1 /* ----------------------------------------------------------------------------- 2 Software License for The Fraunhofer FDK AAC Codec Library for Android 3 4 © Copyright 1995 - 2019 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 /******************* Library for basic calculation routines ******************** 96 97 Author(s): Manuel Jander, Josef Hoepfl, Youliy Ninov, Daniel Hagel 98 99 Description: MDCT/MDST routines 100 101 *******************************************************************************/ 102 103 #ifndef MDCT_H 104 #define MDCT_H 105 106 #include "common_fix.h" 107 108 #define MDCT_OUT_HEADROOM 2 /* Output additional headroom */ 109 110 #define PCM_OUT_BITS DFRACT_BITS 111 #define PCM_OUT_HEADROOM 8 /* Must have the same values as DMXH_HEADROOM */ 112 113 #define MDCT_OUTPUT_SCALE (-MDCT_OUT_HEADROOM + (DFRACT_BITS - PCM_OUT_BITS)) 114 /* Refer to "Output word length" in ISO/IEC 14496-3:2008(E) 23.2.3.6 */ 115 #define MDCT_OUTPUT_GAIN 16 116 117 #define IMDCT_SCALE(x, s) \ 118 SATURATE_RIGHT_SHIFT((x), ((s) + MDCT_OUTPUT_SCALE), PCM_OUT_BITS) 119 #define IMDCT_SCALE_DBL(x) (FIXP_DBL)(x) 120 #define IMDCT_SCALE_DBL_LSH1(x) SATURATE_LEFT_SHIFT_ALT((x), 1, DFRACT_BITS) 121 122 #define MLT_FLAG_CURR_ALIAS_SYMMETRY 1 123 124 typedef enum { 125 BLOCK_LONG = 0, /* normal long block */ 126 BLOCK_START, /* long start block */ 127 BLOCK_SHORT, /* 8 short blocks sequence */ 128 BLOCK_STOP /* long stop block*/ 129 } BLOCK_TYPE; 130 131 typedef enum { SHAPE_SINE = 0, SHAPE_KBD, SHAPE_LOL } WINDOW_SHAPE; 132 133 /** 134 * \brief MDCT persistent data 135 */ 136 typedef struct { 137 union { 138 FIXP_DBL *freq; 139 FIXP_DBL *time; 140 } overlap; /**< Pointer to overlap memory */ 141 142 const FIXP_WTP *prev_wrs; /**< pointer to previous right window slope */ 143 int prev_tl; /**< previous transform length */ 144 int prev_nr; /**< previous right window offset */ 145 int prev_fr; /**< previous right window slope length */ 146 int ov_offset; /**< overlap time data fill level */ 147 int ov_size; /**< Overlap buffer size in words */ 148 149 int prevAliasSymmetry; 150 int prevPrevAliasSymmetry; 151 152 FIXP_DBL *pFacZir; 153 FIXP_DBL *pAsymOvlp; /**< pointer to asymmetric overlap (used for stereo LPD 154 transition) */ 155 } mdct_t; 156 157 typedef mdct_t *H_MDCT; 158 159 /** 160 * \brief Initialize as valid MDCT handle 161 * 162 * \param hMdct handle of an allocated MDCT handle. 163 * \param overlap pointer to FIXP_DBL overlap buffer. 164 * \param overlapBufferSize size in FIXP_DBLs of the given overlap buffer. 165 */ 166 void mdct_init(H_MDCT hMdct, FIXP_DBL *overlap, INT overlapBufferSize); 167 168 /** 169 * \brief perform MDCT transform (time domain to frequency domain) with given 170 * parameters. 171 * 172 * \param hMdct handle of an allocated MDCT handle. 173 * \param pTimeData pointer to input time domain signal 174 * \param noInSamples number of input samples 175 * \param mdctData pointer to where the resulting MDCT spectrum will be stored 176 * into. 177 * \param nSpec number of spectra 178 * \param pMdctData_e pointer to the input data exponent. Updated accordingly on 179 * return for output data. 180 * \return number of input samples processed. 181 */ 182 INT mdct_block(H_MDCT hMdct, const INT_PCM *pTimeData, const INT noInSamples, 183 FIXP_DBL *RESTRICT mdctData, const INT nSpec, const INT tl, 184 const FIXP_WTP *pRightWindowPart, const INT fr, 185 SHORT *pMdctData_e); 186 187 /** 188 * \brief add/multiply 2/N transform gain and MPEG4 part 3 defined output gain 189 * (see definition of MDCT_OUTPUT_GAIN) to given mantissa factor and exponent. 190 * \param pGain pointer to the mantissa of a gain factor to be applied to IMDCT 191 * data. 192 * \param pExponent pointer to the exponent of a gain factor to be applied to 193 * IMDCT data. 194 * \param tl length of the IMDCT where the gain *pGain * (2 ^ *pExponent) will 195 * be applied to. 196 */ 197 void imdct_gain(FIXP_DBL *pGain, int *pExponent, int tl); 198 199 /** 200 * \brief drain buffered output samples into given buffer. Changes the MDCT 201 * state. 202 */ 203 INT imdct_drain(H_MDCT hMdct, FIXP_DBL *pTimeData, INT nrSamplesRoom); 204 205 /** 206 * \brief Copy overlap time domain data to given buffer. Does not change the 207 * MDCT state. 208 * \return number of actually copied samples (ov + nr). 209 */ 210 INT imdct_copy_ov_and_nr(H_MDCT hMdct, FIXP_DBL *pTimeData, INT nrSamples); 211 212 /** 213 * \brief Adapt MDCT parameters for non-matching window slopes. 214 * \param hMdct handle of an allocated MDCT handle. 215 * \param pfl pointer to left overlap window side length. 216 * \param pnl pointer to length of the left n part of the window. 217 * \param tl transform length. 218 * \param wls pointer to the left side overlap window coefficients. 219 * \param noOutSamples desired number of output samples. 220 */ 221 void imdct_adapt_parameters(H_MDCT hMdct, int *pfl, int *pnl, int tl, 222 const FIXP_WTP *wls, int noOutSamples); 223 224 /** 225 * \brief perform several inverse MLT transforms (frequency domain to time 226 * domain) with given parameters. 227 * 228 * \param hMdct handle of an allocated MDCT handle. 229 * \param output pointer to where the output time domain signal will be stored 230 * into. 231 * \param spectrum pointer to the input MDCT spectra. 232 * \param scalefactors exponents of the input spectrum. 233 * \param nSpec number of MDCT spectrums. 234 * \param noOutSamples desired number of output samples. 235 * \param tl transform length. 236 * \param wls pointer to the left side overlap window coefficients. 237 * \param fl left overlap window side length. 238 * \param wrs pointer to the right side overlap window coefficients of all 239 * individual IMDCTs. 240 * \param fr right overlap window side length of all individual IMDCTs. 241 * \param gain factor to apply to output samples (if != 0). 242 * \param flags flags controlling the type of transform 243 * \return number of output samples returned. 244 */ 245 INT imlt_block(H_MDCT hMdct, FIXP_DBL *output, FIXP_DBL *spectrum, 246 const SHORT scalefactor[], const INT nSpec, 247 const INT noOutSamples, const INT tl, const FIXP_WTP *wls, 248 INT fl, const FIXP_WTP *wrs, const INT fr, FIXP_DBL gain, 249 int flags); 250 251 #endif /* MDCT_H */ 252