| /* ----------------------------------------------------------------------------- |
| 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: Quantization |
| |
| *******************************************************************************/ |
| |
| #include "quantize.h" |
| |
| #include "aacEnc_rom.h" |
| |
| /***************************************************************************** |
| |
| functionname: FDKaacEnc_quantizeLines |
| description: quantizes spectrum lines |
| returns: |
| input: global gain, number of lines to process, spectral data |
| output: quantized spectrum |
| |
| *****************************************************************************/ |
| static void FDKaacEnc_quantizeLines(INT gain, INT noOfLines, |
| const FIXP_DBL *mdctSpectrum, |
| SHORT *quaSpectrum, INT dZoneQuantEnable) { |
| int line; |
| FIXP_DBL k = FL2FXCONST_DBL(0.0f); |
| FIXP_QTD quantizer = FDKaacEnc_quantTableQ[(-gain) & 3]; |
| INT quantizershift = ((-gain) >> 2) + 1; |
| const INT kShift = 16; |
| |
| if (dZoneQuantEnable) |
| k = FL2FXCONST_DBL(0.23f) >> kShift; |
| else |
| k = FL2FXCONST_DBL(-0.0946f + 0.5f) >> kShift; |
| |
| for (line = 0; line < noOfLines; line++) { |
| FIXP_DBL accu = fMultDiv2(mdctSpectrum[line], quantizer); |
| |
| if (accu < FL2FXCONST_DBL(0.0f)) { |
| accu = -accu; |
| /* normalize */ |
| INT accuShift = CntLeadingZeros(accu) - 1; /* CountLeadingBits() is not |
| necessary here since test |
| value is always > 0 */ |
| accu <<= accuShift; |
| INT tabIndex = |
| (INT)(accu >> (DFRACT_BITS - 2 - MANT_DIGITS)) & (~MANT_SIZE); |
| INT totalShift = quantizershift - accuShift + 1; |
| accu = fMultDiv2(FDKaacEnc_mTab_3_4[tabIndex], |
| FDKaacEnc_quantTableE[totalShift & 3]); |
| totalShift = (16 - 4) - (3 * (totalShift >> 2)); |
| FDK_ASSERT(totalShift >= 0); /* MAX_QUANT_VIOLATION */ |
| accu >>= fixMin(totalShift, DFRACT_BITS - 1); |
| quaSpectrum[line] = |
| (SHORT)(-((LONG)(k + accu) >> (DFRACT_BITS - 1 - 16))); |
| } else if (accu > FL2FXCONST_DBL(0.0f)) { |
| /* normalize */ |
| INT accuShift = CntLeadingZeros(accu) - 1; /* CountLeadingBits() is not |
| necessary here since test |
| value is always > 0 */ |
| accu <<= accuShift; |
| INT tabIndex = |
| (INT)(accu >> (DFRACT_BITS - 2 - MANT_DIGITS)) & (~MANT_SIZE); |
| INT totalShift = quantizershift - accuShift + 1; |
| accu = fMultDiv2(FDKaacEnc_mTab_3_4[tabIndex], |
| FDKaacEnc_quantTableE[totalShift & 3]); |
| totalShift = (16 - 4) - (3 * (totalShift >> 2)); |
| FDK_ASSERT(totalShift >= 0); /* MAX_QUANT_VIOLATION */ |
| accu >>= fixMin(totalShift, DFRACT_BITS - 1); |
| quaSpectrum[line] = (SHORT)((LONG)(k + accu) >> (DFRACT_BITS - 1 - 16)); |
| } else { |
| quaSpectrum[line] = 0; |
| } |
| } |
| } |
| |
| /***************************************************************************** |
| |
| functionname:iFDKaacEnc_quantizeLines |
| description: iquantizes spectrum lines |
| mdctSpectrum = iquaSpectrum^4/3 *2^(0.25*gain) |
| input: global gain, number of lines to process,quantized spectrum |
| output: spectral data |
| |
| *****************************************************************************/ |
| static void FDKaacEnc_invQuantizeLines(INT gain, INT noOfLines, |
| SHORT *quantSpectrum, |
| FIXP_DBL *mdctSpectrum) |
| |
| { |
| INT iquantizermod; |
