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Change-Id: I42a702487e6db4953dca0027710ea4fe266052fd Also: - Removed dead code in several source files. - Minor changes in comments. - No functional changes. No changes in executed code. - Added documentation PDFs.
323 lines
12 KiB
C
323 lines
12 KiB
C
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/* -----------------------------------------------------------------------------------------------------------
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Software License for The Fraunhofer FDK AAC Codec Library for Android
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© Copyright 1995 - 2012 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
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All rights reserved.
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1. INTRODUCTION
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The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
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the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
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This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
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AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
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audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
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independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
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of the MPEG specifications.
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Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
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may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
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individually for the purpose of encoding or decoding bit streams in products that are compliant with
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the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
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these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
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software may already be covered under those patent licenses when it is used for those licensed purposes only.
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Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
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are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
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applications information and documentation.
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2. COPYRIGHT LICENSE
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Redistribution and use in source and binary forms, with or without modification, are permitted without
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payment of copyright license fees provided that you satisfy the following conditions:
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You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
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your modifications thereto in source code form.
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You must retain the complete text of this software license in the documentation and/or other materials
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provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
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You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
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modifications thereto to recipients of copies in binary form.
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The name of Fraunhofer may not be used to endorse or promote products derived from this library without
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prior written permission.
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You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
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software or your modifications thereto.
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Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
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and the date of any change. For modified versions of the FDK AAC Codec, the term
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"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
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"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
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3. NO PATENT LICENSE
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NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
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ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
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respect to this software.
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You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
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by appropriate patent licenses.
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4. DISCLAIMER
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This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
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"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
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of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
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CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
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including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
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or business interruption, however caused and on any theory of liability, whether in contract, strict
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liability, or tort (including negligence), arising in any way out of the use of this software, even if
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advised of the possibility of such damage.
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5. CONTACT INFORMATION
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Fraunhofer Institute for Integrated Circuits IIS
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Attention: Audio and Multimedia Departments - FDK AAC LL
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Am Wolfsmantel 33
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91058 Erlangen, Germany
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www.iis.fraunhofer.de/amm
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amm-info@iis.fraunhofer.de
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----------------------------------------------------------------------------------------------------------- */
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/***************************** MPEG-4 AAC Decoder **************************
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Author(s): Josef Hoepfl
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Description: long/short-block decoding
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******************************************************************************/
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#ifndef BLOCK_H
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#define BLOCK_H
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#include "common_fix.h"
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#include "channelinfo.h"
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#include "FDK_bitstream.h"
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/* PNS (of block) */
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void CPns_Read (CPnsData *pPnsData,
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HANDLE_FDK_BITSTREAM bs,
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const CodeBookDescription *hcb,
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SHORT *pScaleFactor,
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UCHAR global_gain,
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int band,
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int group);
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void CPns_Apply (const CPnsData *pPnsData,
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const CIcsInfo *pIcsInfo,
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SPECTRAL_PTR pSpectrum,
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const SHORT *pSpecScale,
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const SHORT *pScaleFactor,
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const SamplingRateInfo *pSamplingRateInfo,
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const INT granuleLength,
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const int channel);
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/* TNS (of block) */
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/*!
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\brief Read tns data-present flag from bitstream
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The function reads the data-present flag for tns from
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the bitstream.
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\return none
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*/
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void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs,
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CTnsData *pTnsData);
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void CTns_ReadDataPresentUsac(
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HANDLE_FDK_BITSTREAM hBs,
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CTnsData *pTnsData0,
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CTnsData *pTnsData1,
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const CIcsInfo *pIcsInfo,
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const UINT flags,
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const int fCommonWindow
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);
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AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs,
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CTnsData *pTnsData,
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const CIcsInfo *pIcsInfo,
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const UINT flags);
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void CTns_Apply ( CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */
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const CIcsInfo *pIcsInfo,
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SPECTRAL_PTR pSpectralCoefficient,
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const SamplingRateInfo *pSamplingRateInfo,
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const INT granuleLength);
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/* Block */
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LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, const LONG q);
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/**
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* \brief Read scale factor data. See chapter 4.6.2.3.2 of ISO/IEC 14496-3.
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* The SF_OFFSET = 100 value referenced in chapter 4.6.2.3.3 is already substracted
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* from the scale factor values. Also includes PNS data reading.
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* \param bs bit stream handle data source
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* \param pAacDecoderChannelInfo channel context info were decoded data is stored into.
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* \param flags the decoder flags.
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*/
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AAC_DECODER_ERROR CBlock_ReadScaleFactorData(
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CAacDecoderChannelInfo *pAacDecoderChannelInfo,
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HANDLE_FDK_BITSTREAM bs,
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const UINT flags
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);
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/**
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* \brief Read Huffman encoded spectral data.
