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 /******************* Library for basic calculation routines ******************** 96 97 Author(s): 98 99 Description: Library functions to calculate standard DCTs. This will most 100 likely be replaced by hand-optimized functions for the specific 101 target processor. 102 103 *******************************************************************************/ 104 105 #ifndef DCT_H 106 #define DCT_H 107 108 #include "common_fix.h" 109 110 void dct_getTables(const FIXP_WTP **ptwiddle, const FIXP_STP **sin_twiddle, 111 int *sin_step, int length); 112 113 /** 114 * \brief Calculate DCT type II of given length. The DCT IV is 115 * calculated by a complex FFT, with some pre and post twiddeling. 116 * A factor of sqrt(2/(N-1)) is NOT applied. 117 * \param pDat pointer to input/output data (in place processing). 118 * \param size size of pDat. 119 * \param pDat_e pointer to an integer containing the exponent of the data 120 * referenced by pDat. The exponent is updated accordingly. 121 */ 122 void dct_II(FIXP_DBL *pDat, FIXP_DBL *tmp, int size, int *pDat_e); 123 124 /** 125 * \brief Calculate DCT type III of given length. The DCT IV is 126 * calculated by a complex FFT, with some pre and post twiddeling. 127 * Note that the factor 0.5 for the sum term x[0] is 1.0 instead of 0.5. 128 * A factor of sqrt(2/N) is NOT applied. 129 * \param pDat pointer to input/output data (in place processing). 130 * \param size size of pDat. 131 * \param pDat_e pointer to an integer containing the exponent of the data 132 * referenced by pDat. The exponent is updated accordingly. 133 */ 134 void dct_III(FIXP_DBL *pDat, FIXP_DBL *tmp, int size, int *pDat_e); 135 136 /** 137 * \brief Calculate DST type III of given length. The DST III is 138 * calculated by a DCT III of mirrored input and sign-flipping of odd 139 * output coefficients. 140 * Note that the factor 0.5 for the sum term x[N-1] is 1.0 instead of 141 * 0.5. A factor of sqrt(2/N) is NOT applied. 142 * \param pDat pointer to input/output data (in place processing). 143 * \param size size of pDat. 144 * \param pDat_e pointer to an integer containing the exponent of the data 145 * referenced by pDat. The exponent is updated accordingly. 146 */ 147 void dst_III(FIXP_DBL *pDat, FIXP_DBL *tmp, int size, int *pDat_e); 148 149 /** 150 * \brief Calculate DCT type IV of given length. The DCT IV is 151 * calculated by a complex FFT, with some pre and post twiddeling. 152 * A factor of sqrt(2/N) is NOT applied. 153 * \param pDat pointer to input/output data (in place processing). 154 * \param size size of pDat. 155 * \param pDat_e pointer to an integer containing the exponent of the data 156 * referenced by pDat. The exponent is updated accordingly. 157 */ 158 void dct_IV(FIXP_DBL *pDat, int size, int *pDat_e); 159 160 /** 161 * \brief Calculate DST type IV of given length. The DST IV is 162 * calculated by a complex FFT, with some pre and post twiddeling. 163 * A factor of sqrt(2/N) is NOT applied. 164 * \param pDat pointer to input/output data (in place processing). 165 * \param size size of pDat. 166 * \param pDat_e pointer to an integer containing the exponent of the data 167 * referenced by pDat. The exponent is updated accordingly. 168 */ 169 void dst_IV(FIXP_DBL *pDat, int size, int *pDat_e); 170 171 #endif 172