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Diffstat (limited to 'fdk-aac/libAACenc/src/band_nrg.cpp')
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diff --git a/fdk-aac/libAACenc/src/band_nrg.cpp b/fdk-aac/libAACenc/src/band_nrg.cpp new file mode 100644 index 0000000..fb22dbb --- /dev/null +++ b/fdk-aac/libAACenc/src/band_nrg.cpp @@ -0,0 +1,361 @@ +/* ----------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2018 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 +----------------------------------------------------------------------------- */ + +/**************************** AAC encoder library ****************************** + + Author(s): M. Werner + + Description: Band/Line energy calculations + +*******************************************************************************/ + +#include "band_nrg.h" + +/***************************************************************************** + functionname: FDKaacEnc_CalcSfbMaxScaleSpec + description: + input: + output: +*****************************************************************************/ +void FDKaacEnc_CalcSfbMaxScaleSpec(const FIXP_DBL *RESTRICT mdctSpectrum, + const INT *RESTRICT bandOffset, + INT *RESTRICT sfbMaxScaleSpec, + const INT numBands) { + INT i, j; + FIXP_DBL maxSpc, tmp; + + for (i = 0; i < numBands; i++) { + maxSpc = (FIXP_DBL)0; + + DWORD_ALIGNED(mdctSpectrum); + + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + tmp = fixp_abs(mdctSpectrum[j]); + maxSpc = fixMax(maxSpc, tmp); + } + j = CntLeadingZeros(maxSpc) - 1; + sfbMaxScaleSpec[i] = fixMin((DFRACT_BITS - 2), j); + /* CountLeadingBits() is not necessary here since test value is always > 0 + */ + } +} + +/***************************************************************************** + functionname: FDKaacEnc_CheckBandEnergyOptim + description: + input: + output: +*****************************************************************************/ +FIXP_DBL +FDKaacEnc_CheckBandEnergyOptim(const FIXP_DBL *const RESTRICT mdctSpectrum, + const INT *const RESTRICT sfbMaxScaleSpec, + const INT *const RESTRICT bandOffset, + const INT numBands, + FIXP_DBL *RESTRICT bandEnergy, + FIXP_DBL *RESTRICT bandEnergyLdData, + const INT minSpecShift) { + INT i, j, scale, nr = 0; + FIXP_DBL maxNrgLd = FL2FXCONST_DBL(-1.0f); + FIXP_DBL maxNrg = 0; + FIXP_DBL spec; + + for (i = 0; i < numBands; i++) { + scale = fixMax(0, sfbMaxScaleSpec[i] - 4); + FIXP_DBL tmp = 0; + + DWORD_ALIGNED(mdctSpectrum); + + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + spec = mdctSpectrum[j] << scale; + tmp = fPow2AddDiv2(tmp, spec); + } + bandEnergy[i] = tmp << 1; + + /* calculate ld of bandNrg, subtract scaling */ + bandEnergyLdData[i] = CalcLdData(bandEnergy[i]); + if (bandEnergyLdData[i] != FL2FXCONST_DBL(-1.0f)) { + bandEnergyLdData[i] -= scale * FL2FXCONST_DBL(2.0 / 64); + } + /* find index of maxNrg */ + if (bandEnergyLdData[i] > maxNrgLd) { + maxNrgLd = bandEnergyLdData[i]; + nr = i; + } + } + + /* return unscaled maxNrg*/ + scale = fixMax(0, sfbMaxScaleSpec[nr] - 