1 /* ----------------------------------------------------------------------------- 2 Software License for The Fraunhofer FDK AAC Codec Library for Android 3 4 Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Frderung 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 (at) 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 130 131 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
