1 /* ----------------------------------------------------------------------------- 2 Software License for The Fraunhofer FDK AAC Codec Library for Android 3 4 Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Frderung der angewandten 5 Forschung e.V. All rights reserved. 6 7 1. INTRODUCTION 8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software 9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding 10 scheme for digital audio. This FDK AAC Codec software is intended to be used on 11 a wide variety of Android devices. 12 13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient 14 general perceptual audio codecs. AAC-ELD is considered the best-performing 15 full-bandwidth communications codec by independent studies and is widely 16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG 17 specifications. 18 19 Patent licenses for necessary patent claims for the FDK AAC Codec (including 20 those of Fraunhofer) may be obtained through Via Licensing 21 (www.vialicensing.com) or through the respective patent owners individually for 22 the purpose of encoding or decoding bit streams in products that are compliant 23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of 24 Android devices already license these patent claims through Via Licensing or 25 directly from the patent owners, and therefore FDK AAC Codec software may 26 already be covered under those patent licenses when it is used for those 27 licensed purposes only. 28 29 Commercially-licensed AAC software libraries, including floating-point versions 30 with enhanced sound quality, are also available from Fraunhofer. Users are 31 encouraged to check the Fraunhofer website for additional applications 32 information and documentation. 33 34 2. COPYRIGHT LICENSE 35 36 Redistribution and use in source and binary forms, with or without modification, 37 are permitted without payment of copyright license fees provided that you 38 satisfy the following conditions: 39 40 You must retain the complete text of this software license in redistributions of 41 the FDK AAC Codec or your modifications thereto in source code form. 42 43 You must retain the complete text of this software license in the documentation 44 and/or other materials provided with redistributions of the FDK AAC Codec or 45 your modifications thereto in binary form. You must make available free of 46 charge copies of the complete source code of the FDK AAC Codec and your 47 modifications thereto to recipients of copies in binary form. 48 49 The name of Fraunhofer may not be used to endorse or promote products derived 50 from this library without prior written permission. 51 52 You may not charge copyright license fees for anyone to use, copy or distribute 53 the FDK AAC Codec software or your modifications thereto. 54 55 Your modified versions of the FDK AAC Codec must carry prominent notices stating 56 that you changed the software and the date of any change. For modified versions 57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android" 58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK 59 AAC Codec Library for Android." 60 61 3. NO PATENT LICENSE 62 63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without 64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE. 65 Fraunhofer provides no warranty of patent non-infringement with respect to this 66 software. 67 68 You may use this FDK AAC Codec software or modifications thereto only for 69 purposes that are authorized by appropriate patent licenses. 70 71 4. DISCLAIMER 72 73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright 74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, 75 including but not limited to the implied warranties of merchantability and 76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, 78 or consequential damages, including but not limited to procurement of substitute 79 goods or services; loss of use, data, or profits, or business interruption, 80 however caused and on any theory of liability, whether in contract, strict 81 liability, or tort (including negligence), arising in any way out of the use of 82 this software, even if advised of the possibility of such damage. 