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 /*********************** MPEG surround decoder library ************************* 96 97 Author(s): Matthias Hildenbrand 98 99 Description: USAC MPS212 Transient Steering Decorrelator (TSD) 100 101 *******************************************************************************/ 102 103 #include "sac_tsd.h" 104 105 #define TSD_START_BAND (7) 106 #define SIZE_S (4) 107 #define SIZE_C (5) 108 109 /*** Tables ***/ 110 RAM_ALIGN 111 LNK_SECTION_CONSTDATA 112 static const UCHAR nBitsTsdCW_32slots[32] = { 113 5, 9, 13, 16, 18, 20, 22, 24, 25, 26, 27, 28, 29, 29, 30, 30, 114 30, 29, 29, 28, 27, 26, 25, 24, 22, 20, 18, 16, 13, 9, 5, 0}; 115 116 RAM_ALIGN 117 LNK_SECTION_CONSTDATA 118 static const UCHAR nBitsTsdCW_64slots[64] = { 119 6, 11, 16, 20, 23, 27, 30, 33, 35, 38, 40, 42, 44, 46, 48, 49, 120 51, 52, 53, 55, 56, 57, 58, 58, 59, 60, 60, 60, 61, 61, 61, 61, 121 61, 61, 61, 60, 60, 60, 59, 58, 58, 57, 56, 55, 53, 52, 51, 49, 122 48, 46, 44, 42, 40, 38, 35, 33, 30, 27, 23, 20, 16, 11, 6, 0}; 123 124 RAM_ALIGN 125 LNK_SECTION_CONSTDATA 126 static const FIXP_STP phiTsd[8] = { 127 STCP(0x7fffffff, 0x00000000), STCP(0x5a82799a, 0x5a82799a), 128 STCP(0x00000000, 0x7fffffff), STCP(0xa57d8666, 0x5a82799a), 129 STCP(0x80000000, 0x00000000), STCP(0xa57d8666, 0xa57d8666), 130 STCP(0x00000000, 0x80000000), STCP(0x5a82799a, 0xa57d8666), 131 }; 132 133 /*** Static Functions ***/ 134 static void longmult1(USHORT a[], USHORT b, USHORT d[], int len) { 135 int k; 136 ULONG tmp; 137 ULONG b0 = (ULONG)b; 138 139 tmp = ((ULONG)a[0]) * b0; 140 d[0] = (USHORT)tmp; 141 142 for (k = 1; k < len; k++) { 143 tmp = (tmp >> 16) + ((ULONG)a[k]) * b0; 144 d[k] = (USHORT)tmp; 145 } 146 } 147 148 static void longdiv(USHORT b[], USHORT a, USHORT d[], USHORT *pr, int len) { 149 ULONG r; 150 ULONG tmp; 151 int k; 152 153 FDK_ASSERT(a != 0); 154 155 r = 0; 156 157 for (k = len - 1; k >= 0; k--) { 158 tmp = ((ULONG)b[k]) + (r << 16); 159 160 if (tmp) { 161 d[k] = (USHORT)(tmp / a); 162 r = tmp - d[k] * a; 163 } else { 164 d[k] = 0; 165 } 166 } 167 *pr = (USHORT)r; 168 } 169 170 static void longsub(USHORT a[], USHORT b[], int lena, int lenb) { 171 int h; 172 LONG carry = 0; 173 174 FDK_ASSERT(lena >= lenb); 175 for (h = 0; h < lenb; h++) { 176 carry += ((LONG)a[h]) - ((LONG)b[h]); 177 a[h] = (USHORT)carry; 178 carry = carry >> 16; 179 } 180 181 for (; h < lena; h++) { 182 carry = ((LONG)a[h]) + carry; 183 a[h] = (USHORT)carry; 184 carry = carry >> 16; 185 } 186 187 FDK_ASSERT(carry == 188 0); /* carry != 0 indicates subtraction underflow, e.g. b > a */ 189 return; 190 } 191 192 static int longcompare(USHORT a[], USHORT b[], int len) { 193 int i; 194 195 for (i = len - 1; i > 0; i--) { 196 if (a[i] != b[i]) break; 197 } 198 return (a[i] >= b[i]) ? 1 : 0; 199 } 200 201 FDK_INLINE int isTrSlot(const TSD_DATA *pTsdData, const int ts) { 202 return (pTsdData->bsTsdTrPhaseData[ts] >= 0); 203 } 204 205 /*** Public Functions ***/ 206 int TsdRead(HANDLE_FDK_BITSTREAM hBs, const int numSlots, TSD_DATA *pTsdData) { 207 int nBitsTrSlots = 0; 208 int bsTsdNumTrSlots; 209 const UCHAR *nBitsTsdCW_tab = NULL; 210 211 switch (numSlots) { 212 case 32: 213 nBitsTrSlots = 4; 214 nBitsTsdCW_tab = nBitsTsdCW_32slots; 215 break; 216 case 64: 217 nBitsTrSlots = 5; 218 nBitsTsdCW_tab = nBitsTsdCW_64slots; 219 break; 220 default: 221 return 1; 222 } 223 224 /*** Read TempShapeData for bsTempShapeConfig == 3 ***/ 225 pTsdData->bsTsdEnable = FDKreadBit(hBs); 226 if (!pTsdData->bsTsdEnable) { 227 return 0; 228 } 229 230 /*** Parse/Decode TsdData() ***/ 231 pTsdData->numSlots = numSlots; 232 233 bsTsdNumTrSlots = FDKreadBits(hBs, nBitsTrSlots); 234 235 /* Decode transient slot positions */ 236 { 237 int nBitsTsdCW = (int)nBitsTsdCW_tab[bsTsdNumTrSlots]; 238 SCHAR *phaseData = pTsdData->bsTsdTrPhaseData; 239 int p = bsTsdNumTrSlots + 1; 240 int k, h; 241 USHORT s[SIZE_S] = {0}; 242 USHORT c[SIZE_C] = {0}; 243 USHORT r[1]; 244 245 /* Init with TsdSepData[k] = 0 */ 246 for (k = 0; k < numSlots; k++) { 247 phaseData[k] = -1; /* means TsdSepData[] = 0 */ 248 } 249 250 for (h = (SIZE_S - 1); h >= 0; h--) { 251 if (nBitsTsdCW > h * 16) { 252 s[h] = (USHORT)FDKreadBits(hBs, nBitsTsdCW - h * 16); 253 nBitsTsdCW = h * 16; 254 } 255 } 256 257 /* c = prod_{h=1}^{p} (k-p+h)/h */ 258 k = numSlots - 1; 259 c[0] = k - p + 1; 260 for (h = 2; h <= p; h++) { 261 longmult1(c, (k - p + h), c, 5); /* c *= k - p + h; */ 262 longdiv(c, h, c, r, 5); /* c /= h; */ 263 FDK_ASSERT(*r == 0); 264 } 265 266 /* go through all slots */ 267 for (; k >= 0; k--) { 268 if (p > k) { 269 for (; k >= 0; k--) { 270 phaseData[k] = 1; /* means TsdSepData[] = 1 */ 271 } 272 break; 273 } 274 if (longcompare(s, c, 4)) { /* (s >= c) */ 275 longsub(s, c, 4, 4); /* s -= c; */ 276 phaseData[k] = 1; /* means TsdSepData[] = 1 */ 277 if (p == 1) { 278 break; 279 } 280 /* Update c for next iteration: c_new = c_old * p / k */ 281 longmult1(c, p, c, 5); 282 p--; 283 } else { 284 /* Update c for next iteration: c_new = c_old * (k-p) / k */ 285 longmult1(c, (k - p), c, 5); 286 } 287 longdiv(c, k, c, r, 5); 288 FDK_ASSERT(*r == 0); 289 } 290 291 /* Read phase data */ 292 for (k = 0; k < numSlots; k++) { 293 if (phaseData[k] == 1) { 294 phaseData[k] = FDKreadBits(hBs, 3); 295 } 296 } 297 } 298 299 return 0; 300 } 301 302 void TsdGenerateNonTr(const int numHybridBands, const TSD_DATA *pTsdData, 303 const int ts, FIXP_DBL *pVdirectReal, 304 FIXP_DBL *pVdirectImag, FIXP_DBL *pVnonTrReal, 305 FIXP_DBL *pVnonTrImag, FIXP_DBL **ppDecorrInReal, 306 FIXP_DBL **ppDecorrInImag) { 307 int k = 0; 308 309 if (!isTrSlot(pTsdData, ts)) { 310 /* Let allpass based decorrelator read from direct input. */ 311 *ppDecorrInReal = pVdirectReal; 312 *ppDecorrInImag = pVdirectImag; 313 return; 314 } 315 316 /* Generate nonTr input signal for allpass based decorrelator */ 317 for (; k < TSD_START_BAND; k++) { 318 pVnonTrReal[k] = pVdirectReal[k]; 319 pVnonTrImag[k] = pVdirectImag[k]; 320 } 321 for (; k < numHybridBands; k++) { 322 pVnonTrReal[k] = (FIXP_DBL)0; 323 pVnonTrImag[k] = (FIXP_DBL)0; 324 } 325 *ppDecorrInReal = pVnonTrReal; 326 *ppDecorrInImag = pVnonTrImag; 327 } 328 329 void TsdApply(const int numHybridBands, const TSD_DATA *pTsdData, int *pTsdTs, 330 const FIXP_DBL *pVdirectReal, const FIXP_DBL *pVdirectImag, 331 FIXP_DBL *pDnonTrReal, FIXP_DBL *pDnonTrImag) { 332 const int ts = *pTsdTs; 333 334 if (isTrSlot(pTsdData, ts)) { 335 int k; 336 const FIXP_STP *phi = &phiTsd[pTsdData->bsTsdTrPhaseData[ts]]; 337 FDK_ASSERT((pTsdData->bsTsdTrPhaseData[ts] >= 0) && 338 (pTsdData->bsTsdTrPhaseData[ts] < 8)); 339 340 /* d = d_nonTr + v_direct * exp(j * bsTsdTrPhaseData[ts]/4 * pi ) */ 341 for (k = TSD_START_BAND; k < numHybridBands; k++) { 342 FIXP_DBL tempReal, tempImag; 343 cplxMult(&tempReal, &tempImag, pVdirectReal[k], pVdirectImag[k], *phi); 344 pDnonTrReal[k] += tempReal; 345 pDnonTrImag[k] += tempImag; 346 } 347 } 348 349 /* The modulo MAX_TSD_TIME_SLOTS operation is to avoid illegal memory accesses 350 * in case of errors. */ 351 *pTsdTs = (ts + 1) & (MAX_TSD_TIME_SLOTS - 1); 352 return; 353 } 354
