1 2/* ----------------------------------------------------------------------------------------------------------- 3Software License for The Fraunhofer FDK AAC Codec Library for Android 4 5� Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V. 6 All rights reserved. 7 8 1. INTRODUCTION 9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements 10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio. 11This FDK AAC Codec software is intended to be used on a wide variety of Android devices. 12 13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual 14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by 15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part 16of the MPEG specifications. 17 18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer) 19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners 20individually for the purpose of encoding or decoding bit streams in products that are compliant with 21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license 22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec 23software may already be covered under those patent licenses when it is used for those licensed purposes only. 24 25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality, 26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional 27applications information and documentation. 28 292. COPYRIGHT LICENSE 30 31Redistribution and use in source and binary forms, with or without modification, are permitted without 32payment of copyright license fees provided that you satisfy the following conditions: 33 34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or 35your modifications thereto in source code form. 36 37You must retain the complete text of this software license in the documentation and/or other materials 38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form. 39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your 40modifications thereto to recipients of copies in binary form. 41 42The name of Fraunhofer may not be used to endorse or promote products derived from this library without 43prior written permission. 44 45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec 46software or your modifications thereto. 47 48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software 49and 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." 52 533. NO PATENT LICENSE 54 55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, 56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with 57respect to this software. 58 59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized 60by appropriate patent licenses. 61 624. DISCLAIMER 63 64This 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 66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages, 68including but not limited to procurement of substitute goods or services; loss of use, data, or profits, 69or business interruption, however caused and on any theory of liability, whether in contract, strict 70liability, or tort (including negligence), arising in any way out of the use of this software, even if 71advised of the possibility of such damage. 72 735. CONTACT INFORMATION 74 75Fraunhofer Institute for Integrated Circuits IIS 76Attention: Audio and Multimedia Departments - FDK AAC LL 77Am Wolfsmantel 33 7891058 Erlangen, Germany 79 80www.iis.fraunhofer.de/amm 81amm-info@iis.fraunhofer.de 82----------------------------------------------------------------------------------------------------------- */ 83 84/***************************** MPEG-4 AAC Decoder ************************** 85 86 Author(s): Josef Hoepfl 87 Description: temporal noise shaping tool 88 89******************************************************************************/ 90 91#include "aacdec_tns.h" 92#include "aac_rom.h" 93#include "FDK_bitstream.h" 94#include "channelinfo.h" 95 96 97 98/*! 