1 2/* ----------------------------------------------------------------------------------------------------------- 3Software 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 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: long/short-block decoding 88 89******************************************************************************/ 90 91#ifndef BLOCK_H 92#define BLOCK_H 93 94#include "common_fix.h" 95 96#include "channelinfo.h" 97#include "FDK_bitstream.h" 98 99/* PNS (of block) */ 100void CPns_Read (CPnsData *pPnsData, 101 HANDLE_FDK_BITSTREAM bs, 102 const CodeBookDescription *hcb, 103 SHORT *pScaleFactor, 104 UCHAR global_gain, 105 int band, 106 int group); 107 108 109void CPns_Apply (const CPnsData *pPnsData, 110 const CIcsInfo *pIcsInfo, 111 SPECTRAL_PTR pSpectrum, 112 const SHORT *pSpecScale, 113 const SHORT *pScaleFactor, 114 const SamplingRateInfo *pSamplingRateInfo, 115 const INT granuleLength, 116 const int channel); 117 118 119 120/* TNS (of block) */ 121/*! 122 \brief Read tns data-present flag from bitstream 123 124 The function reads the data-present flag for tns from 125 the bitstream. 126 127 \return none 128*/ 129void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs, 130 CTnsData *pTnsData); 131 132void CTns_ReadDataPresentUsac( 133 HANDLE_FDK_BITSTREAM hBs, 134 CTnsData *pTnsData0, 135 CTnsData *pTnsData1, 136 const CIcsInfo *pIcsInfo, 137 const UINT flags, 138 const int fCommonWindow 139 ); 140 141AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs, 142 CTnsData *pTnsData, 143 const CIcsInfo *pIcsInfo, 144 const UINT flags); 145 146void CTns_Apply ( CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */ 147 const CIcsInfo *pIcsInfo, 148 SPECTRAL_PTR pSpectralCoefficient, 149 const SamplingRateInfo *pSamplingRateInfo, 150 const INT granuleLength); 151 152/* Block */ 153 154LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, const LONG q); 155 156/** 157 * \brief Read scale factor data. See chapter 4.6.2.3.2 of ISO/IEC 14496-3. 158 * The SF_OFFSET = 100 value referenced in chapter 4.6.2.3.3 is already substracted 159 * from the scale factor values. Also includes PNS data reading. 160 * \param bs bit stream handle data source 161 * \param pAacDecoderChannelInfo channel context info were decoded data is stored into. 162 * \param flags the decoder flags. 163 */ 164AAC_DECODER_ERROR CBlock_ReadScaleFactorData( 165 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 166 HANDLE_FDK_BITSTREAM bs, 167 const UINT flags 168 ); 169 170/** 171 * \brief Read Huffman encoded spectral data. 172 * \param pAacDecoderChannelInfo channel context info. 173 * \param pSamplingRateInfo sampling rate info (sfb offsets). 174 * \param flags syntax flags. 175 */ 176AAC_DECODER_ERROR CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs, 177 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 178 const SamplingRateInfo *pSamplingRateInfo, 179 const UINT flags); 180 181 182AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs, 183 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 184 const SamplingRateInfo *pSamplingRateInfo, 185 const UINT flags); 186 187/** 188 * \brief find a common exponent (shift factor) for all sfb in each Spectral window, and store them into 189 * CAacDecoderChannelInfo::specScale. 190 * \param pAacDecoderChannelInfo channel context info. 191 * \param pSamplingRateInfo sampling rate info (sfb offsets). 192 */ 193void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo); 194 195/** 196 * \brief Apply TNS and PNS tools. 197 */ 198void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[], 199 const SamplingRateInfo *pSamplingRateInfo, 200 const UINT flags, 201 const int channel ); 202 203/** 204 * \brief Transform MDCT spectral data into time domain 205 */ 206void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo, 207 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 208 INT_PCM outSamples[], 209 const SHORT frameLen, 210 const int stride, 211 const int frameOk, 212 FIXP_DBL *pWorkBuffer1); 213 214/** 215 * \brief Transform double lapped MDCT (AAC-ELD) spectral data into time domain. 216 */ 217void CBlock_FrequencyToTimeLowDelay(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo, 218 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 219 INT_PCM outSamples[], 220 const short frameLen, 221 const char stride); 222 223AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo); 224 225/** 226 * \brief Calculate 2^(lsb/4) * value^(4/3) 227 * \param pValue pointer to quantized value. The inverse quantized result is stored back here. 228 * \param lsb 2 LSBs of the scale factor (scaleFactor % 4) applied as power 2 factor to the 229 * resulting inverse quantized value. 230 * \return the exponent of the result (mantissa) stored into *pValue. 231 */ 232FDK_INLINE 233int EvaluatePower43 ( FIXP_DBL *pValue, 234 UINT lsb ) 235{ 236 FIXP_DBL value; 237 UINT freeBits; 238 UINT exponent; 239 240 value = *pValue; 241 freeBits = fNormz (value) ; 242 exponent = DFRACT_BITS - freeBits ; 243 FDK_ASSERT (exponent < 14); 244 245 UINT x = (((int)value << freeBits) >> 19) ; 246 UINT tableIndex = (x & 0x0FFF) >> 4 ; 247 FIXP_DBL invQVal ; 248 249 x = x & 0x0F; 250 251 UINT r0=(LONG)InverseQuantTable [tableIndex+0]; 252 UINT r1=(LONG)InverseQuantTable [tableIndex+1]; 253 USHORT nx=16-x; 254 UINT temp=(r0)*nx+(r1)*x; 255 invQVal = (FIXP_DBL)temp; 256 257 FDK_ASSERT(lsb < 4); 258 *pValue = fMultDiv2 (invQVal, MantissaTable [lsb][exponent]) ; 259 260 /* + 1 compensates fMultDiv2(). */ 261 return ExponentTable [lsb][exponent] + 1; 262} 263 264/** 265 * \brief determine the required shift scale for the given quantized value and scale (factor % 4) value. 266 */ 267FDK_INLINE int GetScaleFromValue (FIXP_DBL value, unsigned int lsb) 268{ 269 if (value!=(FIXP_DBL)0) 270 { 271 int scale = EvaluatePower43 (&value, lsb) ; 272 return CntLeadingZeros (value) - scale - 2 ; 273 } 274 else 275 return 0; /* Return zero, because its useless to scale a zero value, saves workload and avoids scaling overshifts. */ 276} 277 278 279//#ifdef AACDEC_HUFFMANDECODER_ENABLE 280 281/*! 282 \brief Read huffman codeword 283 284 The function reads the huffman codeword from the bitstream and 285 returns the index value. 286 287 \return index value 288*/ 289inline int CBlock_DecodeHuffmanWord( HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */ 290 const CodeBookDescription *hcb ) /*!< pointer to codebook description */ 291{ 292 UINT val; 293 UINT index = 0; 294 const USHORT (*CodeBook) [HuffmanEntries] = hcb->CodeBook; 295 296 while (1) 297 { 298 val = CodeBook[index][FDKreadBits(bs,HuffmanBits)]; /* Expensive memory access */ 299 300 if ((val & 1) == 0) 301 { 302 index = val>>2; 303 continue; 304 } 305 else 306 { 307 if (val & 2) 308 { 309 FDKpushBackCache(bs,1); 310 } 311 312 val >>= 2; 313 break; 314 } 315 } 316 317 return val; 318} 319 320//#endif /* AACDEC_HUFFMANDECODER_ENABLE */ 321 322#endif /* #ifndef BLOCK_H */ 323