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): Josef Hoepfl 98 99 Description: joint stereo processing 100 101 *******************************************************************************/ 102 103 #ifndef STEREO_H 104 #define STEREO_H 105 106 #include "machine_type.h" 107 #include "FDK_bitstream.h" 108 #include "common_fix.h" 109 110 #define SFB_PER_PRED_BAND 2 111 112 #define SR_FNA_OUT \ 113 0 /* Additional scaling of the CJointStereo_filterAndAdd()-output to avoid \ 114 overflows. */ 115 /* The scaling factor can be set to 0 if the coefficients are prescaled 116 * appropriately. */ 117 /* Prescaling via factor SF_FNA_COEFFS is done at compile-time but should only 118 * be */ 119 /* utilized if the coefficients are stored as FIXP_DBL. (cp. aac_rom.cpp/.h) */ 120 121 /* The NO_CPLX_PRED_BUGFIX-switch was introduced to enable decoding of 122 conformance-streams in way that they are comparable to buggy 123 reference-streams. This is established by storing the prediction direction 124 for computation of the "downmix MDCT of previous frame". This is not standard 125 compliant. Once correct reference-streams for complex-stereo-prediction are 126 available this switch becomes obsolete. 127 */ 128 /*#define NO_CPLX_PRED_BUGFIX*/ 129 130 enum { JointStereoMaximumGroups = 8, JointStereoMaximumBands = 64 }; 131 132 typedef struct { 133 UCHAR pred_dir; // 0 = prediction from mid to side channel, 1 = vice versa 134 UCHAR 135 igf_pred_dir; // 0 = prediction from mid to side channel, 1 = vice versa 136 UCHAR complex_coef; // 0 = alpha_q_im[x] is 0 for all prediction bands, 1 = 137 // alpha_q_im[x] is transmitted via bitstream 138 UCHAR use_prev_frame; // 0 = use current frame for MDST estimation, 1 = use 139 // current and previous frame 140 141 SHORT alpha_q_re[JointStereoMaximumGroups][JointStereoMaximumBands]; 142 SHORT alpha_q_im[JointStereoMaximumGroups][JointStereoMaximumBands]; 143 } CCplxPredictionData; 144 145 /* joint stereo scratch memory (valid for this frame) */ 146 typedef struct { 147 UCHAR MsMaskPresent; 148 UCHAR MsUsed[JointStereoMaximumBands]; /*!< every arry element contains flags 149 for up to 8 groups. this array is 150 also utilized for complex stereo 151 prediction. */ 152 UCHAR IGF_MsMaskPresent; 153 154 UCHAR cplx_pred_flag; /* stereo complex prediction was signalled for this 155 frame */ 156 UCHAR igf_cplx_pred_flag; 157 158 /* The following array and variable are needed for the case when INF is 159 * active */ 160 FIXP_DBL store_dmx_re_prev[1024]; 161 SHORT store_dmx_re_prev_e; 162 163 } CJointStereoData; 164 165 /* joint stereo persistent memory */ 166 typedef struct { 167 UCHAR clearSpectralCoeffs; /* indicates that the spectral coeffs must be 168 cleared because the transform splitting active 169 flag of the left and right channel was different 170 */ 171 172 FIXP_DBL *scratchBuffer; /* pointer to scratch buffer */ 173 174 FIXP_DBL 175 *spectralCoeffs[2]; /* spectral coefficients of this channel utilized by 176 complex stereo prediction */ 177 SHORT *specScale[2]; 178 179 SHORT alpha_q_re_prev[JointStereoMaximumGroups][JointStereoMaximumBands]; 180 SHORT alpha_q_im_prev[JointStereoMaximumGroups][JointStereoMaximumBands]; 181 182 UCHAR winSeqPrev; 183 UCHAR winShapePrev; 184 UCHAR winGroupsPrev; 185 186 } CJointStereoPersistentData; 187 188 /*! 189 \brief Read joint stereo data from bitstream 190 191 The function reads joint stereo data from bitstream. 192 193 \param bs bit stream handle data source. 194 \param pJointStereoData pointer to stereo data structure to receive decoded 195 data. \param windowGroups number of window groups. \param 196 scaleFactorBandsTransmitted number of transmitted scalefactor bands. \param 197 flags decoder flags 198 199 \return 0 on success, -1 on error. 200 */ 201 int CJointStereo_Read(HANDLE_FDK_BITSTREAM bs, 202 CJointStereoData *pJointStereoData, 203 const int windowGroups, 204 const int scaleFactorBandsTransmitted, 205 const int max_sfb_ste_clear, 206 CJointStereoPersistentData *pJointStereoPersistentData, 207 CCplxPredictionData *cplxPredictionData, 208 int cplxPredictionActiv, int scaleFactorBandsTotal, 209 int windowSequence, const UINT flags); 210 211 #endif /* #ifndef STEREO_H */ 212