4); + scale = fixMax(2 * (minSpecShift - scale), -(DFRACT_BITS - 1)); + + maxNrg = scaleValue(bandEnergy[nr], scale); + + return maxNrg; +} + +/***************************************************************************** + functionname: FDKaacEnc_CalcBandEnergyOptimLong + description: + input: + output: +*****************************************************************************/ +INT FDKaacEnc_CalcBandEnergyOptimLong(const FIXP_DBL *RESTRICT mdctSpectrum, + INT *RESTRICT sfbMaxScaleSpec, + const INT *RESTRICT bandOffset, + const INT numBands, + FIXP_DBL *RESTRICT bandEnergy, + FIXP_DBL *RESTRICT bandEnergyLdData) { + INT i, j, shiftBits = 0; + FIXP_DBL maxNrgLd = FL2FXCONST_DBL(0.0f); + + FIXP_DBL spec; + + for (i = 0; i < numBands; i++) { + INT leadingBits = sfbMaxScaleSpec[i] - + 4; /* max sfbWidth = 96 ; 2^7=128 => 7/2 = 4 (spc*spc) */ + FIXP_DBL tmp = FL2FXCONST_DBL(0.0); + /* don't use scaleValue() here, it increases workload quite sufficiently... + */ + if (leadingBits >= 0) { + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + spec = mdctSpectrum[j] << leadingBits; + tmp = fPow2AddDiv2(tmp, spec); + } + } else { + INT shift = -leadingBits; + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + spec = mdctSpectrum[j] >> shift; + tmp = fPow2AddDiv2(tmp, spec); + } + } + bandEnergy[i] = tmp << 1; + } + + /* calculate ld of bandNrg, subtract scaling */ + LdDataVector(bandEnergy, bandEnergyLdData, numBands); + for (i = numBands; i-- != 0;) { + FIXP_DBL scaleDiff = (sfbMaxScaleSpec[i] - 4) * FL2FXCONST_DBL(2.0 / 64); + + bandEnergyLdData[i] = (bandEnergyLdData[i] >= + ((FL2FXCONST_DBL(-1.f) >> 1) + (scaleDiff >> 1))) + ? bandEnergyLdData[i] - scaleDiff + : FL2FXCONST_DBL(-1.f); + /* find maxNrgLd */ + maxNrgLd = fixMax(maxNrgLd, bandEnergyLdData[i]); + } + + if (maxNrgLd <= (FIXP_DBL)0) { + for (i = numBands; i-- != 0;) { + INT scale = fixMin((sfbMaxScaleSpec[i] - 4) << 1, (DFRACT_BITS - 1)); + bandEnergy[i] = scaleValue(bandEnergy[i], -scale); + } + return 0; + } else { /* scale down NRGs */ + while (maxNrgLd > FL2FXCONST_DBL(0.0f)) { + maxNrgLd -= FL2FXCONST_DBL(2.0 / 64); + shiftBits++; + } + for (i = numBands; i-- != 0;) { + INT scale = fixMin(((sfbMaxScaleSpec[i] - 4) + shiftBits) << 1, + (DFRACT_BITS - 1)); + bandEnergyLdData[i] -= shiftBits * FL2FXCONST_DBL(2.0 / 64); + bandEnergy[i] = scaleValue(bandEnergy[i], -scale); + } + return shiftBits; + } +} + +/***************************************************************************** + functionname: FDKaacEnc_CalcBandEnergyOptimShort + description: + input: + output: +*****************************************************************************/ +void FDKaacEnc_CalcBandEnergyOptimShort(const FIXP_DBL *RESTRICT mdctSpectrum, + INT *RESTRICT sfbMaxScaleSpec, + const INT *RESTRICT bandOffset, + const INT numBands, + FIXP_DBL *RESTRICT bandEnergy) { + INT i, j; + + for (i = 0; i < numBands; i++) { + int leadingBits = sfbMaxScaleSpec[i] - + 3; /* max sfbWidth = 36 ; 2^6=64 => 6/2 = 3 (spc*spc) */ + FIXP_DBL