1 2 /* ----------------------------------------------------------------------------------------------------------- 3 Software License for The Fraunhofer FDK AAC Codec Library for Android 4 5 Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur Frderung 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 (at) iis.fraunhofer.de 82 ----------------------------------------------------------------------------------------------------------- */ 83 84 /******************************** MPEG Audio Encoder ************************** 85 86 Initial author: M.Werner 87 contents/description: Quantization 88 89 ******************************************************************************/ 90 91 #include "quantize.h" 92 93 #include "aacEnc_rom.h" 94 95 /***************************************************************************** 96 97 functionname: FDKaacEnc_quantizeLines 98 description: quantizes spectrum lines 99 returns: 100 input: global gain, number of lines to process, spectral data 101 output: quantized spectrum 102 103 *****************************************************************************/ 104 static void FDKaacEnc_quantizeLines(INT gain, 105 INT noOfLines, 106 FIXP_DBL *mdctSpectrum, 107 SHORT *quaSpectrum) 108 { 109 int line; 110 FIXP_DBL k = FL2FXCONST_DBL(-0.0946f + 0.5f)>>16; 111 FIXP_QTD quantizer = FDKaacEnc_quantTableQ[(-gain)&3]; 112 INT quantizershift = ((-gain)>>2)+1; 113 114 115 for (line = 0; line < noOfLines; line++) 116 { 117 FIXP_DBL accu = fMultDiv2(mdctSpectrum[line],quantizer); 118 119 if (accu < FL2FXCONST_DBL(0.0f)) 120 { 121 accu=-accu; 122 /* normalize */ 123 INT accuShift = CntLeadingZeros(accu) - 1; /* CountLeadingBits() is not necessary here since test value is always > 0 */ 124 accu <<= accuShift; 125 INT tabIndex = (INT)(accu>>(DFRACT_BITS-2-MANT_DIGITS))&(~MANT_SIZE); 126 INT totalShift = quantizershift-accuShift+1; 127 accu = fMultDiv2(FDKaacEnc_mTab_3_4[tabIndex],FDKaacEnc_quantTableE[totalShift&3]); 128 totalShift = (16-4)-(3*(totalShift>>2)); 129 FDK_ASSERT(totalShift >=0); /* MAX_QUANT_VIOLATION */ 130 accu >>= fixMin(totalShift,DFRACT_BITS-1); 131 quaSpectrum[line] = (SHORT)(-((LONG)(k + accu) >> (DFRACT_BITS-1-16))); 132 } 133 else if(accu > FL2FXCONST_DBL(0.0f)) 134 { 135 /* normalize */ 136 INT accuShift = CntLeadingZeros(accu) - 1; /* CountLeadingBits() is not necessary here since test value is always > 0 */ 137 accu <<= accuShift; 138 INT tabIndex = (INT)(accu>>(DFRACT_BITS-2-MANT_DIGITS))&(~MANT_SIZE); 139 INT totalShift = quantizershift-accuShift+1; 140 accu = fMultDiv2(FDKaacEnc_mTab_3_4[tabIndex],FDKaacEnc_quantTableE[totalShift&3]); 141 totalShift = (16-4)-(3*(totalShift>>2)); 142 FDK_ASSERT(totalShift >=0); /* MAX_QUANT_VIOLATION */ 143 accu >>= fixMin(totalShift,DFRACT_BITS-1); 144 quaSpectrum[line] = (SHORT)((LONG)(k + accu) >> (DFRACT_BITS-1-16)); 145 } 146 else 147 quaSpectrum[line]=0; 148 } 149 } 150 151 152 /***************************************************************************** 153 154 functionname:iFDKaacEnc_quantizeLines 155 description: iquantizes spectrum lines 156 mdctSpectrum = iquaSpectrum^4/3 *2^(0.25*gain) 157 input: global gain, number of lines to process,quantized spectrum 158 output: spectral data 159 160 *****************************************************************************/ 