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* \param pAacDecoderChannelInfo channel context info.
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* \param pSamplingRateInfo sampling rate info (sfb offsets).
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* \param flags syntax flags.
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*/
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AAC_DECODER_ERROR CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs,
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CAacDecoderChannelInfo *pAacDecoderChannelInfo,
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const SamplingRateInfo *pSamplingRateInfo,
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const UINT flags);
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AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs,
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CAacDecoderChannelInfo *pAacDecoderChannelInfo,
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const SamplingRateInfo *pSamplingRateInfo,
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const UINT flags);
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/**
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* \brief find a common exponent (shift factor) for all sfb in each Spectral window, and store them into
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* CAacDecoderChannelInfo::specScale.
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* \param pAacDecoderChannelInfo channel context info.
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* \param pSamplingRateInfo sampling rate info (sfb offsets).
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*/
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void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
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/**
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* \brief Apply TNS and PNS tools.
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*/
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void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[],
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const SamplingRateInfo *pSamplingRateInfo,
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const UINT flags,
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const int channel );
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/**
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* \brief Transform MDCT spectral data into time domain
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*/
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void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
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CAacDecoderChannelInfo *pAacDecoderChannelInfo,
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INT_PCM outSamples[],
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const SHORT frameLen,
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const int stride,
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const int frameOk,
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FIXP_DBL *pWorkBuffer1);
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/**
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* \brief Transform double lapped MDCT (AAC-ELD) spectral data into time domain.
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*/
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void CBlock_FrequencyToTimeLowDelay(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
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CAacDecoderChannelInfo *pAacDecoderChannelInfo,
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INT_PCM outSamples[],
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const short frameLen,
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const char stride);
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AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
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/**
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* \brief Calculate 2^(lsb/4) * value^(4/3)
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* \param pValue pointer to quantized value. The inverse quantized result is stored back here.
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* \param lsb 2 LSBs of the scale factor (scaleFactor % 4) applied as power 2 factor to the
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* resulting inverse quantized value.
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* \return the exponent of the result (mantissa) stored into *pValue.
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*/
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FDK_INLINE
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int EvaluatePower43 ( FIXP_DBL *pValue,
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UINT lsb )
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{
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FIXP_DBL value;
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UINT freeBits;
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UINT exponent;
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value = *pValue;
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freeBits = fNormz (value) ;
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exponent = DFRACT_BITS - freeBits ;
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FDK_ASSERT (exponent < 14);
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UINT x = (((int)value << freeBits) >> 19) ;
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UINT tableIndex = (x & 0x0FFF) >> 4 ;
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FIXP_DBL invQVal ;
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x = x & 0x0F;
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UINT r0=(LONG)InverseQuantTable [tableIndex+0];
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UINT r1=(LONG)InverseQuantTable [tableIndex+1];
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USHORT nx=16-x;
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UINT temp=(r0)*nx+(r1)*x;
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invQVal = (FIXP_DBL)temp;
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FDK_ASSERT(lsb < 4);
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*pValue = fMultDiv2 (invQVal, MantissaTable [lsb][exponent]) ;
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/* + 1 compensates fMultDiv2(). */
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return ExponentTable [lsb][exponent] + 1;
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}
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/**
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* \brief determine the required shift scale for the given quantized value and scale (factor % 4) value.
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*/
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FDK_INLINE int GetScaleFromValue (FIXP_DBL value, unsigned int lsb)
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{
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if (value!=(FIXP_DBL)0)
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{
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int scale = EvaluatePower43 (&value, lsb) ;
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return CntLeadingZeros (value) - scale - 2 ;
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}
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else
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return 0; /* Return zero, because its useless to scale a zero value, saves workload and avoids scaling overshifts. */
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}
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//#ifdef AACDEC_HUFFMANDECODER_ENABLE
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/*!
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\brief Read huffman codeword
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The function reads the huffman codeword from the bitstream and
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returns the index value.
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\return index value
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*/
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inline int CBlock_DecodeHuffmanWord( HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */
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const CodeBookDescription *hcb ) /*!< pointer to codebook description */
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{
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UINT val;
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UINT index = 0;
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const USHORT (*CodeBook) [HuffmanEntries] = hcb->CodeBook;
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while (1)
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{
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val = CodeBook[index][FDKreadBits(bs,HuffmanBits)]; /* Expensive memory access */
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if ((val & 1) == 0)
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{
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index = val>>2;
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continue;
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}
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else
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{
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if (val & 2)
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{
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FDKpushBackCache(bs,1);
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}
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val >>= 2;
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break;
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}
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}
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return val;
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}
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//#endif /* AACDEC_HUFFMANDECODER_ENABLE */
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#endif /* #ifndef BLOCK_H */
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