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Diffstat (limited to 'libAACdec/src/aacdec_tns.cpp')
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diff --git a/libAACdec/src/aacdec_tns.cpp b/libAACdec/src/aacdec_tns.cpp new file mode 100644 index 0000000..db67c9b --- /dev/null +++ b/libAACdec/src/aacdec_tns.cpp @@ -0,0 +1,412 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------------------------------------- */ + +/***************************** MPEG-4 AAC Decoder ************************** + + Author(s): Josef Hoepfl + Description: temporal noise shaping tool + +******************************************************************************/ + +#include "aacdec_tns.h" +#include "aac_rom.h" +#include "FDK_bitstream.h" +#include "channelinfo.h" + + + +/*! + \brief Reset tns data + + The function resets the tns data + + \return none +*/ +void CTns_Reset(CTnsData *pTnsData) +{ + /* Note: the following FDKmemclear should not be required. */ + FDKmemclear(pTnsData->Filter, TNS_MAX_WINDOWS*TNS_MAXIMUM_FILTERS*sizeof(CFilter)); + FDKmemclear(pTnsData->NumberOfFilters, TNS_MAX_WINDOWS*sizeof(UCHAR)); + pTnsData->DataPresent = 0; + pTnsData->Active = 0; +} + +void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */ + CTnsData *pTnsData) /*!< pointer to aac decoder channel info */ +{ + pTnsData->DataPresent = (UCHAR) FDKreadBits(bs,1); +} + +/*! + \brief Read tns data from bitstream + + The function reads the elements for tns from + the bitstream. + + \return none +*/ +AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs, + CTnsData *pTnsData, + const CIcsInfo *pIcsInfo, + const UINT flags) +{ + UCHAR n_filt,order; + UCHAR length,coef_res,coef_compress; + UCHAR window; + UCHAR wins_per_frame = GetWindowsPerFrame(pIcsInfo); + UCHAR isLongFlag = IsLongBlock(pIcsInfo); + AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK; + + if (!pTnsData->DataPresent) { + return ErrorStatus; + } + + for (window = 0; window < wins_per_frame; window++) + { + pTnsData->NumberOfFilters[window] = n_filt = (UCHAR) FDKreadBits(bs, isLongFlag ? 2 : 1); + + if (pTnsData->NumberOfFilters[window] > TNS_MAXIMUM_FILTERS){ + pTnsData->NumberOfFilters[window] = n_filt = TNS_MAXIMUM_FILTERS; + } + + if (n_filt) + { + int index; + UCHAR nextstopband; + + coef_res = (UCHAR) FDKreadBits(bs,1); + + nextstopband = GetScaleFactorBandsTotal(pIcsInfo); + + for (index=0; index < n_filt; index++) + { + CFilter *filter = &pTnsData->Filter[window][index]; + + length = (UCHAR)FDKreadBits(bs, isLongFlag ? 6 : 4); + + if (length > nextstopband){ + length = nextstopband; + } + + filter->StartBand = nextstopband - length; + filter->StopBand = nextstopband; + nextstopband = filter->StartBand; + + { + filter->Order = order = (UCHAR) FDKreadBits(bs, isLongFlag ? 5 : 3); + } + + if (filter->Order > TNS_MAXIMUM_ORDER){ + filter->Order = order = TNS_MAXIMUM_ORDER; + } + + if (order) + { + UCHAR coef,s_mask; + UCHAR i; + SCHAR n_mask; + static const UCHAR sgn_mask[] = { 0x2, 0x4, 0x8 }; + static const SCHAR neg_mask[] = { ~0x3, ~0x7, ~0xF }; + + filter->Direction = FDKreadBits(bs,1) ? -1 : 1; + + coef_compress = (UCHAR) FDKreadBits(bs,1); + + filter->Resolution = coef_res + 3; + + s_mask = sgn_mask[coef_res + 1 - coef_compress]; + n_mask = neg_mask[coef_res + 1 - coef_compress]; + + for (i=0; i < order; i++) + { + coef = (UCHAR) FDKreadBits(bs,filter->Resolution - coef_compress); + filter->Coeff[i] = (coef & s_mask) ? (coef | n_mask) : coef; + } + } + } + } + } + + pTnsData->Active = 1; + + return ErrorStatus; +} + + +static void CTns_Filter (FIXP_DBL *spec, int size, int inc, FIXP_TCC coeff [], int order) +{ + // - Simple all-pole filter of order "order" defined by + // y(n) = x(n) - a(2)*y(n-1) - ... - a(order+1)*y(n-order) + // + // - The state variables of the filter are initialized to zero every time + // + // - The output data is written over the input data ("in-place operation") + // + // - An input vector of "size" samples is processed and the index