1 2/* ----------------------------------------------------------------------------------------------------------- 3Software License for The Fraunhofer FDK AAC Codec Library for Android 4 5� Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V. 6 All rights reserved. 7 8 1. INTRODUCTION 9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements 10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio. 11This FDK AAC Codec software is intended to be used on a wide variety of Android devices. 12 13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual 14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by 15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part 16of the MPEG specifications. 17 18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer) 19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners 20individually for the purpose of encoding or decoding bit streams in products that are compliant with 21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license 22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec 23software may already be covered under those patent licenses when it is used for those licensed purposes only. 24 25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality, 26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional 27applications information and documentation. 28 292. COPYRIGHT LICENSE 30 31Redistribution and use in source and binary forms, with or without modification, are permitted without 32payment of copyright license fees provided that you satisfy the following conditions: 33 34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or 35your modifications thereto in source code form. 36 37You must retain the complete text of this software license in the documentation and/or other materials 38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form. 39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your 40modifications thereto to recipients of copies in binary form. 41 42The name of Fraunhofer may not be used to endorse or promote products derived from this library without 43prior written permission. 44 45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec 46software or your modifications thereto. 47 48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software 49and the date of any change. For modified versions of the FDK AAC Codec, the term 50"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term 51"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android." 52 533. NO PATENT LICENSE 54 55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer, 56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with 57respect to this software. 58 59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized 60by appropriate patent licenses. 61 624. DISCLAIMER 63 64This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors 65"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties 66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages, 68including but not limited to procurement of substitute goods or services; loss of use, data, or profits, 69or business interruption, however caused and on any theory of liability, whether in contract, strict 70liability, or tort (including negligence), arising in any way out of the use of this software, even if 71advised of the possibility of such damage. 72 735. CONTACT INFORMATION 74 75Fraunhofer Institute for Integrated Circuits IIS 76Attention: Audio and Multimedia Departments - FDK AAC LL 77Am Wolfsmantel 33 7891058 Erlangen, Germany 79 80www.iis.fraunhofer.de/amm 81amm-info@iis.fraunhofer.de 82----------------------------------------------------------------------------------------------------------- */ 83 84/******************************** MPEG Audio Encoder ************************** 85 86 Initial author: M. Werner 87 contents/description: Perceptual entropie module 88 89******************************************************************************/ 90 91#include "line_pe.h" 92#include "sf_estim.h" 93#include "bit_cnt.h" 94 95#include "genericStds.h" 96 97static const FIXP_DBL C1LdData = FL2FXCONST_DBL(3.0/LD_DATA_SCALING); /* C1 = 3.0 = log(8.0)/log(2) */ 98static const FIXP_DBL C2LdData = FL2FXCONST_DBL(1.3219281/LD_DATA_SCALING); /* C2 = 1.3219281 = log(2.5)/log(2) */ 99static const FIXP_DBL C3LdData = FL2FXCONST_DBL(0.5593573); /* 