| /* ----------------------------------------------------------------------------- |
| 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; |
| } |
| } |
