1 /* ----------------------------------------------------------------------------- 2 Software License for The Fraunhofer FDK AAC Codec Library for Android 3 4 © Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung 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@iis.fraunhofer.de 93 ----------------------------------------------------------------------------- */ 94 95 /**************************** AAC decoder library ****************************** 96 97 Author(s): Matthias Hildenbrand 98 99 Description: USAC ACELP frame decoder 100 101 *******************************************************************************/ 102 103 #ifndef USACDEC_ACELP_H 104 #define USACDEC_ACELP_H 105 106 #include "common_fix.h" 107 #include "FDK_bitstream.h" 108 #include "usacdec_const.h" 109 #include "usacdec_rom.h" 110 111 //#define ENHANCED_TCX_TD_CONCEAL_ENABLE 112 113 /** Structure which holds the ACELP internal persistent memory */ 114 typedef struct { 115 FIXP_DBL old_exc_mem[PIT_MAX_MAX + L_INTERPOL]; 116 FIXP_DBL old_syn_mem[M_LP_FILTER_ORDER]; /* synthesis filter states */ 117 FIXP_SGL A[M_LP_FILTER_ORDER]; 118 INT A_exp; 119 FIXP_DBL gc_threshold; 120 FIXP_DBL de_emph_mem; 121 FIXP_SGL past_gpit; 122 FIXP_DBL past_gcode; 123 USHORT old_T0; 124 UCHAR old_T0_frac; 125 FIXP_DBL deemph_mem_wsyn; 126 FIXP_DBL wsyn_rms; 127 SHORT seed_ace; 128 } CAcelpStaticMem; 129 130 /** Structure which holds the parameter data needed to decode one ACELP frame. 131 */ 132 typedef struct { 133 UCHAR 134 acelp_core_mode; /**< mean excitation energy index for whole ACELP frame 135 */ 136 UCHAR mean_energy; /**< acelp core mode for whole ACELP frame */ 137 USHORT T0[NB_SUBFR]; 138 UCHAR T0_frac[NB_SUBFR]; 139 UCHAR ltp_filtering_flag[NB_SUBFR]; /**< controlls whether LTP postfilter is 140 active for each ACELP subframe */ 141 SHORT icb_index[NB_SUBFR] 142 [8]; /**< innovative codebook index for each ACELP subframe */ 143 UCHAR gains[NB_SUBFR]; /**< gain index for each ACELP subframe */ 144 } CAcelpChannelData; 145 146 /** 147 * \brief Read the acelp_coding() bitstream part. 148 * \param[in] hBs bitstream handle to read data from. 149 * \param[out] acelpData pointer to structure to store the parsed data of one 150 * ACELP frame. 151 * \param[in] acelp_core_mode the ACELP core mode index. 152 * \param[in] coreCoderFrameLength length of core coder frame (1024|768) 153 */ 154 INT CLpd_AcelpRead(HANDLE_FDK_BITSTREAM hBs, CAcelpChannelData *acelpData, 155 INT acelp_core_mode, INT i_offset, INT coreCoderFrameLength); 156 /** 157 * \brief Initialization of memory before one LPD frame is decoded 158 * \param[out] synth_buf synthesis buffer to be initialized, exponent = SF_SYNTH 159 * \param[in] old_synth past synthesis of previous LPD frame, exponent = 160 * SF_SYNTH 161 * \param[out] synth_buf_fb fullband synthesis buffer to be initialized, 162 * exponent = SF_SYNTH 163 * \param[in] old_synth_fb past fullband synthesis of previous LPD frame, 164 * exponent = SF_SYNTH 165 * \param[out] pitch vector where decoded pitch lag values are stored 166 * \param[in] old_T_pf past pitch lag values of previous LPD frame 167 * \param[in] samplingRate sampling rate for pitch lag offset calculation 168 * \param[out] i_offset pitch lag offset for the decoding of the pitch lag 169 * \param[in] coreCoderFrameLength length of core coder frame (1024|768) 170 */ 171 void Acelp_PreProcessing(FIXP_DBL *synth_buf, FIXP_DBL *old_synth, INT *pitch, 172 INT *old_T_pf, FIXP_DBL *pit_gain, 173 FIXP_DBL *old_gain_pf, INT samplingRate, INT *i_offset, 174 INT coreCoderFrameLength, INT synSfd, 175 INT nbSubfrSuperfr); 176 177 /** 178 * \brief Save tail of buffers for the initialization of the next LPD frame 179 * \param[in] synth_buf synthesis of current LPD frame, exponent = SF_SYNTH 180 * \param[out] old_synth memory where tail of fullband synth_buf is stored, 181 * exponent = SF_SYNTH 182 * \param[in] synth_buf_fb fullband synthesis of current LPD frame, exponent = 183 * SF_SYNTH 184 * \param[out] old_synth_fb memory where tail of fullband synth_buf is stored, 185 * exponent = SF_SYNTH 186 * \param[in] pitch decoded pitch lag values of current LPD frame 187 * \param[out] old_T_pf