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Diffstat (limited to 'libSBRenc/src/env_bit.cpp')
| -rw-r--r-- | libSBRenc/src/env_bit.cpp | 250 |
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diff --git a/libSBRenc/src/env_bit.cpp b/libSBRenc/src/env_bit.cpp new file mode 100644 index 0000000..55c6967 --- /dev/null +++ b/libSBRenc/src/env_bit.cpp @@ -0,0 +1,250 @@ + +/* ----------------------------------------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2012 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. + All rights reserved. + + 1. INTRODUCTION +The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements +the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio. +This FDK AAC Codec software is intended to be used on a wide variety of Android devices. + +AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual +audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by +independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part +of the MPEG specifications. + +Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer) +may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners +individually for the purpose of encoding or decoding bit streams in products that are compliant with +the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license +these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec +software may already be covered under those patent licenses when it is used for those licensed purposes only. + +Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality, +are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional +applications information and documentation. + +2. COPYRIGHT LICENSE + +Redistribution and use in source and binary forms, with or without modification, are permitted without +payment of copyright license fees provided that you satisfy the following conditions: + +You must retain the complete text of this software license in redistributions of the FDK AAC Codec or +your modifications thereto in source code form. + +You must retain the complete text of this software license in the documentation and/or other materials +provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form. +You must make available free of charge copies of the complete source code of the FDK AAC Codec and your +modifications thereto to recipients of copies in binary form. + +The name of Fraunhofer may not be used to endorse or promote products derived from this library without +prior written permission. + +You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec +software or your modifications thereto. + +Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software +and the date of any change. For modified versions of the FDK AAC Codec, the term +"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term +"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android." + +3. NO PATENT LICENSE + +NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, +ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with +respect to this software. + +You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized +by appropriate patent licenses. + +4. DISCLAIMER + +This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors +"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties +of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR +CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages, +including but not limited to procurement of substitute goods or services; loss of use, data, or profits, +or business interruption, however caused and on any theory of liability, whether in contract, strict +liability, or tort (including negligence), arising in any way out of the use of this software, even if +advised of the possibility of such damage. + +5. CONTACT INFORMATION + +Fraunhofer Institute for Integrated Circuits IIS +Attention: Audio and Multimedia Departments - FDK AAC LL +Am Wolfsmantel 33 +91058 Erlangen, Germany + +www.iis.fraunhofer.de/amm +amm-info@iis.fraunhofer.de +----------------------------------------------------------------------------------------------------------- */ + +/*! + \file + \brief Remaining SBR Bit Writing Routines +*/ + +#include "env_bit.h" +#include "cmondata.h" + + +#ifndef min +#define min(a,b) ( a < b ? a:b) +#endif + +#ifndef max +#define max(a,b) ( a > b ? a:b) +#endif + +/* ***************************** crcAdvance **********************************/ +/** + * @fn + * @brief updates crc data register + * @return none + * + * This function updates the crc register + * + */ +static void crcAdvance(USHORT crcPoly, + USHORT crcMask, + USHORT *crc, + ULONG bValue, + INT bBits + ) +{ + INT i; + USHORT flag; + + for (i=bBits-1; i>=0; i--) { + flag = ((*crc) & crcMask) ? (1) : (0) ; + flag ^= (bValue & (1<<i)) ? (1) : (0) ; + + (*crc)<<=1; + if(flag) (*crc) ^= crcPoly; + } +} + + +/* ***************************** FDKsbrEnc_InitSbrBitstream **********************************/ +/** + * @fn + * @brief Inittialisation of sbr bitstream, write of dummy header and CRC + * @return none + * + * + * + */ + +INT FDKsbrEnc_InitSbrBitstream(HANDLE_COMMON_DATA hCmonData, + UCHAR *memoryBase, /*!< Pointer to bitstream buffer */ + INT memorySize, /*!< Length of bitstream buffer in bytes */ + HANDLE_FDK_CRCINFO hCrcInfo, + UINT sbrSyntaxFlags) /*!< SBR syntax flags */ +{ + INT crcRegion = 0; + + /* reset bit buffer */ + FDKresetBitbuffer(&hCmonData->sbrBitbuf, BS_WRITER); + + FDKinitBitStream(&hCmonData->tmpWriteBitbuf, memoryBase, + memorySize, 0, BS_WRITER); + + if (sbrSyntaxFlags & SBR_SYNTAX_CRC) { + if (sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC) + { /* Init and start CRC region */ + FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_DRM_CRC_BITS); + FDKcrcInit( hCrcInfo, 0x001d, 0xFFFF, SI_SBR_DRM_CRC_BITS ); + crcRegion = FDKcrcStartReg( hCrcInfo, &hCmonData->sbrBitbuf, 0 ); + } else { + FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_CRC_BITS); + } + } + + return (crcRegion); +} + + +/* ************************** FDKsbrEnc_AssembleSbrBitstream *******************************/ +/** + * @fn + * @brief Formats the SBR payload + * @return nothing + * + * Also the CRC will be calculated here. + * + */ + +void +FDKsbrEnc_AssembleSbrBitstream( HANDLE_COMMON_DATA hCmonData, + HANDLE_FDK_CRCINFO hCrcInfo, + INT crcRegion, + UINT sbrSyntaxFlags) +{ + USHORT crcReg = SBR_CRCINIT; + INT numCrcBits,i; + + /* check if SBR is present */ + if ( hCmonData==NULL ) + return; + + hCmonData->sbrFillBits = 0; /* Fill bits are written only for GA streams */ + + if ( sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC ) + { + /* + * Calculate and write DRM CRC + */ + FDKcrcEndReg( hCrcInfo, &hCmonData->sbrBitbuf, crcRegion ); + FDKwriteBits( &hCmonData->tmpWriteBitbuf, FDKcrcGetCRC(hCrcInfo)^0xFF, SI_SBR_DRM_CRC_BITS ); + } + else + { + if ( !(sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) ) + { + /* Do alignment here, because its defined as part of the sbr_extension_data */ + int sbrLoad = hCmonData->sbrHdrBits + hCmonData->sbrDataBits; + + if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) { + sbrLoad += SI_SBR_CRC_BITS; + } + + sbrLoad += 4; /* Do byte Align with 4 bit offset. ISO/IEC 14496-3:2005(E) page 39. */ + + hCmonData->sbrFillBits = (8 - (sbrLoad % 8)) % 8; + + /* + append fill bits + */ + FDKwriteBits(&hCmonData->sbrBitbuf, 0, hCmonData->sbrFillBits ); + + FDK_ASSERT(FDKgetValidBits(&hCmonData->sbrBitbuf) % 8 == 4); + } + + /* + calculate crc + */ + if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) { + FDK_BITSTREAM tmpCRCBuf = hCmonData->sbrBitbuf; + FDKresetBitbuffer( &tmpCRCBuf, BS_READER ); + + numCrcBits = hCmonData->sbrHdrBits + hCmonData->sbrDataBits + hCmonData->sbrFillBits; + + for(i=0;i<numCrcBits;i++){ + INT bit; + bit = FDKreadBits(&tmpCRCBuf,1); + crcAdvance(SBR_CRC_POLY,SBR_CRC_MASK,&crcReg,bit,1); + } + crcReg &= (SBR_CRC_RANGE); + + /* + * Write CRC data. + */ + FDKwriteBits (&hCmonData->tmpWriteBitbuf, crcReg, SI_SBR_CRC_BITS); + } + } + + FDKsyncCache(&hCmonData->tmpWriteBitbuf); +} + |