99 \brief Reset tns data 100 101 The function resets the tns data 102 103 \return none 104*/ 105void CTns_Reset(CTnsData *pTnsData) 106{ 107 /* Note: the following FDKmemclear should not be required. */ 108 FDKmemclear(pTnsData->Filter, TNS_MAX_WINDOWS*TNS_MAXIMUM_FILTERS*sizeof(CFilter)); 109 FDKmemclear(pTnsData->NumberOfFilters, TNS_MAX_WINDOWS*sizeof(UCHAR)); 110 pTnsData->DataPresent = 0; 111 pTnsData->Active = 0; 112} 113 114void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */ 115 CTnsData *pTnsData) /*!< pointer to aac decoder channel info */ 116{ 117 pTnsData->DataPresent = (UCHAR) FDKreadBits(bs,1); 118} 119 120/*! 121 \brief Read tns data from bitstream 122 123 The function reads the elements for tns from 124 the bitstream. 125 126 \return none 127*/ 128AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs, 129 CTnsData *pTnsData, 130 const CIcsInfo *pIcsInfo, 131 const UINT flags) 132{ 133 UCHAR n_filt,order; 134 UCHAR length,coef_res,coef_compress; 135 UCHAR window; 136 UCHAR wins_per_frame = GetWindowsPerFrame(pIcsInfo); 137 UCHAR isLongFlag = IsLongBlock(pIcsInfo); 138 AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK; 139 140 if (!pTnsData->DataPresent) { 141 return ErrorStatus; 142 } 143 144 for (window = 0; window < wins_per_frame; window++) 145 { 146 pTnsData->NumberOfFilters[window] = n_filt = (UCHAR) FDKreadBits(bs, isLongFlag ? 2 : 1); 147 148 if (pTnsData->NumberOfFilters[window] > TNS_MAXIMUM_FILTERS){ 149 pTnsData->NumberOfFilters[window] = n_filt = TNS_MAXIMUM_FILTERS; 150 } 151 152 if (n_filt) 153 { 154 int index; 155 UCHAR nextstopband; 156 157 coef_res = (UCHAR) FDKreadBits(bs,1); 158 159 nextstopband = GetScaleFactorBandsTotal(pIcsInfo); 160 161 for (index=0; index < n_filt; index++) 162 { 163 CFilter *filter = &pTnsData->Filter[window][index]; 164 165 length = (UCHAR)FDKreadBits(bs, isLongFlag ? 6 : 4); 166 167 if (length > nextstopband){ 168 length = nextstopband; 169 } 170 171 filter->StartBand = nextstopband - length; 172 filter->StopBand = nextstopband; 173 nextstopband = filter->StartBand; 174 175 { 176 filter->Order = order = (UCHAR) FDKreadBits(bs, isLongFlag ? 5 : 3); 177 } 178 179 if (filter->Order > TNS_MAXIMUM_ORDER){ 180 filter->Order = order = TNS_MAXIMUM_ORDER; 181 } 182 183 if (order) 184 { 185 UCHAR coef,s_mask; 186 UCHAR i; 187 SCHAR n_mask; 188 static const UCHAR sgn_mask[] = { 0x2, 0x4, 0x8 }; 189 static const SCHAR neg_mask[] = { ~0x3, ~0x7, ~0xF }; 190 191 filter->Direction = FDKreadBits(bs,1) ? -1 : 1; 192 193 coef_compress = (UCHAR) FDKreadBits(bs,1); 194 195 filter->Resolution = coef_res + 3; 196 197 s_mask = sgn_mask[coef_res + 1 - coef_compress]; 198 n_mask = neg_mask[coef_res + 1 - coef_compress]; 199 200 for (i=0; i < order; i++) 201 { 202 coef = (UCHAR) FDKreadBits(bs,filter->Resolution - coef_compress); 203 filter->Coeff[i] = (coef & s_mask) ? (coef | n_mask) : coef; 204 } 205 } 206 } 207 } 208 } 209 210 pTnsData->Active = 1; 211 212 return ErrorStatus; 213} 214 215 216static void CTns_Filter (FIXP_DBL *spec, int size, int inc, FIXP_TCC coeff [], int order) 217{ 218 // - Simple all-pole filter of order "order" defined by 219 // y(n) = x(n) - a(2)*y(n-1) - ... - a(order+1)*y(n-order) 220 // 221 // - The state variables of the filter are initialized to zero every time 222 // 223 // - The output data is written over the input data ("in-place operation") 224 // 225 // - An input vector of "size" samples is processed and the index increment 226 // to the next data sample is given by "inc" 227 228 int i,j,N; 229 FIXP_DBL *pSpec; 230 FIXP_DBL maxVal=FL2FXCONST_DBL(0.0); 231 INT s; 232 233 FDK_ASSERT(order <= TNS_MAXIMUM_ORDER); 234 C_ALLOC_SCRATCH_START(state, FIXP_DBL, TNS_MAXIMUM_ORDER); 235 FDKmemclear(state, order*sizeof(FIXP_DBL)); 236 237 for (i=0; i<size; i++) { 238 maxVal = fixMax(maxVal,fixp_abs(spec[i])); 239 } 240 241 if ( maxVal > FL2FXCONST_DBL(0.03125*0.70710678118) ) 242 s = fixMax(CntLeadingZeros(maxVal)-6,0); 243 else 244 s = fixMax(CntLeadingZeros(maxVal)-5,0); 245 246 s = fixMin(s,2); 247 s = s-1; 248 249 if (inc == -1) 250 pSpec = &spec[size - 1]; 251 else 252 pSpec = &spec[0]; 253 254 FIXP_TCC *pCoeff; 255 256#define FIRST_PART_FLTR \ 257 FIXP_DBL x, *pState = state; \ 258 pCoeff = coeff; \ 259 \ 260 if (s < 0) \ 261 x = (pSpec [0]>>1) + fMultDiv2 (*pCoeff++, pState [0]) ; \ 262 else \ 263 x = (pSpec [0]<<s) + fMultDiv2 (*pCoeff++, pState [0]) ; 264 265#define INNER_FLTR_INLINE \ 266 x = fMultAddDiv2 (x, *pCoeff, pState [1]); \ 267 pState [0] = pState [1] - (fMultDiv2 (*pCoeff++, x) <<2) ; \ 268 pState++; 269 270#define LAST_PART_FLTR \ 271 if (s < 0) \ 272 *pSpec = x << 1; \ 273 else \ 274 *pSpec = x >> s; \ 275 *pState =(-x) << 1; \ 276 pSpec += inc ; 277 278 279 if (order>8) 280 { 281 N = (order-1)&7; 282 283 for (i = size ; i != 0 ; i--) 284 { 285 FIRST_PART_FLTR 286 287 for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } 288 289 INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE 290 INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE 291 292 LAST_PART_FLTR 293 } 294 295 } else if (order>4) { 296 297 N = (order-1)&3; 298 299 for (i = size ; i != 0 ; i--) 300 { 301 FIRST_PART_FLTR 302 for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } 303 304 INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE 305 306 LAST_PART_FLTR 307 } 308 309 } else { 310 311 N = order-1; 312 313 for (i = size ; i != 0 ; i--) 314 { 315 FIRST_PART_FLTR 316 317 for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } 318 319 LAST_PART_FLTR 320 } 321 } 322 323 C_ALLOC_SCRATCH_END(state, FIXP_DBL, TNS_MAXIMUM_ORDER); 324} 325 326/*! 327 \brief Apply tns to spectral lines 328 329 The function applies the tns to the spectrum, 330 331 \return none 332*/ 333void CTns_Apply ( 334 CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */ 335 const CIcsInfo *pIcsInfo, 336 SPECTRAL_PTR pSpectralCoefficient, 337 const SamplingRateInfo *pSamplingRateInfo, 338 const INT granuleLength 339 ) 340{ 341 int window,index,start,stop,size; 342 343 344 if (pTnsData->Active) 345 { 346 C_AALLOC_SCRATCH_START(coeff, FIXP_TCC, TNS_MAXIMUM_ORDER); 347 348 for (window=0; window < GetWindowsPerFrame(pIcsInfo); window++) 349 { 350 FIXP_DBL *pSpectrum = SPEC(pSpectralCoefficient, window, granuleLength); 351 352 for (index=0; index < pTnsData->NumberOfFilters[window]; index++) 353 { 354 CFilter *RESTRICT filter = &pTnsData->Filter[window][index]; 355 356 if (filter->Order > 0) 357 { 358 FIXP_TCC *pCoeff; 359 int tns_max_bands; 360 361 pCoeff = &coeff[filter->Order-1]; 362 if (filter->Resolution == 3) 363 { 364 int i; 365 for (i=0; i < filter->Order; i++) 366 *pCoeff-- = FDKaacDec_tnsCoeff3[filter->Coeff[i]+4]; 367 } 368 else 369 { 370 int i; 371 for (i=0; i < filter->Order; i++) 372 *pCoeff-- = FDKaacDec_tnsCoeff4[filter->Coeff[i]+8]; 373 } 374 375 switch (granuleLength) { 376 case 480: 377 tns_max_bands = tns_max_bands_tbl_480[pSamplingRateInfo->samplingRateIndex]; 378 break; 379 case 512: 380 tns_max_bands = tns_max_bands_tbl_512[pSamplingRateInfo->samplingRateIndex]; 381 break; 382 default: 383 tns_max_bands = GetMaximumTnsBands(pIcsInfo, pSamplingRateInfo->samplingRateIndex); 384 break; 385 } 386 387 start = fixMin( fixMin(filter->StartBand, tns_max_bands), 388 GetScaleFactorBandsTransmitted(pIcsInfo) ); 389 390 start = GetScaleFactorBandOffsets(pIcsInfo, pSamplingRateInfo)[start]; 391 392 stop = fixMin( fixMin(filter->StopBand, tns_max_bands), 393 GetScaleFactorBandsTransmitted(pIcsInfo) ); 394 395 stop = GetScaleFactorBandOffsets(pIcsInfo, pSamplingRateInfo)[stop]; 396 397 size = stop - start; 398 399 if (size > 0) { 400 CTns_Filter(&pSpectrum[start], 401 size, 402 filter->Direction, 403 coeff, 404 filter->Order ); 405 } 406 } 407 } 408 } 409 C_AALLOC_SCRATCH_END(coeff, FIXP_TCC, TNS_MAXIMUM_ORDER); 410 } 411 412} 413