| |
| /* ----------------------------------------------------------------------------------------------------------- |
| Software License for The Fraunhofer FDK AAC Codec Library for Android |
| |
| © Copyright 1995 - 2013 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 |
| ----------------------------------------------------------------------------------------------------------- */ |
| |
| /***************************** MPEG-4 AAC Decoder ************************** |
| |
| Author(s): Josef Hoepfl |
| Description: long/short-block decoding |
| |
| ******************************************************************************/ |
| |
| #ifndef BLOCK_H |
| #define BLOCK_H |
| |
| #include "common_fix.h" |
| |
| #include "channelinfo.h" |
| #include "FDK_bitstream.h" |
| |
| /* PNS (of block) */ |
| void CPns_Read (CPnsData *pPnsData, |
| HANDLE_FDK_BITSTREAM bs, |
| const CodeBookDescription *hcb, |
| SHORT *pScaleFactor, |
| UCHAR global_gain, |
| int band, |
| int group); |
| |
| |
| void CPns_Apply (const CPnsData *pPnsData, |
| const CIcsInfo *pIcsInfo, |
| SPECTRAL_PTR pSpectrum, |
| const SHORT *pSpecScale, |
| const SHORT *pScaleFactor, |
| const SamplingRateInfo *pSamplingRateInfo, |
| const INT granuleLength, |
| const int channel); |
| |
| |
| |
| /* TNS (of block) */ |
| /*! |
| \brief Read tns data-present flag from bitstream |
| |
| The function reads the data-present flag for tns from |
| the bitstream. |
| |
| \return none |
| */ |
| void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs, |
| CTnsData *pTnsData); |
| |
| void CTns_ReadDataPresentUsac( |
| HANDLE_FDK_BITSTREAM hBs, |
| CTnsData *pTnsData0, |
| CTnsData *pTnsData1, |
| const CIcsInfo *pIcsInfo, |
| const UINT flags, |
| const int fCommonWindow |
| ); |
| |
| AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs, |
| CTnsData *pTnsData, |
| const CIcsInfo *pIcsInfo, |
| const UINT flags); |
| |
| void CTns_Apply ( CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */ |
| const CIcsInfo *pIcsInfo, |
| SPECTRAL_PTR pSpectralCoefficient, |
| const SamplingRateInfo *pSamplingRateInfo, |
| const INT granuleLength); |
| |
| /* Block */ |
| |
| LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, const LONG q); |
| |
| /** |
| * \brief Read scale factor data. See chapter 4.6.2.3.2 of ISO/IEC 14496-3. |
| * The SF_OFFSET = 100 value referenced in chapter 4.6.2.3.3 is already substracted |
| * from the scale factor values. Also includes PNS data reading. |
| * \param bs bit stream handle data source |
| * \param pAacDecoderChannelInfo channel context info were decoded data is stored into. |
| * \param flags the decoder flags. |
| */ |
| AAC_DECODER_ERROR CBlock_ReadScaleFactorData( |
| CAacDecoderChannelInfo *pAacDecoderChannelInfo, |
| HANDLE_FDK_BITSTREAM bs, |
| const UINT flags |
| ); |
| |
| /** |
| * \brief Read Huffman encoded spectral data. |
| * \param pAacDecoderChannelInfo channel context info. |
| * \param pSamplingRateInfo sampling rate info (sfb offsets). |
| * \param flags syntax flags. |
| */ |
| AAC_DECODER_ERROR CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs, |
| CAacDecoderChannelInfo *pAacDecoderChannelInfo, |
| const SamplingRateInfo *pSamplingRateInfo, |
| const UINT flags); |
| |
| |
| AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs, |
| CAacDecoderChannelInfo *pAacDecoderChannelInfo, |
| const SamplingRateInfo *pSamplingRateInfo, |
| const UINT flags); |
| |
| /** |
| * \brief find a common exponent (shift factor) for all sfb in each Spectral window, and store them into |
| * CAacDecoderChannelInfo::specScale. |
| * \param pAacDecoderChannelInfo channel context info. |