memory where last SYN_SFD pitch lag values are stored 188 */ 189 void Acelp_PostProcessing(FIXP_DBL *synth_buf, FIXP_DBL *old_synth, INT *pitch, 190 INT *old_T_pf, INT coreCoderFrameLength, INT synSfd, 191 INT nbSubfrSuperfr); 192 193 /** 194 * \brief Decode one ACELP frame (three or four ACELP subframes with 64 samples 195 * each) 196 * \param[in,out] acelp_mem pointer to ACELP memory structure 197 * \param[in] i_offset pitch lag offset 198 * \param[in] lsp_old LPC filter in LSP domain corresponding to previous frame 199 * \param[in] lsp_new LPC filter in LSP domain corresponding to current frame 200 * \param[in] stab_fac stability factor constrained by 0<=stab_fac<=1.0, 201 * exponent = SF_STAB 202 * \param[in] acelpData pointer to struct with data which is needed for decoding 203 * one ACELP frame 204 * \param[out] synth ACELP output signal 205 * \param[out] pT four decoded pitch lag values 206 * \param[in] coreCoderFrameLength length of core coder frame (1024|768) 207 */ 208 void CLpd_AcelpDecode(CAcelpStaticMem *acelp_mem, INT i_offset, 209 const FIXP_LPC lsp_old[M_LP_FILTER_ORDER], 210 const FIXP_LPC lsp_new[M_LP_FILTER_ORDER], 211 FIXP_SGL stab_fac, CAcelpChannelData *acelpData, 212 INT numLostSubframes, int lastLpcLost, int frameCnt, 213 FIXP_DBL synth[], int pT[], FIXP_DBL *pit_gain, 214 INT coreCoderFrameLength); 215 216 /** 217 * \brief Reset ACELP internal memory. 218 * \param[out] acelp_mem pointer to ACELP memory structure 219 */ 220 void CLpd_AcelpReset(CAcelpStaticMem *acelp_mem); 221 222 /** 223 * \brief Initialize ACELP internal memory in case of FAC before ACELP decoder 224 * is called 225 * \param[in] synth points to end+1 of past valid synthesis signal, exponent = 226 * SF_SYNTH 227 * \param[in] last_lpd_mode last lpd mode 228 * \param[in] last_last_lpd_mode lpd mode before last_lpd_mode 229 * \param[in] A_new LP synthesis filter coeffs corresponding to last frame, 230 * exponent = SF_A_COEFFS 231 * \param[in] A_old LP synthesis filter coeffs corresponding to the frame before 232 * last frame, exponent = SF_A_COEFFS 233 * \param[in,out] acelp_mem pointer to ACELP memory structure 234 * \param[in] coreCoderFrameLength length of core coder frame (1024|768) 235 */ 236 void CLpd_AcelpPrepareInternalMem(const FIXP_DBL *synth, UCHAR last_lpd_mode, 237 UCHAR last_last_lpd_mode, 238 const FIXP_LPC *A_new, const INT A_new_exp, 239 const FIXP_LPC *A_old, const INT A_old_exp, 240 CAcelpStaticMem *acelp_mem, 241 INT coreCoderFrameLength, INT clearOldExc, 242 UCHAR lpd_mode); 243 244 /** 245 * \brief Calculate zero input response (zir) of the acelp synthesis filter 246 * \param[in] A LP synthesis filter coefficients, exponent = SF_A_COEFFS 247 * \param[in,out] acelp_mem pointer to ACELP memory structure 248 * \param[in] length length of zir 249 * \param[out] zir pointer to zir output buffer, exponent = SF_SYNTH 250 */ 251 void CLpd_Acelp_Zir(const FIXP_LPC A[], const INT A_exp, 252 CAcelpStaticMem *acelp_mem, const INT length, 253 FIXP_DBL zir[], int doDeemph); 254 255 /** 256 * \brief Borrow static excitation memory from ACELP decoder 257 * \param[in] acelp_mem pointer to ACELP memory structure 258 * \param[in] length number of requested FIXP_DBL values 259 * \return pointer to requested memory 260 * 261 * The caller has to take care not to overwrite valid memory areas. 262 * During TCX/FAC calculations and before CLpd_AcelpPrepareInternalMem() is 263 * called, the following memory size is available: 264 * - 256 samples in case of ACELP -> TCX20 -> ACELP transition 265 * - PIT_MAX_MAX+L_INTERPOL samples in all other cases 266 */ 267 FIXP_DBL *CLpd_ACELP_GetFreeExcMem(CAcelpStaticMem *acelp_mem, INT length); 268 269 void CLpd_TcxTDConceal(CAcelpStaticMem *acelp_mem, SHORT *pitch, 270 const FIXP_LPC lsp_old[M_LP_FILTER_ORDER], 271 const FIXP_LPC lsp_new[M_LP_FILTER_ORDER], 272 const FIXP_SGL stab_fac, INT numLostSubframes, 273 FIXP_DBL synth[], INT coreCoderFrameLength, 274 UCHAR last_tcx_noise_factor); 275 276 inline SHORT E_UTIL_random(SHORT *seed) { 277 *seed = (SHORT)((((LONG)*seed * (LONG)31821) >> 1) + (LONG)13849); 278 return (*seed); 279 } 280 281 #endif /* USACDEC_ACELP_H */ 282