increment + // to the next data sample is given by "inc" + + int i,j,N; + FIXP_DBL *pSpec; + FIXP_DBL maxVal=FL2FXCONST_DBL(0.0); + INT s; + + FDK_ASSERT(order <= TNS_MAXIMUM_ORDER); + C_ALLOC_SCRATCH_START(state, FIXP_DBL, TNS_MAXIMUM_ORDER); + FDKmemclear(state, order*sizeof(FIXP_DBL)); + + for (i=0; i<size; i++) { + maxVal = fixMax(maxVal,fixp_abs(spec[i])); + } + + if ( maxVal > FL2FXCONST_DBL(0.03125*0.70710678118) ) + s = fixMax(CntLeadingZeros(maxVal)-6,0); + else + s = fixMax(CntLeadingZeros(maxVal)-5,0); + + s = fixMin(s,2); + s = s-1; + + if (inc == -1) + pSpec = &spec[size - 1]; + else + pSpec = &spec[0]; + + FIXP_TCC *pCoeff; + +#define FIRST_PART_FLTR \ + FIXP_DBL x, *pState = state; \ + pCoeff = coeff; \ + \ + if (s < 0) \ + x = (pSpec [0]>>1) + fMultDiv2 (*pCoeff++, pState [0]) ; \ + else \ + x = (pSpec [0]<<s) + fMultDiv2 (*pCoeff++, pState [0]) ; + +#define INNER_FLTR_INLINE \ + x = fMultAddDiv2 (x, *pCoeff, pState [1]); \ + pState [0] = pState [1] - (fMultDiv2 (*pCoeff++, x) <<2) ; \ + pState++; + +#define LAST_PART_FLTR \ + if (s < 0) \ + *pSpec = x << 1; \ + else \ + *pSpec = x >> s; \ + *pState =(-x) << 1; \ + pSpec += inc ; + + + if (order>8) + { + N = (order-1)&7; + + for (i = size ; i != 0 ; i--) + { + FIRST_PART_FLTR + + for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } + + INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE + INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE + + LAST_PART_FLTR + } + + } else if (order>4) { + + N = (order-1)&3; + + for (i = size ; i != 0 ; i--) + { + FIRST_PART_FLTR + for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } + + INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE INNER_FLTR_INLINE + + LAST_PART_FLTR + } + + } else { + + N = order-1; + + for (i = size ; i != 0 ; i--) + { + FIRST_PART_FLTR + + for (j = N; j > 0 ; j--) { INNER_FLTR_INLINE } + + LAST_PART_FLTR + } + } + + C_ALLOC_SCRATCH_END(state, FIXP_DBL, TNS_MAXIMUM_ORDER); +} + +/*! + \brief Apply tns to spectral lines + + The function applies the tns to the spectrum, + + \return none +*/ +void CTns_Apply ( + CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */ + const CIcsInfo *pIcsInfo, + SPECTRAL_PTR pSpectralCoefficient, + const SamplingRateInfo *pSamplingRateInfo, + const INT granuleLength + ) +{ + int window,index,start,stop,size; + + + if (pTnsData->Active) + { + C_AALLOC_SCRATCH_START(coeff, FIXP_TCC, TNS_MAXIMUM_ORDER); + + for (window=0; window < GetWindowsPerFrame(pIcsInfo); window++) + { + FIXP_DBL *pSpectrum = SPEC(pSpectralCoefficient, window, granuleLength); + + for (index=0; index < pTnsData->NumberOfFilters[window]; index++) + { + CFilter *RESTRICT filter = &pTnsData->Filter[window][index]; + + if (filter->Order > 0) + { + FIXP_TCC *pCoeff; + int tns_max_bands; + + pCoeff = &coeff[filter->Order-1]; + if (filter->Resolution == 3) + { + int i; + for (i=0; i < filter->Order; i++) + *pCoeff-- = FDKaacDec_tnsCoeff3[filter->Coeff[i]+4]; + } + else + { + int i; + for (i=0; i < filter->Order; i++) + *pCoeff-- = FDKaacDec_tnsCoeff4[filter->Coeff[i]+8]; + } + + switch (granuleLength) { + case 480: + tns_max_bands = tns_max_bands_tbl_480[pSamplingRateInfo->samplingRateIndex-3]; + break; + case 512: + tns_max_bands = tns_max_bands_tbl_512[pSamplingRateInfo->samplingRateIndex-3]; + break; + default: + tns_max_bands = GetMaximumTnsBands(pIcsInfo, pSamplingRateInfo->samplingRateIndex); + break; + } + + start = fixMin( fixMin(filter->StartBand, tns_max_bands), + GetScaleFactorBandsTransmitted(pIcsInfo) ); + + start = GetScaleFactorBandOffsets(pIcsInfo, pSamplingRateInfo)[start]; + + stop = fixMin( fixMin(filter->StopBand, tns_max_bands), + GetScaleFactorBandsTransmitted(pIcsInfo) ); + + stop = GetScaleFactorBandOffsets(pIcsInfo, pSamplingRateInfo)[stop]; + + size = stop - start; + + if (size > 0) { + CTns_Filter(&pSpectrum[start], + size, + filter->Direction, + coeff, + filter->Order ); + } + } + } + } + C_AALLOC_SCRATCH_END(coeff, FIXP_TCC, TNS_MAXIMUM_ORDER); + } + +} |