| INT iquantizershift; |
| INT line; |
| |
| iquantizermod = gain & 3; |
| iquantizershift = gain >> 2; |
| |
| for (line = 0; line < noOfLines; line++) { |
| if (quantSpectrum[line] < 0) { |
| FIXP_DBL accu; |
| INT ex, specExp, tabIndex; |
| FIXP_DBL s, t; |
| |
| accu = (FIXP_DBL)-quantSpectrum[line]; |
| |
| ex = CountLeadingBits(accu); |
| accu <<= ex; |
| specExp = (DFRACT_BITS - 1) - ex; |
| |
| FDK_ASSERT(specExp < 14); /* this fails if abs(value) > 8191 */ |
| |
| tabIndex = (INT)(accu >> (DFRACT_BITS - 2 - MANT_DIGITS)) & (~MANT_SIZE); |
| |
| /* calculate "mantissa" ^4/3 */ |
| s = FDKaacEnc_mTab_4_3Elc[tabIndex]; |
| |
| /* get approperiate exponent multiplier for specExp^3/4 combined with |
| * scfMod */ |
| t = FDKaacEnc_specExpMantTableCombElc[iquantizermod][specExp]; |
| |
| /* multiply "mantissa" ^4/3 with exponent multiplier */ |
| accu = fMult(s, t); |
| |
| /* get approperiate exponent shifter */ |
| specExp = FDKaacEnc_specExpTableComb[iquantizermod][specExp] - |
| 1; /* -1 to avoid overflows in accu */ |
| |
| if ((-iquantizershift - specExp) < 0) |
| accu <<= -(-iquantizershift - specExp); |
| else |
| accu >>= -iquantizershift - specExp; |
| |
| mdctSpectrum[line] = -accu; |
| } else if (quantSpectrum[line] > 0) { |
| FIXP_DBL accu; |
| INT ex, specExp, tabIndex; |
| FIXP_DBL s, t; |
| |
| accu = (FIXP_DBL)(INT)quantSpectrum[line]; |
| |
| ex = CountLeadingBits(accu); |
| accu <<= ex; |
| specExp = (DFRACT_BITS - 1) - ex; |
| |
| FDK_ASSERT(specExp < 14); /* this fails if abs(value) > 8191 */ |
| |
| tabIndex = (INT)(accu >> (DFRACT_BITS - 2 - MANT_DIGITS)) & (~MANT_SIZE); |
| |
| /* calculate "mantissa" ^4/3 */ |
| s = FDKaacEnc_mTab_4_3Elc[tabIndex]; |
| |
| /* get approperiate exponent multiplier for specExp^3/4 combined with |
| * scfMod */ |
| t = FDKaacEnc_specExpMantTableCombElc[iquantizermod][specExp]; |
| |
| /* multiply "mantissa" ^4/3 with exponent multiplier */ |
| accu = fMult(s, t); |
| |
| /* get approperiate exponent shifter */ |
| specExp = FDKaacEnc_specExpTableComb[iquantizermod][specExp] - |
| 1; /* -1 to avoid overflows in accu */ |
| |
| if ((-iquantizershift - specExp) < 0) |
| accu <<= -(-iquantizershift - specExp); |
| else |
| accu >>= -iquantizershift - specExp; |
| |
| mdctSpectrum[line] = accu; |
| } else { |
| mdctSpectrum[line] = FL2FXCONST_DBL(0.0f); |
| } |
| } |
| } |
| |
| /***************************************************************************** |
| |
| functionname: FDKaacEnc_QuantizeSpectrum |
| description: quantizes the entire spectrum |
| returns: |
| input: number of scalefactor bands to be quantized, ... |
| output: quantized spectrum |
| |
| *****************************************************************************/ |
| void FDKaacEnc_QuantizeSpectrum(INT sfbCnt, INT maxSfbPerGroup, INT sfbPerGroup, |
| const INT *sfbOffset, |
| const FIXP_DBL *mdctSpectrum, INT globalGain, |
| const INT *scalefactors, |
| SHORT *quantizedSpectrum, |
| INT dZoneQuantEnable) { |
| INT sfbOffs, sfb; |
| |
| /* in FDKaacEnc_quantizeLines quaSpectrum is calculated with: |
| spec^(3/4) * 2^(-3/16*QSS) * 2^(3/4*scale) + k |
| simplify scaling calculation and reduce QSS before: |
| spec^(3/4) * 2^(-3/16*(QSS - 4*scale)) */ |
| |
| for (sfbOffs = 0; sfbOffs < sfbCnt; sfbOffs += sfbPerGroup) |
