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 /*! 85 \file 86 \brief Envelope extraction prototypes 87 */ 88 89 #ifndef __ENVELOPE_EXTRACTION_H 90 #define __ENVELOPE_EXTRACTION_H 91 92 #include "sbrdecoder.h" 93 94 #include "FDK_bitstream.h" 95 #include "lpp_tran.h" 96 97 #include "psdec.h" 98 99 #define ENV_EXP_FRACT 0 100 /*!< Shift raw envelope data to support fractional numbers. 101 Can be set to 8 instead of 0 to enhance accuracy during concealment. 102 This is not required for conformance and #requantizeEnvelopeData() will 103 become more expensive. 104 */ 105 106 #define EXP_BITS 6 107 /*!< Size of exponent-part of a pseudo float envelope value (should be at least 6). 108 The remaining bits in each word are used for the mantissa (should be at least 10). 109 This format is used in the arrays iEnvelope[] and sbrNoiseFloorLevel[] 110 in the FRAME_DATA struct which must fit in a certain part of the output buffer 111 (See buffer management in sbr_dec.cpp). 112 Exponents and mantissas could also be stored in separate arrays. 113 Accessing the exponent or the mantissa would be simplified and the masks #MASK_E 114 resp. #MASK_M would no longer be required. 115 */ 116 117 #define MASK_M (((1 << (FRACT_BITS - EXP_BITS)) - 1) << EXP_BITS) /*!< Mask for extracting the mantissa of a pseudo float envelope value */ 118 #define MASK_E ((1 << EXP_BITS) - 1) /*!< Mask for extracting the exponent of a pseudo float envelope value */ 119 120 #define SIGN_EXT ( ((SCHAR)-1) ^ MASK_E) /*!< a CHAR-constant with all bits above our sign-bit set */ 121 #define ROUNDING ( (FIXP_SGL)(1<<(EXP_BITS-1)) ) /*!< 0.5-offset for rounding the mantissa of a pseudo-float envelope value */ 122 #define NRG_EXP_OFFSET 16 /*!< Will be added to the reference energy's exponent to prevent negative numbers */ 123 #define NOISE_EXP_OFFSET 38 /*!< Will be added to the noise level exponent to prevent negative numbers */ 124 125 typedef enum 126 { 127 HEADER_NOT_PRESENT, 128 HEADER_OK, 129 HEADER_RESET 130 } 131 SBR_HEADER_STATUS; 132 133 typedef enum 134 { 135 SBR_NOT_INITIALIZED, 136 UPSAMPLING, 137 SBR_HEADER, 138 SBR_ACTIVE 139 } 140 SBR_SYNC_STATE; 141 142 143 typedef enum 144 { 145 COUPLING_OFF = 0, 146 COUPLING_LEVEL, 147 COUPLING_BAL 148 } 149 COUPLING_MODE; 150 151 typedef struct 152 { 153 UCHAR nSfb[2]; /*!< Number of SBR-bands for low and high freq-resolution */ 154 UCHAR nNfb; /*!< Actual number of noise bands to read from the bitstream*/ 155 UCHAR numMaster; /*!< Number of SBR-bands in v_k_master */ 156 UCHAR lowSubband; /*!< QMF-band where SBR frequency range starts */ 157 UCHAR highSubband; /*!< QMF-band where SBR frequency range ends */ 158 UCHAR limiterBandTable[MAX_NUM_LIMITERS+1]; /*!< Limiter band table. */ 159 UCHAR noLimiterBands; /*!< Number of limiter bands. */ 160 UCHAR nInvfBands; /*!< Number of bands for inverse filtering */ 161 UCHAR *freqBandTable[2]; /*!< Pointers to freqBandTableLo and freqBandTableHi */ 162 UCHAR freqBandTableLo[MAX_FREQ_COEFFS/2+1]; 163 /*!< Mapping of SBR bands to QMF bands for low frequency resolution */ 164 UCHAR freqBandTableHi[MAX_FREQ_COEFFS+1]; 165 /*!< Mapping of SBR bands to QMF bands for high frequency resolution */ 166 UCHAR freqBandTableNoise[MAX_NOISE_COEFFS+1]; 167 /*!