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Diffstat (limited to 'fdk-aac/libAACenc/src/quantize.cpp')
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diff --git a/fdk-aac/libAACenc/src/quantize.cpp b/fdk-aac/libAACenc/src/quantize.cpp new file mode 100644 index 0000000..4d25263 --- /dev/null +++ b/fdk-aac/libAACenc/src/quantize.cpp @@ -0,0 +1,401 @@ +/* ----------------------------------------------------------------------------- +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); +} |