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/***************************************************************************** 85 86 Description: FDKaacLdEnc_MdctTransform480: 87 The module FDKaacLdEnc_MdctTransform will perform the MDCT. 88 The MDCT supports the sine window and 89 the zero padded window. The algorithm of the MDCT 90 can be divided in Windowing, PreModulation, Fft and 91 PostModulation. 92 93******************************************************************************/ 94 95#include "transform.h" 96 97#include "dct.h" 98#include "psy_const.h" 99#include "aacEnc_rom.h" 100#include "FDK_tools_rom.h" 101 102INT FDKaacEnc_Transform_Real (const INT_PCM * pTimeData, 103 FIXP_DBL *RESTRICT mdctData, 104 const INT blockType, 105 const INT windowShape, 106 INT *prevWindowShape, 107 const INT frameLength, 108 INT *mdctData_e, 109 INT filterType 110 ,FIXP_DBL * RESTRICT overlapAddBuffer 111 ) 112{ 113 const INT_PCM * RESTRICT timeData; 114 115 INT i; 116 /* tl: transform length 117 fl: left window slope length 118 nl: left window slope offset 119 fr: right window slope length 120 nr: right window slope offset 121 See FDK_tools/doc/intern/mdct.tex for more detail. */ 122 int tl, fl, nl, fr, nr; 123 124 const FIXP_WTP * RESTRICT pLeftWindowPart; 125 const FIXP_WTP * RESTRICT pRightWindowPart; 126 127 /* 128 * MDCT scale: 129 * + 1: fMultDiv2() in windowing. 130 * + 1: Because of factor 1/2 in Princen-Bradley compliant windowed TDAC. 131 */ 132 *mdctData_e = 1+1; 133 134 tl = frameLength; 135 timeData = pTimeData; 136 137 switch( blockType ) { 138 case LONG_WINDOW: 139 { 140 int offset = (windowShape == LOL_WINDOW) ? ((frameLength * 3)>>2) : 0; 141 fl = frameLength - offset; 142 fr = frameLength - offset; 143 } 144 break; 145 case STOP_WINDOW: 146 fl = frameLength >> 3; 147 fr = frameLength; 148 break; 149 case START_WINDOW: /* or StopStartSequence */ 150 fl = frameLength; 151 fr = frameLength >> 3; 152 break; 153 case SHORT_WINDOW: 154 fl = fr = frameLength >> 3; 155 tl >>= 3; 156 timeData = pTimeData + 3*fl + (fl/2); 157 break; 158 default: 159 FDK_ASSERT(0); 160 return -1; 161 break; 162 } 163 164 /* Taken from FDK_tools/src/mdct.cpp Derive NR and NL */ 165 nr = (tl - fr)>>1; 166 nl = (tl - fl)>>1; 167 168 pLeftWindowPart = FDKgetWindowSlope(fl, *prevWindowShape); 169 pRightWindowPart = FDKgetWindowSlope(fr, windowShape); 170 171 /* windowing */ 172 if (filterType != FB_ELD) 173 { 174 /* Left window slope offset */ 175 for (i=0; i<nl ; i++) 176 { 177#if SAMPLE_BITS == DFRACT_BITS /* SPC_BITS and DFRACT_BITS should be equal. */ 178 mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] >> ( 1 ); 179#else 180 mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] << (DFRACT_BITS - SAMPLE_BITS - 1); 181#endif 182 } 183 /* Left window slope */ 184 for (i=0; i<fl/2; i++) 185 { 186 FIXP_DBL tmp0; 187 tmp0 = fMultDiv2((FIXP_PCM)timeData[i+nl], pLeftWindowPart[i].v.im); 188 mdctData[(tl/2)+i+nl] = fMultSubDiv2(tmp0, (FIXP_PCM)timeData[tl-nl-i-1], pLeftWindowPart[i].v.re); 189 } 190 191 /* Right window slope offset */ 192 for(i=0; i<nr; i++) 193 { 194#if SAMPLE_BITS == DFRACT_BITS /* This should be SPC_BITS instead of DFRACT_BITS. */ 195 mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] >> (1); 196#else 197 mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] << (DFRACT_BITS - SAMPLE_BITS - 1); 198#endif 199 } 200 /* Right window slope */ 201 for (i=0; i<fr/2; i++) 202 { 203 FIXP_DBL tmp1; 204 tmp1 = fMultDiv2((FIXP_PCM)timeData[tl+nr+i], pRightWindowPart[i].v.re); 205 mdctData[(tl/2)-nr-i-1] = -fMultAddDiv2(tmp1, (FIXP_PCM)timeData[(tl*2)-nr-i-1], pRightWindowPart[i].v.im); 206 } 207 } 208 209 if (filterType == FB_ELD) 210 { 211 const FIXP_WTB *pWindowELD=NULL; 212 int i, N = frameLength, L = frameLength; 213 214 if (frameLength == 512) { 215 pWindowELD = ELDAnalysis512; 216 } else { 217 pWindowELD = ELDAnalysis480; 218 } 219 220 for(i=0;i<N/4;i++) 221 { 222 FIXP_DBL z0, outval; 223 224 z0 = (fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i])<< (WTS0-1)) + (fMult((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N/2+i])<< (WTS0-1)); 225 226 outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1)); 227 outval += (fMultDiv2((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N+N/2+i]) >> (-WTS1) ); 228 outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i])>> (-WTS2-1)); 229 230 overlapAddBuffer[N/2+i] = overlapAddBuffer[i]; 231 232 overlapAddBuffer[i] = z0; 233 mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1)); 234 235 mdctData[N-1-i] = outval; 236 overlapAddBuffer[N+N/2-1-i] = outval; 237 } 238 239 for(i=N/4;i<N/2;i++) 240 { 241 FIXP_DBL z0, outval; 242 243 z0 = fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i]) << (WTS0-1); 244 245 outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1)) ; 246 outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i]) >> (-WTS2-1)); 247 248 overlapAddBuffer[N/2+i] = overlapAddBuffer[i] + (fMult((FIXP_PCM)timeData[L-N/4+i], pWindowELD[N/2+i])<< (WTS0-1) ); 249 250 overlapAddBuffer[i] = z0; 251 mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1)); 252 253 mdctData[N-1-i] = outval; 254 overlapAddBuffer[N+N/2-1-i] = outval; 255 } 256 } 257 258 dct_IV(mdctData, tl, mdctData_e); 259 260 *prevWindowShape = windowShape; 261 262 return 0; 263} 264 265