| * \param pSamplingRateInfo sampling rate info (sfb offsets). |
| */ |
| void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo); |
| |
| /** |
| * \brief Apply TNS and PNS tools. |
| */ |
| void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[], |
| const SamplingRateInfo *pSamplingRateInfo, |
| const UINT flags, |
| const int channel ); |
| |
| /** |
| * \brief Transform MDCT spectral data into time domain |
| */ |
| void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo, |
| CAacDecoderChannelInfo *pAacDecoderChannelInfo, |
| INT_PCM outSamples[], |
| const SHORT frameLen, |
| const int stride, |
| const int frameOk, |
| FIXP_DBL *pWorkBuffer1); |
| |
| /** |
| * \brief Transform double lapped MDCT (AAC-ELD) spectral data into time domain. |
| */ |
| void CBlock_FrequencyToTimeLowDelay(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo, |
| CAacDecoderChannelInfo *pAacDecoderChannelInfo, |
| INT_PCM outSamples[], |
| const short frameLen, |
| const char stride); |
| |
| AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo); |
| |
| /** |
| * \brief Calculate 2^(lsb/4) * value^(4/3) |
| * \param pValue pointer to quantized value. The inverse quantized result is stored back here. |
| * \param lsb 2 LSBs of the scale factor (scaleFactor % 4) applied as power 2 factor to the |
| * resulting inverse quantized value. |
| * \return the exponent of the result (mantissa) stored into *pValue. |
| */ |
| FDK_INLINE |
| int EvaluatePower43 ( FIXP_DBL *pValue, |
| UINT lsb ) |
| { |
| FIXP_DBL value; |
| UINT freeBits; |
| UINT exponent; |
| |
| value = *pValue; |
| freeBits = fNormz (value) ; |
| exponent = DFRACT_BITS - freeBits ; |
| FDK_ASSERT (exponent < 14); |
| |
| UINT x = (((int)value << freeBits) >> 19) ; |
| UINT tableIndex = (x & 0x0FFF) >> 4 ; |
| FIXP_DBL invQVal ; |
| |
| x = x & 0x0F; |
| |
| UINT r0=(LONG)InverseQuantTable [tableIndex+0]; |
| UINT r1=(LONG)InverseQuantTable [tableIndex+1]; |
| USHORT nx=16-x; |
| UINT temp=(r0)*nx+(r1)*x; |
| invQVal = (FIXP_DBL)temp; |
| |
| FDK_ASSERT(lsb < 4); |
| *pValue = fMultDiv2 (invQVal, MantissaTable [lsb][exponent]) ; |
| |
| /* + 1 compensates fMultDiv2(). */ |
| return ExponentTable [lsb][exponent] + 1; |
| } |
| |
| /** |
| * \brief determine the required shift scale for the given quantized value and scale (factor % 4) value. |
| */ |
| FDK_INLINE int GetScaleFromValue (FIXP_DBL value, unsigned int lsb) |
| { |
| if (value!=(FIXP_DBL)0) |
| { |
| int scale = EvaluatePower43 (&value, lsb) ; |
| return CntLeadingZeros (value) - scale - 2 ; |
| } |
| else |
| return 0; /* Return zero, because its useless to scale a zero value, saves workload and avoids scaling overshifts. */ |
| } |
| |
| |
| //#ifdef AACDEC_HUFFMANDECODER_ENABLE |
| |
| /*! |
| \brief Read huffman codeword |
| |
| The function reads the huffman codeword from the bitstream and |
| returns the index value. |
| |
| \return index value |
| */ |
| inline int CBlock_DecodeHuffmanWord( HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */ |
| const CodeBookDescription *hcb ) /*!< pointer to codebook description */ |
| { |
| UINT val; |
| UINT index = 0; |
| const USHORT (*CodeBook) [HuffmanEntries] = hcb->CodeBook; |
| |
| while (1) |
| { |
| val = CodeBook[index][FDKreadBits(bs,HuffmanBits)]; /* Expensive memory access */ |
| |
| if ((val & 1) == 0) |
| { |
| index = val>>2; |
| continue; |
| } |
| else |
| { |
| if (val & 2) |
| { |
| FDKpushBackCache(bs,1); |
| } |
| |
| val >>= 2; |
| break; |
| } |
| } |
| |
| return val; |
| } |
| |
| //#endif /* AACDEC_HUFFMANDECODER_ENABLE */ |
| |
| #endif /* #ifndef BLOCK_H */ |
