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: CRC calculation 100 101 *******************************************************************************/ 102 103 #ifndef FDK_CRC_H 104 #define FDK_CRC_H 105 106 #include "FDK_bitstream.h" 107 108 #define MAX_CRC_REGS \ 109 3 /*!< Maximal number of overlapping crc region in ADTS channel pair element \ 110 is two. Select three independent regions preventively. */ 111 112 /** 113 * This structure describes single crc region used for crc calculation. 114 */ 115 typedef struct { 116 UCHAR isActive; 117 INT maxBits; 118 INT bitBufCntBits; 119 INT validBits; 120 121 } CCrcRegData; 122 123 /** 124 * CRC info structure. 125 */ 126 typedef struct { 127 CCrcRegData crcRegData[MAX_CRC_REGS]; /*!< Multiple crc region description. */ 128 const USHORT* 129 pCrcLookup; /*!< Pointer to lookup table filled in FDK_crcInit(). */ 130 131 USHORT crcPoly; /*!< CRC generator polynom. */ 132 USHORT crcMask; /*!< CRC mask. */ 133 USHORT startValue; /*!< CRC start value. */ 134 UCHAR crcLen; /*!< CRC length. */ 135 136 UINT regStart; /*!< Start region marker for synchronization. */ 137 UINT regStop; /*!< Stop region marker for synchronization. */ 138 139 USHORT crcValue; /*!< Crc value to be calculated. */ 140 141 } FDK_CRCINFO; 142 143 /** 144 * CRC info handle. 145 */ 146 typedef FDK_CRCINFO* HANDLE_FDK_CRCINFO; 147 148 /** 149 * \brief Initialize CRC structure. 150 * 151 * The function initializes existing crc info structure with denoted 152 * configuration. 153 * 154 * \param hCrcInfo Pointer to an outlying allocated crc info 155 * structure. 156 * \param crcPoly Configure crc polynom. 157 * \param crcStartValue Configure crc start value. 158 * \param crcLen Configure crc length. 159 * 160 * \return none 161 */ 162 void FDKcrcInit(HANDLE_FDK_CRCINFO hCrcInfo, const UINT crcPoly, 163 const UINT crcStartValue, const UINT crcLen); 164 165 /** 166 * \brief Reset CRC info structure. 167 * 168 * This function clears all intern states of the crc structure. 169 * 170 * \param hCrcInfo Pointer to crc info stucture. 171 * 172 * \return none 173 */ 174 void FDKcrcReset(HANDLE_FDK_CRCINFO hCrcInfo); 175 176 /** 177 * \brief Start CRC region with maximum number of bits. 178 * 179 * This function marks position in bitstream to be used as start point for crc 180 * calculation. Bitstream range for crc calculation can be limited or kept 181 * dynamic depending on mBits parameter. The crc region has to be terminated 182 * with FDKcrcEndReg() in each case. 183 * 184 * \param hCrcInfo Pointer to crc info stucture. 185 * \param hBs Pointer to current bit buffer structure. 186 * \param mBits Number of bits in crc region to be calculated. 187 * - mBits > 0: Zero padding will be used for CRC 188 * calculation, if there are less than mBits bits available. 189 * - mBits < 0: No zero padding is done. 190 * - mBits = 0: The number of bits used in crc 191 * calculation is dynamically, depending on bitstream position between 192 * FDKcrcStartReg() and FDKcrcEndReg() 193 * call. 194 * 195 * \return ID for the created region, -1 in case of an error 196 */ 197 INT FDKcrcStartReg(HANDLE_FDK_CRCINFO hCrcInfo, const HANDLE_FDK_BITSTREAM hBs, 198 const INT mBits); 199 200 /** 201 * \brief Ends CRC region. 202 * 203 * This function terminates crc region specified with FDKcrcStartReg(). The 204 * number of bits in crc region depends on mBits parameter of FDKcrcStartReg(). 205 * This function calculates and updates crc in info structure. 206 * 207 * \param hCrcInfo Pointer to crc info stucture. 208 * \param hBs Pointer to current bit buffer structure. 209 * \param reg Crc region ID created in FDKcrcStartReg(). 210 * 211 * \return 0 on success 212 */ 213 INT FDKcrcEndReg(HANDLE_FDK_CRCINFO hCrcInfo, const HANDLE_FDK_BITSTREAM hBs, 214 const INT reg); 215 216 /** 217 * \brief This function returns crc value from info struct. 218 * 219 * \param hCrcInfo Pointer to crc info stucture. 220 * 221 * \return CRC value masked with crc length. 222 */ 223 USHORT FDKcrcGetCRC(const HANDLE_FDK_CRCINFO hCrcInfo); 224 225 #endif /* FDK_CRC_H */ 226