1
2 /* -----------------------------------------------------------------------------------------------------------
3 Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5 � Copyright 1995 - 2012 Fraunhofer-Gesellschaft zur F�rderung 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):
87 Description: dit_fft ARM assembler replacements.
88
89 ******************************************************************************/
90
91 /* NEON optimized FFT currently builds only with RVCT toolchain */
92
93 #ifndef FUNCTION_dit_fft
94
95 /* If dit_fft was not yet defined by ARM-Cortex ... */
96
97 #if defined(SINETABLE_16BIT)
98
99 #define FUNCTION_dit_fft
100
101 /*****************************************************************************
102
103 date: 28.07.2005 srl
104
105 Contents/description: dit-tukey-FFT-algorithm
106
107 ******************************************************************************/
108
109 #if defined(FUNCTION_dit_fft)
110
111
dit_fft(FIXP_DBL * x,const INT ldn,const FIXP_STP * trigdata,const INT trigDataSize)112 void dit_fft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata, const INT trigDataSize)
113 {
114 const INT n=1<<ldn;
115 INT i;
116
117 scramble(x,n);
118 /*
119 * 1+2 stage radix 4
120 */
121
122 for (i=0;i<n*2;i+=8)
123 {
124 FIXP_DBL a00, a10, a20, a30;
125 a00 = (x[i + 0] + x[i + 2])>>1; /* Re A + Re B */
126 a10 = (x[i + 4] + x[i + 6])>>1; /* Re C + Re D */
127 a20 = (x[i + 1] + x[i + 3])>>1; /* Im A + Im B */
128 a30 = (x[i + 5] + x[i + 7])>>1; /* Im C + Im D */
129
130 x[i + 0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */
131 x[i + 4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */
132 x[i + 1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */
133 x[i + 5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */
134
135 a00 = a00 - x[i + 2]; /* Re A - Re B */
136 a10 = a10 - x[i + 6]; /* Re C - Re D */
137 a20 = a20 - x[i + 3]; /* Im A - Im B */
138 a30 = a30 - x[i + 7]; /* Im C - Im D */
139
140 x[i + 2] = a00 + a30; /* Re B' = Re A - Re B + Im C - Im D */
141 x[i + 6] = a00 - a30; /* Re D' = Re A - Re B - Im C + Im D */
142 x[i + 3] = a20 - a10; /* Im B' = Im A - Im B - Re C + Re D */
143 x[i + 7] = a20 + a10; /* Im D' = Im A - Im B + Re C - Re D */
144 }
145
146 INT mh = 1 << 1;
147 INT ldm = ldn - 2;
148 INT trigstep = trigDataSize;
149
150 do
151 {
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 much precision.
161 Beware: The impact on the overal FFT precision is rather large. */
162 {
163 FIXP_DBL *xt1 = x;
164 int r = n;
165
166 do {
167 FIXP_DBL *xt2 = xt1 + (mh<<1);
168 /*
169 FIXP_DBL *xt1 = x+ ((r)<<1);
170 FIXP_DBL *xt2 = xt1 + (mh<<1);
171 */
172 FIXP_DBL vr,vi,ur,ui;
173
174 //cplxMultDiv2(&vi, &vr, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
175 vi = xt2[1]>>1;
176 vr = xt2[0]>>1;
177
178 ur = xt1[0]>>1;
179 ui = xt1[1]>>1;
180
181 xt1[0] = ur+vr;
182 xt1[1] = ui+vi;
183
184 xt2[0] = ur-vr;
185 xt2[1] = ui-vi;
186
187 xt1 += mh;
188 xt2 += mh;
189
190 //cplxMultDiv2(&vr, &vi, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
191 vr = xt2[1]>>1;
192 vi = xt2[0]>>1;
193
194 ur = xt1[0]>>1;
195 ui = xt1[1]>>1;
196
197 xt1[0] = ur+vr;
198 xt1[1] = ui-vi;
199
200 xt2[0] = ur-vr;
201 xt2[1] = ui+vi;
202
203 xt1 = xt2 + mh;
204 } while ((r=r-(mh<<1)) != 0);
205 }
206 for(j=4; j<mh; j+=4)
207 {
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 {
217 FIXP_DBL *xt2 = xt1 + (mh<<1);
218 FIXP_DBL vr,vi,ur,ui;
219
220 cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], cs);
221
222 ur = xt1[0]>>1;
223 ui = xt1[1]>>1;
224
225 xt1[0] = ur+vr;
226 xt1[1] = ui+vi;
227
228 xt2[0] = ur-vr;
229 xt2[1] = ui-vi;
230
231 xt1 += mh;
232 xt2 += mh;
233
234 cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], cs);
235
236 ur = xt1[0]>>1;
237 ui = xt1[1]>>1;
238
239 xt1[0] = ur+vr;
240 xt1[1] = ui-vi;
241
242 xt2[0] = ur-vr;
243 xt2[1] = ui+vi;
244
245 /* Same as above but for t1,t2 with j>mh/4 and thus cs swapped */
246 xt1 = xt1 - (j);
247 xt2 = xt1 + (mh<<1);
248
249 cplxMultDiv2(&vi, &vr, xt2[0], xt2[1], cs);
250
251 ur = xt1[0]>>1;
252 ui = xt1[1]>>1;
253
254 xt1[0] = ur+vr;
255 xt1[1] = ui-vi;
256
257 xt2[0] = ur-vr;
258 xt2[1] = ui+vi;
259
260 xt1 += mh;
261 xt2 += mh;
262
263 cplxMultDiv2(&vr, &vi, xt2[0], xt2[1], cs);
264
265 ur = xt1[0]>>1;
266 ui = xt1[1]>>1;
267
268 xt1[0] = ur-vr;
269 xt1[1] = ui-vi;
270
271 xt2[0] = ur+vr;
272 xt2[1] = ui+vi;
273
274 xt1 = xt2 + (j);
275 } while ((r=r-(mh<<1)) != 0);
276 }
277 {
278 FIXP_DBL *xt1 = x + (mh>>1);
279 int r = n;
280
281 do
282 {
283 FIXP_DBL *xt2 = xt1 + (mh<<1);
284 FIXP_DBL vr,vi,ur,ui;
285
286 cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], STC(0x5a82799a), STC(0x5a82799a));
287
288 ur = xt1[0]>>1;
289 ui = xt1[1]>>1;
290
291 xt1[0] = ur+vr;
292 xt1[1] = ui+vi;
293
294 xt2[0] = ur-vr;
295 xt2[1] = ui-vi;
296
297 xt1 += mh;
298 xt2 += mh;
299
300 cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], STC(0x5a82799a), 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