< Mapping of SBR noise bands to QMF bands */ 168 UCHAR v_k_master[MAX_FREQ_COEFFS+1]; 169 /*!< Master BandTable which freqBandTable is derived from */ 170 } 171 FREQ_BAND_DATA; 172 173 typedef FREQ_BAND_DATA *HANDLE_FREQ_BAND_DATA; 174 175 #define SBRDEC_ELD_GRID 1 176 #define SBRDEC_SYNTAX_SCAL 2 177 #define SBRDEC_SYNTAX_USAC 4 178 #define SBRDEC_SYNTAX_RSVD50 8 179 #define SBRDEC_LOW_POWER 16 /* Flag indicating that Low Power QMF mode shall be used. */ 180 #define SBRDEC_PS_DECODED 32 /* Flag indicating that PS was decoded and rendered. */ 181 #define SBRDEC_LD_MPS_QMF 512 /* Flag indicating that the LD-MPS QMF shall be used. */ 182 183 #define SBRDEC_HDR_STAT_RESET 1 184 #define SBRDEC_HDR_STAT_UPDATE 2 185 186 typedef struct { 187 UCHAR ampResolution; /*!< Amplitude resolution of envelope values (0: 1.5dB, 1: 3dB) */ 188 UCHAR xover_band; /*!< Start index in #v_k_master[] used for dynamic crossover frequency */ 189 UCHAR sbr_preprocessing; /*!< SBR prewhitening flag. */ 190 } SBR_HEADER_DATA_BS_INFO; 191 192 typedef struct { 193 /* Changes in these variables causes a reset of the decoder */ 194 UCHAR startFreq; /*!< Index for SBR start frequency */ 195 UCHAR stopFreq; /*!< Index for SBR highest frequency */ 196 UCHAR freqScale; /*!< 0: linear scale, 1-3 logarithmic scales */ 197 UCHAR alterScale; /*!< Flag for coarser frequency resolution */ 198 UCHAR noise_bands; /*!< Noise bands per octave, read from bitstream*/ 199 200 /* don't require reset */ 201 UCHAR limiterBands; /*!< Index for number of limiter bands per octave */ 202 UCHAR limiterGains; /*!< Index to select gain limit */ 203 UCHAR interpolFreq; /*!< Select gain calculation method (1: per QMF channel, 0: per SBR band) */ 204 UCHAR smoothingLength; /*!< Smoothing of gains over time (0: on 1: off) */ 205 206 } SBR_HEADER_DATA_BS; 207 208 typedef struct 209 { 210 SBR_SYNC_STATE syncState; /*!< The current initialization status of the header */ 211 212 UCHAR status; /*!< Flags field used for signaling a reset right before the processing starts and an update from config (e.g. ASC). */ 213 UCHAR frameErrorFlag; /*!< Frame data valid flag. CAUTION: This variable will be overwritten by the flag stored in the element structure. 214 This is necessary because of the frame delay. There it might happen that different slots use the same header. */ 215 UCHAR numberTimeSlots; /*!< AAC: 16,15 */ 216 UCHAR numberOfAnalysisBands; /*!< Number of QMF analysis bands */ 217 UCHAR timeStep; /*!< Time resolution of SBR in QMF-slots */ 218 UINT sbrProcSmplRate; /*!< SBR processing sampling frequency (!= OutputSamplingRate) 219 (always: CoreSamplingRate * UpSamplingFactor; even in single rate mode) */ 220 221 SBR_HEADER_DATA_BS bs_data; /*!< current SBR header. */ 222 SBR_HEADER_DATA_BS_INFO bs_info; /*!< SBR info. */ 223 224 FREQ_BAND_DATA freqBandData; /*!< Pointer to struct #FREQ_BAND_DATA */ 225 } 226 SBR_HEADER_DATA; 227 228 typedef SBR_HEADER_DATA *HANDLE_SBR_HEADER_DATA; 229 230 231 typedef struct 232 { 233 UCHAR frameClass; /*!< Select grid type */ 234 UCHAR nEnvelopes; /*!< Number of envelopes */ 235 UCHAR borders[MAX_ENVELOPES+1]; /*!