cplxMultDiv2(&vr, &vi, x[t2 + 1], x[t2], cs);
244
245 ur = x[t1] >> 1;
246 ui = x[t1 + 1] >> 1;
247
248 x[t1] = ur + vr;
249 x[t1 + 1] = ui - vi;
250
251 x[t2] = ur - vr;
252 x[t2 + 1] = ui + vi;
253
254 /* Same as above but for t1,t2 with j>mh/4 and thus cs swapped */
255 t1 = (r + mh / 2 - j) << 1;
256 t2 = t1 + (mh << 1);
257
258 cplxMultDiv2(&vi, &vr, x[t2], x[t2 + 1], cs);
259
260 ur = x[t1] >> 1;
261 ui = x[t1 + 1] >> 1;
262
263 x[t1] = ur + vr;
264 x[t1 + 1] = ui - vi;
265
266 x[t2] = ur - vr;
267 x[t2 + 1] = ui + vi;
268
269 t1 += mh;
270 t2 = t1 + (mh << 1);
271
272 cplxMultDiv2(&vr, &vi, x[t2], x[t2 + 1], cs);
273
274 ur = x[t1] >> 1;
275 ui = x[t1 + 1] >> 1;
276
277 x[t1] = ur - vr;
278 x[t1 + 1] = ui - vi;
279
280 x[t2] = ur + vr;
281 x[t2 + 1] = ui + vi;
282 }
283 }
284
285 { /* block 2 */
286 j = mh / 4;
287
288 for (r = 0; r < n; r += m) {
289 INT t1 = (r + j) << 1;
290 INT t2 = t1 + (mh << 1);
291 FIXP_DBL vr, vi, ur, ui;
292
293 cplxMultDiv2(&vi, &vr, x[t2 + 1], x[t2], STC(0x5a82799a),
294 STC(0x5a82799a));
295
296 ur = x[t1] >> 1;
297 ui = x[t1 + 1] >> 1;
298
299 x[t1] = ur + vr;
300 x[t1 + 1] = ui + vi;
301
302 x[t2] = ur - vr;
303 x[t2 + 1] = ui - vi;
304
305 t1 += mh;
306 t2 = t1 + (mh << 1);
307
308 cplxMultDiv2(&vr, &vi, x[t2 + 1], x[t2], STC(0x5a82799a),
309 STC(0x5a82799a));
310
311 ur = x[t1] >> 1;
312 ui = x[t1 + 1] >> 1;
313
314 x[t1] = ur + vr;
315 x[t1 + 1] = ui - vi;
316
317 x[t2] = ur - vr;
318 x[t2 + 1] = ui + vi;
319 }
320 } /* end of block 2 */
321 }
322 }
323
324 #endif
325