1 2/* ----------------------------------------------------------------------------------------------------------- 3Software License for The Fraunhofer FDK AAC Codec Library for Android 4 5� Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V. 6 All rights reserved. 7 8 1. INTRODUCTION 9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements 10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio. 11This FDK AAC Codec software is intended to be used on a wide variety of Android devices. 12 13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual 14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by 15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part 16of the MPEG specifications. 17 18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer) 19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners 20individually for the purpose of encoding or decoding bit streams in products that are compliant with 21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license 22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec 23software may already be covered under those patent licenses when it is used for those licensed purposes only. 24 25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality, 26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional 27applications information and documentation. 28 292. COPYRIGHT LICENSE 30 31Redistribution and use in source and binary forms, with or without modification, are permitted without 32payment of copyright license fees provided that you satisfy the following conditions: 33 34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or 35your modifications thereto in source code form. 36 37You must retain the complete text of this software license in the documentation and/or other materials 38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form. 39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your 40modifications thereto to recipients of copies in binary form. 41 42The name of Fraunhofer may not be used to endorse or promote products derived from this library without 43prior written permission. 44 45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec 46software or your modifications thereto. 47 48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software 49and 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." 52 533. NO PATENT LICENSE 54 55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, 56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with 57respect to this software. 58 59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized 60by appropriate patent licenses. 61 624. DISCLAIMER 63 64This 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 66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages, 68including but not limited to procurement of substitute goods or services; loss of use, data, or profits, 69or business interruption, however caused and on any theory of liability, whether in contract, strict 70liability, or tort (including negligence), arising in any way out of the use of this software, even if 71advised of the possibility of such damage. 72 735. CONTACT INFORMATION 74 75Fraunhofer Institute for Integrated Circuits IIS 76Attention: Audio and Multimedia Departments - FDK AAC LL 77Am Wolfsmantel 33 7891058 Erlangen, Germany 79 80www.iis.fraunhofer.de/amm 81amm-info@iis.fraunhofer.de 82----------------------------------------------------------------------------------------------------------- */ 83 84/******************************** MPEG Audio Encoder ************************** 85 86 Initial author: 87 contents/description: CRC calculation 88 89******************************************************************************/ 90 91#ifndef FDK_CRC_H 92#define FDK_CRC_H 93 94 95 96#include "FDK_bitstream.h" 97 98 99#define MAX_CRC_REGS 3 /*!< Maximal number of overlapping crc region in ADTS channel pair element is two. 100 Select three independent regions preventively. */ 101 102/** 103 * This structure describes single crc region used for crc calculation. 104 */ 105typedef struct 106{ 107 UCHAR isActive; 108 INT maxBits; 109 UINT bitBufCntBits; 110 UINT validBits; 111 112} CCrcRegData; 113 114/** 115 * CRC info structure. 116 */ 117typedef struct 118{ 119 CCrcRegData crcRegData[MAX_CRC_REGS]; /*!< Multiple crc region description. */ 120 const USHORT *pCrcLookup; /*!< Pointer to lookup table filled in FDK_crcInit(). */ 121 122 USHORT crcPoly; /*!< CRC generator polynom. */ 123 USHORT crcMask; /*!< CRC mask. */ 124 USHORT startValue; /*!< CRC start value. */ 125 UCHAR crcLen; /*!< CRC length. */ 126 127 UINT regStart; /*!< Start region marker for synchronization. */ 128 UINT regStop; /*!< Stop region marker for synchronization. */ 129 130 USHORT crcValue; /*!< Crc value to be calculated. */ 131 132} FDK_CRCINFO; 133 134/** 135 * CRC info handle. 136 */ 137typedef FDK_CRCINFO* HANDLE_FDK_CRCINFO; 138 139 140/** 141 * \brief Initialize CRC structure. 142 * 143 * The function initializes existing crc info structure with denoted configuration. 144 * 145 * \param hCrcInfo Pointer to an outlying allocated crc info structure. 146 * \param crcPoly Configure crc polynom. 147 * \param crcStartValue Configure crc start value. 148 * \param crcLen Configure crc length. 149 * 150 * \return none 151 */ 152void FDKcrcInit( 153 HANDLE_FDK_CRCINFO hCrcInfo, 154 const UINT crcPoly, 155 const UINT crcStartValue, 156 const UINT crcLen 157 ); 158 159/** 160 * \brief Reset CRC info structure. 161 * 162 * This function clears all intern states of the crc structure. 163 * 164 * \param hCrcInfo Pointer to crc info stucture. 165 * 166 * \return none 167 */ 168void FDKcrcReset( 169 HANDLE_FDK_CRCINFO hCrcInfo 170 ); 171 172 173/** 174 * \brief Start CRC region with maximum number of bits. 175 * 176 * This function marks position in bitstream to be used as start point for crc calculation. 177 * Bitstream range for crc calculation can be limited or kept dynamic depending on mBits parameter. 178 * The crc region has to be terminated with FDKcrcEndReg() in each case. 179 * 180 * \param hCrcInfo Pointer to crc info stucture. 181 * \param hBs Pointer to current bit buffer structure. 182 * \param mBits Number of bits in crc region to be calculated. 183 * - mBits > 0: Zero padding will be used for CRC calculation, if there 184 * are less than mBits bits available. 185 * - mBits < 0: No zero padding is done. 186 * - mBits = 0: The number of bits used in crc calculation is dynamically, 187 * depending on bitstream position between FDKcrcStartReg() and 188 * FDKcrcEndReg() call. 189 * 190 * \return ID for the created region, -1 in case of an error 191 */ 192INT FDKcrcStartReg( 193 HANDLE_FDK_CRCINFO hCrcInfo, 194 const HANDLE_FDK_BITSTREAM hBs, 195 const INT mBits 196 ); 197 198 199/** 200 * \brief Ends CRC region. 201 * 202 * This function terminates crc region specified with FDKcrcStartReg(). The number of bits in crc region depends 203 * on mBits parameter of FDKcrcStartReg(). 204 * This function calculates and updates crc in info structure. 205 * 206 * \param hCrcInfo Pointer to crc info stucture. 207 * \param hBs Pointer to current bit buffer structure. 208 * \param reg Crc region ID created in FDKcrcStartReg(). 209 * 210 * \return 0 on success 211 */ 212INT FDKcrcEndReg( 213 HANDLE_FDK_CRCINFO hCrcInfo, 214 const HANDLE_FDK_BITSTREAM hBs, 215 const INT reg 216 ); 217 218 219/** 220 * \brief This function returns crc value from info struct. 221 * 222 * \param hCrcInfo Pointer to crc info stucture. 223 * 224 * \return CRC value masked with crc length. 225 */ 226USHORT FDKcrcGetCRC( 227 const HANDLE_FDK_CRCINFO hCrcInfo 228 ); 229 230 231#endif /* FDK_CRC_H */ 232