161 static void FDKaacEnc_invQuantizeLines(INT gain, 162 INT noOfLines, 163 SHORT *quantSpectrum, 164 FIXP_DBL *mdctSpectrum) 165 166 { 167 INT iquantizermod; 168 INT iquantizershift; 169 INT line; 170 171 iquantizermod = gain&3; 172 iquantizershift = gain>>2; 173 174 for (line = 0; line < noOfLines; line++) { 175 176 if(quantSpectrum[line] < 0) { 177 FIXP_DBL accu; 178 INT ex,specExp,tabIndex; 179 FIXP_DBL s,t; 180 181 accu = (FIXP_DBL) -quantSpectrum[line]; 182 183 ex = CountLeadingBits(accu); 184 accu <<= ex; 185 specExp = (DFRACT_BITS-1) - ex; 186 187 FDK_ASSERT(specExp < 14); /* this fails if abs(value) > 8191 */ 188 189 tabIndex = (INT)(accu>>(DFRACT_BITS-2-MANT_DIGITS))&(~MANT_SIZE); 190 191 /* calculate "mantissa" ^4/3 */ 192 s = FDKaacEnc_mTab_4_3Elc[tabIndex]; 193 194 /* get approperiate exponent multiplier for specExp^3/4 combined with scfMod */ 195 t = FDKaacEnc_specExpMantTableCombElc[iquantizermod][specExp]; 196 197 /* multiply "mantissa" ^4/3 with exponent multiplier */ 198 accu = fMult(s,t); 199 200 /* get approperiate exponent shifter */ 201 specExp = FDKaacEnc_specExpTableComb[iquantizermod][specExp]-1; /* -1 to avoid overflows in accu */ 202 203 if ((-iquantizershift-specExp) < 0) 204 accu <<= -(-iquantizershift-specExp); 205 else 206 accu >>= -iquantizershift-specExp; 207 208 mdctSpectrum[line] = -accu; 209 } 210 else if (quantSpectrum[line] > 0) { 211 FIXP_DBL accu; 212 INT ex,specExp,tabIndex; 213 FIXP_DBL s,t; 214 215 accu = (FIXP_DBL)(INT)quantSpectrum[line]; 216 217 ex = CountLeadingBits(accu); 218 accu <<= ex; 219 specExp = (DFRACT_BITS-1) - ex; 220 221 FDK_ASSERT(specExp < 14); /* this fails if abs(value) > 8191 */ 222 223 tabIndex = (INT)(accu>>(DFRACT_BITS-2-MANT_DIGITS))&(~MANT_SIZE); 224 225 /* calculate "mantissa" ^4/3 */ 226 s = FDKaacEnc_mTab_4_3Elc[tabIndex]; 227 228 /* get approperiate exponent multiplier for specExp^3/4 combined with scfMod */ 229 t = FDKaacEnc_specExpMantTableCombElc[iquantizermod][specExp]; 230 231 /* multiply "mantissa" ^4/3 with exponent multiplier */ 232 accu = fMult(s,t); 233 234 /* get approperiate exponent shifter */ 235 specExp = FDKaacEnc_specExpTableComb[iquantizermod][specExp]-1; /* -1 to avoid overflows in accu */ 236 237 if (( -iquantizershift-specExp) < 0) 238 accu <<= -(-iquantizershift-specExp); 239 else 240 accu >>= -iquantizershift-specExp; 241 242 mdctSpectrum[line] = accu; 243 } 244 else { 245 mdctSpectrum[line] = FL2FXCONST_DBL(0.0f); 246 } 247 } 248 } 249 250 /***************************************************************************** 251 252 functionname: FDKaacEnc_QuantizeSpectrum 253 description: quantizes the entire spectrum 254 returns: 255 input: number of scalefactor bands to be quantized, ... 256 output: quantized spectrum 257 258 *****************************************************************************/ 259 void FDKaacEnc_QuantizeSpectrum(INT sfbCnt, 260 INT maxSfbPerGroup, 261 INT sfbPerGroup, 262 INT *sfbOffset, 263 FIXP_DBL *mdctSpectrum, 264 INT globalGain, 265 INT *scalefactors, 266 SHORT *quantizedSpectrum) 267 { 268 INT sfbOffs,sfb; 269 270 /* in FDKaacEnc_quantizeLines quaSpectrum is calculated with: 271 spec^(3/4) * 2^(-3/16*QSS) * 2^(3/4*scale) + k 272 simplify scaling calculation and reduce QSS before: 273 