< Envelope borders (in SBR-timeslots, e.g. mp3PRO: 0..11) */ 236 UCHAR freqRes[MAX_ENVELOPES]; /*!< Frequency resolution for each envelope (0=low, 1=high) */ 237 SCHAR tranEnv; /*!< Transient envelope, -1 if none */ 238 UCHAR nNoiseEnvelopes; /*!< Number of noise envelopes */ 239 UCHAR bordersNoise[MAX_NOISE_ENVELOPES+1];/*!< borders of noise envelopes */ 240 } 241 FRAME_INFO; 242 243 244 typedef struct 245 { 246 FIXP_SGL sfb_nrg_prev[MAX_FREQ_COEFFS]; /*!< Previous envelope (required for differential-coded values) */ 247 FIXP_SGL prevNoiseLevel[MAX_NOISE_COEFFS]; /*!< Previous noise envelope (required for differential-coded values) */ 248 COUPLING_MODE coupling; /*!< Stereo-mode of previous frame */ 249 INVF_MODE sbr_invf_mode[MAX_INVF_BANDS]; /*!< Previous strength of filtering in transposer */ 250 UCHAR ampRes; /*!< Previous amplitude resolution (0: 1.5dB, 1: 3dB) */ 251 UCHAR stopPos; /*!< Position in time where last envelope ended */ 252 UCHAR frameErrorFlag; /*!< Previous frame status */ 253 } 254 SBR_PREV_FRAME_DATA; 255 256 typedef SBR_PREV_FRAME_DATA *HANDLE_SBR_PREV_FRAME_DATA; 257 258 259 typedef struct 260 { 261 int nScaleFactors; /*!< total number of scalefactors in frame */ 262 263 FRAME_INFO frameInfo; /*!< time grid for current frame */ 264 UCHAR domain_vec[MAX_ENVELOPES]; /*!< Bitfield containing direction of delta-coding for each envelope (0:frequency, 1:time) */ 265 UCHAR domain_vec_noise[MAX_NOISE_ENVELOPES]; /*!< Same as above, but for noise envelopes */ 266 267 INVF_MODE sbr_invf_mode[MAX_INVF_BANDS]; /*!< Strength of filtering in transposer */ 268 COUPLING_MODE coupling; /*!< Stereo-mode */ 269 int ampResolutionCurrentFrame; /*!< Amplitude resolution of envelope values (0: 1.5dB, 1: 3dB) */ 270 271 UCHAR addHarmonics[MAX_FREQ_COEFFS]; /*!< Flags for synthetic sine addition */ 272 273 FIXP_SGL iEnvelope[MAX_NUM_ENVELOPE_VALUES]; /*!< Envelope data */ 274 FIXP_SGL sbrNoiseFloorLevel[MAX_NUM_NOISE_VALUES]; /*!< Noise envelope data */ 275 } 276 SBR_FRAME_DATA; 277 278 typedef SBR_FRAME_DATA *HANDLE_SBR_FRAME_DATA; 279 280 void initSbrPrevFrameData (HANDLE_SBR_PREV_FRAME_DATA h_prev_data, 281 int timeSlots); 282 283 284 int sbrGetSingleChannelElement (HANDLE_SBR_HEADER_DATA hHeaderData, 285 HANDLE_SBR_FRAME_DATA hFrameData, 286 HANDLE_FDK_BITSTREAM hBitBuf, 287 HANDLE_PS_DEC hParametricStereoDec, 288 const UINT flags, 289 const int overlap 290 ); 291 292 int sbrGetChannelPairElement (HANDLE_SBR_HEADER_DATA hHeaderData, 293 HANDLE_SBR_FRAME_DATA hFrameDataLeft, 294 HANDLE_SBR_FRAME_DATA hFrameDataRight, 295 HANDLE_FDK_BITSTREAM hBitBuf, 296 const UINT flags, 297 const int overlap); 298 299 SBR_HEADER_STATUS 300 sbrGetHeaderData (HANDLE_SBR_HEADER_DATA headerData, 301 HANDLE_FDK_BITSTREAM hBitBuf, 302 const UINT flags, 303 const int fIsSbrData); 304 305 /*! 306 \brief Initialize SBR header data 307 308 Copy default values to the header data struct and patch some entries 309 depending on the core codec. 310 */ 311 SBR_ERROR 312 initHeaderData ( 313 HANDLE_SBR_HEADER_DATA hHeaderData, 314 const int sampleRateIn, 315 const int sampleRateOut, 316 const int samplesPerFrame, 317 const UINT flags 318 ); 319 #endif 320