tmp = FL2FXCONST_DBL(0.0); + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + FIXP_DBL spec = scaleValue(mdctSpectrum[j], leadingBits); + tmp = fPow2AddDiv2(tmp, spec); + } + bandEnergy[i] = tmp; + } + + for (i = 0; i < numBands; i++) { + INT scale = (2 * (sfbMaxScaleSpec[i] - 3)) - + 1; /* max sfbWidth = 36 ; 2^6=64 => 6/2 = 3 (spc*spc) */ + scale = fixMax(fixMin(scale, (DFRACT_BITS - 1)), -(DFRACT_BITS - 1)); + bandEnergy[i] = scaleValueSaturate(bandEnergy[i], -scale); + } +} + +/***************************************************************************** + functionname: FDKaacEnc_CalcBandNrgMSOpt + description: + input: + output: +*****************************************************************************/ +void FDKaacEnc_CalcBandNrgMSOpt( + const FIXP_DBL *RESTRICT mdctSpectrumLeft, + const FIXP_DBL *RESTRICT mdctSpectrumRight, + INT *RESTRICT sfbMaxScaleSpecLeft, INT *RESTRICT sfbMaxScaleSpecRight, + const INT *RESTRICT bandOffset, const INT numBands, + FIXP_DBL *RESTRICT bandEnergyMid, FIXP_DBL *RESTRICT bandEnergySide, + INT calcLdData, FIXP_DBL *RESTRICT bandEnergyMidLdData, + FIXP_DBL *RESTRICT bandEnergySideLdData) { + INT i, j, minScale; + FIXP_DBL NrgMid, NrgSide, specm, specs; + + for (i = 0; i < numBands; i++) { + NrgMid = NrgSide = FL2FXCONST_DBL(0.0); + minScale = fixMin(sfbMaxScaleSpecLeft[i], sfbMaxScaleSpecRight[i]) - 4; + minScale = fixMax(0, minScale); + + if (minScale > 0) { + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + FIXP_DBL specL = mdctSpectrumLeft[j] << (minScale - 1); + FIXP_DBL specR = mdctSpectrumRight[j] << (minScale - 1); + specm = specL + specR; + specs = specL - specR; + NrgMid = fPow2AddDiv2(NrgMid, specm); + NrgSide = fPow2AddDiv2(NrgSide, specs); + } + } else { + for (j = bandOffset[i]; j < bandOffset[i + 1]; j++) { + FIXP_DBL specL = mdctSpectrumLeft[j] >> 1; + FIXP_DBL specR = mdctSpectrumRight[j] >> 1; + specm = specL + specR; + specs = specL - specR; + NrgMid = fPow2AddDiv2(NrgMid, specm); + NrgSide = fPow2AddDiv2(NrgSide, specs); + } + } + bandEnergyMid[i] = fMin(NrgMid, (FIXP_DBL)MAXVAL_DBL >> 1) << 1; + bandEnergySide[i] = fMin(NrgSide, (FIXP_DBL)MAXVAL_DBL >> 1) << 1; + } + + if (calcLdData) { + LdDataVector(bandEnergyMid, bandEnergyMidLdData, numBands); + LdDataVector(bandEnergySide, bandEnergySideLdData, numBands); + } + + for (i = 0; i < numBands; i++) { + minScale = fixMin(sfbMaxScaleSpecLeft[i], sfbMaxScaleSpecRight[i]); + INT scale = fixMax(0, 2 * (minScale - 4)); + + if (calcLdData) { + /* using the minimal scaling of left and right channel can cause very + small energies; check ldNrg before subtract scaling multiplication: + fract*INT we don't need fMult */ + + int minus = scale * FL2FXCONST_DBL(1.0 / 64); + + if (bandEnergyMidLdData[i] != FL2FXCONST_DBL(-1.0f)) + bandEnergyMidLdData[i] -= minus; + + if (bandEnergySideLdData[i] != FL2FXCONST_DBL(-1.0f)) + bandEnergySideLdData[i] -= minus; + } + scale = fixMin(scale, (DFRACT_BITS - 1)); + bandEnergyMid[i] >>= scale; + bandEnergySide[i] >>= scale; + } +} |