spec^(3/4) * 2^(-3/16*(QSS - 4*scale)) */ 274 275 for(sfbOffs=0;sfbOffs<sfbCnt;sfbOffs+=sfbPerGroup) 276 for (sfb = 0; sfb < maxSfbPerGroup; sfb++) 277 { 278 INT scalefactor = scalefactors[sfbOffs+sfb] ; 279 280 FDKaacEnc_quantizeLines(globalGain - scalefactor, /* QSS */ 281 sfbOffset[sfbOffs+sfb+1] - sfbOffset[sfbOffs+sfb], 282 mdctSpectrum + sfbOffset[sfbOffs+sfb], 283 quantizedSpectrum + sfbOffset[sfbOffs+sfb]); 284 } 285 } 286 287 /***************************************************************************** 288 289 functionname: FDKaacEnc_calcSfbDist 290 description: calculates distortion of quantized values 291 returns: distortion 292 input: gain, number of lines to process, spectral data 293 output: 294 295 *****************************************************************************/ 296 FIXP_DBL FDKaacEnc_calcSfbDist(FIXP_DBL *mdctSpectrum, 297 SHORT *quantSpectrum, 298 INT noOfLines, 299 INT gain 300 ) 301 { 302 INT i,scale; 303 FIXP_DBL xfsf; 304 FIXP_DBL diff; 305 FIXP_DBL invQuantSpec; 306 307 xfsf = FL2FXCONST_DBL(0.0f); 308 309 for (i=0; i<noOfLines; i++) { 310 /* quantization */ 311 FDKaacEnc_quantizeLines(gain, 312 1, 313 &mdctSpectrum[i], 314 &quantSpectrum[i]); 315 316 if (fAbs(quantSpectrum[i])>MAX_QUANT) { 317 return FL2FXCONST_DBL(0.0f); 318 } 319 /* inverse quantization */ 320 FDKaacEnc_invQuantizeLines(gain,1,&quantSpectrum[i],&invQuantSpec); 321 322 /* dist */ 323 diff = fixp_abs(fixp_abs(invQuantSpec) - fixp_abs(mdctSpectrum[i]>>1)); 324 325 scale = CountLeadingBits(diff); 326 diff = scaleValue(diff, scale); 327 diff = fPow2(diff); 328 scale = fixMin(2*(scale-1), DFRACT_BITS-1); 329 330 diff = scaleValue(diff, -scale); 331 332 xfsf = xfsf + diff; 333 } 334 335 xfsf = CalcLdData(xfsf); 336 337 return xfsf; 338 } 339 340 /***************************************************************************** 341 342 functionname: FDKaacEnc_calcSfbQuantEnergyAndDist 343 description: calculates energy and distortion of quantized values 344 returns: 345 input: gain, number of lines to process, quantized spectral data, 346 spectral data 347 output: energy, distortion 348 349 *****************************************************************************/ 350 void FDKaacEnc_calcSfbQuantEnergyAndDist(FIXP_DBL *mdctSpectrum, 351 SHORT *quantSpectrum, 352 INT noOfLines, 353 INT gain, 354 FIXP_DBL *en, 355 FIXP_DBL *dist) 356 { 357 INT i,scale; 358 FIXP_DBL invQuantSpec; 359 FIXP_DBL diff; 360 361 FIXP_DBL energy = FL2FXCONST_DBL(0.0f); 362 FIXP_DBL distortion = FL2FXCONST_DBL(0.0f); 363 364 for (i=0; i<noOfLines; i++) { 365 366 if (fAbs(quantSpectrum[i])>MAX_QUANT) { 367 *en = FL2FXCONST_DBL(0.0f); 368 *dist = FL2FXCONST_DBL(0.0f); 369 return; 370 } 371 372 /* inverse quantization */ 373 FDKaacEnc_invQuantizeLines(gain,1,&quantSpectrum[i],&invQuantSpec); 374 375 /* energy */ 376 energy += fPow2(invQuantSpec); 377 378 /* dist */ 379 diff = fixp_abs(fixp_abs(invQuantSpec) - fixp_abs(mdctSpectrum[i]>>1)); 380 381 scale = CountLeadingBits(diff); 382 diff = scaleValue(diff, scale); 383 diff = fPow2(diff); 384 385 scale = fixMin(2*(scale-1), DFRACT_BITS-1); 386 387 diff = scaleValue(diff, -scale); 388 389 distortion += diff; 390 } 391 392 *en = CalcLdData(energy)+FL2FXCONST_DBL(0.03125f); 393 *dist = CalcLdData(distortion); 394 } 395 396