1-C2/C1 */ 100 101 102/* constants that do not change during successive pe calculations */ 103void FDKaacEnc_prepareSfbPe(PE_CHANNEL_DATA *peChanData, 104 const FIXP_DBL *sfbEnergyLdData, 105 const FIXP_DBL *sfbThresholdLdData, 106 const FIXP_DBL *sfbFormFactorLdData, 107 const INT *sfbOffset, 108 const INT sfbCnt, 109 const INT sfbPerGroup, 110 const INT maxSfbPerGroup) 111{ 112 INT sfbGrp,sfb; 113 INT sfbWidth; 114 FIXP_DBL avgFormFactorLdData; 115 const FIXP_DBL formFacScaling = FL2FXCONST_DBL((float)FORM_FAC_SHIFT/LD_DATA_SCALING); 116 117 for (sfbGrp = 0;sfbGrp < sfbCnt;sfbGrp+=sfbPerGroup) { 118 for (sfb=0; sfb<maxSfbPerGroup; sfb++) { 119 if ((FIXP_DBL)sfbEnergyLdData[sfbGrp+sfb] > (FIXP_DBL)sfbThresholdLdData[sfbGrp+sfb]) { 120 sfbWidth = sfbOffset[sfbGrp+sfb+1] - sfbOffset[sfbGrp+sfb]; 121 /* estimate number of active lines */ 122 avgFormFactorLdData = ((-sfbEnergyLdData[sfbGrp+sfb]>>1) + (CalcLdInt(sfbWidth)>>1))>>1; 123 peChanData->sfbNLines[sfbGrp+sfb] = 124 (INT)CalcInvLdData( (sfbFormFactorLdData[sfbGrp+sfb] + formFacScaling) + avgFormFactorLdData); 125 /* Make sure sfbNLines is never greater than sfbWidth due to unaccuracies (e.g. sfbEnergyLdData[sfbGrp+sfb] = 0x80000000) */ 126 peChanData->sfbNLines[sfbGrp+sfb] = fMin(sfbWidth, peChanData->sfbNLines[sfbGrp+sfb]); 127 } 128 else { 129 peChanData->sfbNLines[sfbGrp+sfb] = 0; 130 } 131 } 132 } 133} 134 135/* 136 formula for one sfb: 137 pe = n * ld(en/thr), if ld(en/thr) >= C1 138 pe = n * (C2 + C3 * ld(en/thr)), if ld(en/thr) < C1 139 n: estimated number of lines in sfb, 140 ld(x) = log(x)/log(2) 141 142 constPart is sfbPe without the threshold part n*ld(thr) or n*C3*ld(thr) 143*/ 144void FDKaacEnc_calcSfbPe(PE_CHANNEL_DATA *RESTRICT peChanData, 145 const FIXP_DBL *RESTRICT sfbEnergyLdData, 146 const FIXP_DBL *RESTRICT sfbThresholdLdData, 147 const INT sfbCnt, 148 const INT sfbPerGroup, 149 const INT maxSfbPerGroup, 150 const INT *isBook, 151 const INT *isScale) 152{ 153 INT sfbGrp,sfb; 154 INT nLines; 155 FIXP_DBL logDataRatio; 156 INT lastValIs = 0; 157 158 peChanData->pe = 0; 159 peChanData->constPart = 0; 160 peChanData->nActiveLines = 0; 161 162 for(sfbGrp = 0;sfbGrp < sfbCnt;sfbGrp+=sfbPerGroup){ 163 for (sfb=0; sfb<maxSfbPerGroup; sfb++) { 164 if ((FIXP_DBL)sfbEnergyLdData[sfbGrp+sfb] > (FIXP_DBL)sfbThresholdLdData[sfbGrp+sfb]) { 165 logDataRatio = (FIXP_DBL)(sfbEnergyLdData[sfbGrp+sfb] - sfbThresholdLdData[sfbGrp+sfb]); 166 nLines = peChanData->sfbNLines[sfbGrp+sfb]; 167 if (logDataRatio >= C1LdData) { 168 /* scale sfbPe and sfbConstPart with PE_CONSTPART_SHIFT */ 169 peChanData->sfbPe[sfbGrp+sfb] = fMultDiv2(logDataRatio, (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); 170 peChanData->sfbConstPart[sfbGrp+sfb] = 171 fMultDiv2(sfbEnergyLdData[sfbGrp+sfb], (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); ; 172 173 } 174 else { 175 /* scale sfbPe and sfbConstPart with PE_CONSTPART_SHIFT */ 176 peChanData->sfbPe[sfbGrp+sfb] = 177 fMultDiv2(((FIXP_DBL)C2LdData + fMult(C3LdData,logDataRatio)), (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))); 178 179 peChanData->sfbConstPart[sfbGrp+sfb] = 180 fMultDiv2(((FIXP_DBL)C2LdData + fMult(C3LdData,sfbEnergyLdData[sfbGrp+sfb])), 181 (FIXP_DBL)(nLines<<(LD_DATA_SHIFT+PE_CONSTPART_SHIFT+1))) ; 182 183 nLines = fMultI(C3LdData, nLines); 184 } 185 peChanData->sfbNActiveLines[sfbGrp+sfb] = nLines; 186 } 187 else if( isBook[sfbGrp+sfb] ) { 188 /* provide for cost of scale factor for Intensity */ 189 INT delta = isScale[sfbGrp+sfb] - lastValIs; 190 lastValIs = isScale[sfbGrp+sfb]; 191 peChanData->sfbPe[sfbGrp+sfb] = FDKaacEnc_bitCountScalefactorDelta(delta)<<PE_CONSTPART_SHIFT; 192 peChanData->sfbConstPart[sfbGrp+sfb] = 0; 193 peChanData->sfbNActiveLines[sfbGrp+sfb] = 0; 194 } 195 else { 196 peChanData->sfbPe[sfbGrp+sfb] = 0; 197 peChanData->sfbConstPart[sfbGrp+sfb] = 0; 198 peChanData->sfbNActiveLines[sfbGrp+sfb] = 0; 199 } 200 /* sum up peChanData values */ 201 peChanData->pe += peChanData->sfbPe[sfbGrp+sfb]; 202 peChanData->constPart += peChanData->sfbConstPart[sfbGrp+sfb]; 203 peChanData->nActiveLines += peChanData->sfbNActiveLines[sfbGrp+sfb]; 204 } 205 } 206 /* correct scaled pe and constPart values */ 207 peChanData->pe>>=PE_CONSTPART_SHIFT; 208 peChanData->constPart>>=PE_CONSTPART_SHIFT; 209} 210