| for (sfb = 0; sfb < maxSfbPerGroup; sfb++) { |
| INT scalefactor = scalefactors[sfbOffs + sfb]; |
| |
| FDKaacEnc_quantizeLines( |
| globalGain - scalefactor, /* QSS */ |
| sfbOffset[sfbOffs + sfb + 1] - sfbOffset[sfbOffs + sfb], |
| mdctSpectrum + sfbOffset[sfbOffs + sfb], |
| quantizedSpectrum + sfbOffset[sfbOffs + sfb], dZoneQuantEnable); |
| } |
| } |
| |
| /***************************************************************************** |
| |
| functionname: FDKaacEnc_calcSfbDist |
| description: calculates distortion of quantized values |
| returns: distortion |
| input: gain, number of lines to process, spectral data |
| output: |
| |
| *****************************************************************************/ |
| FIXP_DBL FDKaacEnc_calcSfbDist(const FIXP_DBL *mdctSpectrum, |
| SHORT *quantSpectrum, INT noOfLines, INT gain, |
| INT dZoneQuantEnable) { |
| INT i, scale; |
| FIXP_DBL xfsf; |
| FIXP_DBL diff; |
| FIXP_DBL invQuantSpec; |
| |
| xfsf = FL2FXCONST_DBL(0.0f); |
| |
| for (i = 0; i < noOfLines; i++) { |
| /* quantization */ |
| FDKaacEnc_quantizeLines(gain, 1, &mdctSpectrum[i], &quantSpectrum[i], |
| dZoneQuantEnable); |
| |
| if (fAbs(quantSpectrum[i]) > MAX_QUANT) { |
| return FL2FXCONST_DBL(0.0f); |
| } |
| /* inverse quantization */ |
| FDKaacEnc_invQuantizeLines(gain, 1, &quantSpectrum[i], &invQuantSpec); |
| |
| /* dist */ |
| diff = fixp_abs(fixp_abs(invQuantSpec) - fixp_abs(mdctSpectrum[i] >> 1)); |
| |
| scale = CountLeadingBits(diff); |
| diff = scaleValue(diff, scale); |
| diff = fPow2(diff); |
| scale = fixMin(2 * (scale - 1), DFRACT_BITS - 1); |
| |
| diff = scaleValue(diff, -scale); |
| |
| xfsf = xfsf + diff; |
| } |
| |
| xfsf = CalcLdData(xfsf); |
| |
| return xfsf; |
| } |
| |
| /***************************************************************************** |
| |
| functionname: FDKaacEnc_calcSfbQuantEnergyAndDist |
| description: calculates energy and distortion of quantized values |
| returns: |
| input: gain, number of lines to process, quantized spectral data, |
| spectral data |
| output: energy, distortion |
| |
| *****************************************************************************/ |
| void FDKaacEnc_calcSfbQuantEnergyAndDist(FIXP_DBL *mdctSpectrum, |
| SHORT *quantSpectrum, INT noOfLines, |
| INT gain, FIXP_DBL *en, |
| FIXP_DBL *dist) { |
| INT i, scale; |
| FIXP_DBL invQuantSpec; |
| FIXP_DBL diff; |
| |
| FIXP_DBL energy = FL2FXCONST_DBL(0.0f); |
| FIXP_DBL distortion = FL2FXCONST_DBL(0.0f); |
| |
| for (i = 0; i < noOfLines; i++) { |
| if (fAbs(quantSpectrum[i]) > MAX_QUANT) { |
| *en = FL2FXCONST_DBL(0.0f); |
| *dist = FL2FXCONST_DBL(0.0f); |
| return; |
| } |
| |
| /* inverse quantization */ |
| FDKaacEnc_invQuantizeLines(gain, 1, &quantSpectrum[i], &invQuantSpec); |
| |
| /* energy */ |
| energy += fPow2(invQuantSpec); |
| |
| /* dist */ |
| diff = fixp_abs(fixp_abs(invQuantSpec) - fixp_abs(mdctSpectrum[i] >> 1)); |
| |
| scale = CountLeadingBits(diff); |
| diff = scaleValue(diff, scale); |
| diff = fPow2(diff); |
| |
| scale = fixMin(2 * (scale - 1), DFRACT_BITS - 1); |
| |
| diff = scaleValue(diff, -scale); |
| |
| distortion += diff; |
| } |
| |
| *en = CalcLdData(energy) + FL2FXCONST_DBL(0.03125f); |
| *dist = CalcLdData(distortion); |
| } |
