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Diffstat (limited to 'libAACenc/src/line_pe.cpp')
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diff --git a/libAACenc/src/line_pe.cpp b/libAACenc/src/line_pe.cpp new file mode 100644 index 0000000..ed5ee7f --- /dev/null +++ b/libAACenc/src/line_pe.cpp @@ -0,0 +1,207 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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 Audio Encoder ************************** + + Initial author: M. Werner + contents/description: Perceptual entropie module + +******************************************************************************/ + +#include "line_pe.h" +#include "sf_estim.h" +#include "bit_cnt.h" + +#include "genericStds.h" + +static const FIXP_DBL C1LdData = FL2FXCONST_DBL(3.0/LD_DATA_SCALING); /* C1 = 3.0 = log(8.0)/log(2) */ +static const FIXP_DBL C2LdData = FL2FXCONST_DBL(1.3219281/LD_DATA_SCALING); /* C2 = 1.3219281 = log(2.5)/log(2) */ +static const FIXP_DBL C3LdData = FL2FXCONST_DBL(0.5593573); /* 1-C2/C1 */ + + +/* constants that do not change during successive pe calculations */ +void FDKaacEnc_prepareSfbPe(PE_CHANNEL_DATA *peChanData, + const FIXP_DBL *sfbEnergyLdData, + const FIXP_DBL *sfbThresholdLdData, + const FIXP_DBL *sfbFormFactorLdData, + const INT *sfbOffset, + const INT sfbCnt, + const INT sfbPerGroup, + const INT maxSfbPerGroup) +{ + INT sfbGrp,sfb; + INT sfbWidth; + FIXP_DBL avgFormFactorLdData; + const FIXP_DBL formFacScaling = FL2FXCONST_DBL((float)FORM_FAC_SHIFT/LD_DATA_SCALING); + + for (sfbGrp = 0;sfbGrp < sfbCnt;sfbGrp+=sfbPerGroup) { + for (sfb=0; sfb<maxSfbPerGroup; sfb++) { + if ((FIXP_DBL)sfbEnergyLdData[sfbGrp+sfb] > (FIXP_DBL)sfbThresholdLdData[sfbGrp+sfb]) { + sfbWidth = sfbOffset[sfbGrp+sfb+1] - sfbOffset[sfbGrp+sfb]; + /* estimate number of active lines */ + avgFormFactorLdData = ((-sfbEnergyLdData[sfbGrp+sfb]>>1) + (CalcLdInt(sfbWidth)>>1))>>1; + peChanData->sfbNLines[sfbGrp+sfb] = + (INT)CalcInvLdData( (sfbFormFactorLdData[sfbGrp+sfb] + formFacScaling) + avgFormFactorLdData); + } + else { + peChanData->sfbNLines[sfbGrp+sfb] = 0; + } + } + } +} + +/* + formula for one sfb: + pe = n * ld(en/thr), if ld(en/thr) >= C1 + pe = n * (C2 + C3 * ld(en/thr)), if ld(en/thr) < C1 + n: estimated number of lines in sfb, + ld(x) = log(x)/log(2) + + constPart is sfbPe without the threshold part n*ld(thr) or n*C3*ld(thr) +*/ +void FDKaacEnc_calcSfbPe(PE_CHANNEL_DATA *RESTRICT peChanData, + const FIXP_DBL *RESTRICT sfbEnergyLdData, + const FIXP_DBL *RESTRICT sfbThresholdLdData, + const INT sfbCnt, + const INT sfbPerGroup, + const INT maxSfbPerGroup, + const INT *isBook, + const INT *isScale) +{ + INT sfbGrp,sfb; + INT nLines; + FIXP_DBL logDataRatio; + INT lastValIs = 0; + + peChanData->pe = 0; + peChanData->constPart = 0; + peChanData->nActiveLines = 0; + + for(sfbGrp = 0;sfbGrp < sfbCnt;sfbGrp+=sfbPerGroup){ + for (sfb=0; sfb<maxSfbPerGroup; sfb++) { + if ((FIXP_DBL)sfbEnergyLdData[sfbGrp+sfb] > (FIXP_DBL)sfbThresholdLdData[sfbGrp+sfb]) { + logDataRatio = (FIXP_DBL)(sfbEnergyLdData[sfbGrp+sfb] - sfbThresholdLdData[sfbGrp+sfb]); + nLines = peChanData->sfbNLines[sfbGrp+sfb]; + if (logDataRatio >= C1LdData) { + /* scale sfbPe and sfbConstPart with PE_CONSTPART_SHIFT */ + peChanData->sfbPe[sfbGrp+sfb] = fMultDiv2(logDataRatio, (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); + peChanData->sfbConstPart[sfbGrp+sfb] = + fMultDiv2(sfbEnergyLdData[sfbGrp+sfb], (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); ; + + } + else { + /* scale sfbPe and sfbConstPart with PE_CONSTPART_SHIFT */ + peChanData->sfbPe[sfbGrp+sfb] = + fMultDiv2(((FIXP_DBL)C2LdData + fMult(C3LdData,logDataRatio)), (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); + + peChanData->sfbConstPart[sfbGrp+sfb] = + fMultDiv2(((FIXP_DBL)C2LdData + fMult(C3LdData,sfbEnergyLdData[sfbGrp+sfb])), + (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))) ; + + nLines = fMultI(C3LdData, nLines); + } + peChanData->sfbNActiveLines[sfbGrp+sfb] = nLines; + } + else if( isBook[sfb] ) { + /* provide for cost of scale factor for Intensity */ + INT delta = isScale[sfbGrp+sfb] - lastValIs; + lastValIs = isScale[sfbGrp+sfb]; + peChanData->sfbPe[sfbGrp+sfb] = FDKaacEnc_bitCountScalefactorDelta(delta)<<PE_CONSTPART_SHIFT; + peChanData->sfbConstPart[sfbGrp+sfb] = 0; + peChanData->sfbNActiveLines[sfbGrp+sfb] = 0; + } + else { + peChanData->sfbPe[sfbGrp+sfb] = 0; + peChanData->sfbConstPart[sfbGrp+sfb] = 0; + peChanData->sfbNActiveLines[sfbGrp+sfb] = 0; + } + /* sum up peChanData values */ + peChanData->pe += peChanData->sfbPe[sfbGrp+sfb]; + peChanData->constPart += peChanData->sfbConstPart[sfbGrp+sfb]; + peChanData->nActiveLines += peChanData->sfbNActiveLines[sfbGrp+sfb]; + } + } + /* correct scaled pe and constPart values */ + peChanData->pe>>=PE_CONSTPART_SHIFT; + peChanData->constPart>>=PE_CONSTPART_SHIFT; +} |