83 84 5. CONTACT INFORMATION 85 86 Fraunhofer Institute for Integrated Circuits IIS 87 Attention: Audio and Multimedia Departments - FDK AAC LL 88 Am Wolfsmantel 33 89 91058 Erlangen, Germany 90 91 www.iis.fraunhofer.de/amm 92 amm-info (at) iis.fraunhofer.de 93 ----------------------------------------------------------------------------- */ 94 95 /**************************** AAC encoder library ****************************** 96 97 Author(s): M. Werner 98 99 Description: Chaos measure calculation 100 101 *******************************************************************************/ 102 103 #include "chaosmeasure.h" 104 105 /***************************************************************************** 106 functionname: FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast 107 description: Eberlein method of chaos measure calculation by high-pass 108 filtering amplitude spectrum 109 A special case of FDKaacEnc_CalculateChaosMeasureTonalGeneric 110 -- highly optimized 111 *****************************************************************************/ 112 static void FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( 113 FIXP_DBL *RESTRICT paMDCTDataNM0, INT numberOfLines, 114 FIXP_DBL *RESTRICT chaosMeasure) { 115 INT i, j; 116 117 /* calculate chaos measure by "peak filter" */ 118 /* make even and odd pass through data */ 119 FIXP_DBL left_0_div2, 120 center_0; /* left, center tap of filter, even numbered */ 121 FIXP_DBL left_1_div2, center_1; /* left, center tap of filter, odd numbered */ 122 123 left_0_div2 = (FIXP_DBL)(((LONG)paMDCTDataNM0[0] ^ 124 ((LONG)paMDCTDataNM0[0] >> (DFRACT_BITS - 1))) >> 125 1); 126 left_1_div2 = (FIXP_DBL)(((LONG)paMDCTDataNM0[1] ^ 127 ((LONG)paMDCTDataNM0[1] >> (DFRACT_BITS - 1))) >> 128 1); 129 center_0 = (FIXP_DBL)((LONG)paMDCTDataNM0[2] ^ 130 ((LONG)paMDCTDataNM0[2] >> (DFRACT_BITS - 1))); 131 center_1 = (FIXP_DBL)((LONG)paMDCTDataNM0[3] ^ 132 ((LONG)paMDCTDataNM0[3] >> (DFRACT_BITS - 1))); 133 134 for (j = 2; j < numberOfLines - 2; j += 2) { 135 FIXP_DBL right_0 = 136 (FIXP_DBL)((LONG)paMDCTDataNM0[j + 2] ^ 137 ((LONG)paMDCTDataNM0[j + 2] >> (DFRACT_BITS - 1))); 138 FIXP_DBL tmp_0 = left_0_div2 + (right_0 >> 1); 139 FIXP_DBL right_1 = 140 (FIXP_DBL)((LONG)paMDCTDataNM0[j + 3] ^ 141 ((LONG)paMDCTDataNM0[j + 3] >> (DFRACT_BITS - 1))); 142 FIXP_DBL tmp_1 = left_1_div2 + (right_1 >> 1); 143 144 if (tmp_0 < center_0) { 145 INT leadingBits = CntLeadingZeros(center_0) - 1; 146 tmp_0 = schur_div(tmp_0 << leadingBits, center_0 << leadingBits, 8); 147 tmp_0 = fMult(tmp_0, tmp_0); 148 } else { 149 tmp_0 = (FIXP_DBL)MAXVAL_DBL; 150 } 151 chaosMeasure[j + 0] = tmp_0; 152 left_0_div2 = center_0 >> 1; 153 center_0 = right_0; 154 155 if (tmp_1 < center_1) { 156 INT leadingBits = CntLeadingZeros(center_1) - 1; 157 tmp_1 = schur_div(tmp_1 << leadingBits, center_1 << leadingBits, 8); 158 tmp_1 = fMult(tmp_1, tmp_1); 159 } else { 160 tmp_1 = (FIXP_DBL)MAXVAL_DBL; 161 } 162 163 left_1_div2 = center_1 >> 1; 164 center_1 = right_1; 165 chaosMeasure[j + 1] = tmp_1; 166 } 167 168 /* provide chaos measure for first few lines */ 169 chaosMeasure[0] = chaosMeasure[2]; 170 chaosMeasure[1] = chaosMeasure[2]; 171 172 /* provide chaos measure for last few lines */ 173 for (i = (numberOfLines - 3); i < numberOfLines; i++) 174 chaosMeasure[i] = FL2FXCONST_DBL(0.5); 175 } 176 177 /***************************************************************************** 178 functionname: FDKaacEnc_CalculateChaosMeasure 179 description: calculates a chaosmeasure for every line, different methods 180 are available. 0 means tonal, 1 means noiselike 181 returns: 182 input: MDCT data, number of lines 183 output: chaosMeasure 184 *****************************************************************************/ 185 void FDKaacEnc_CalculateChaosMeasure(FIXP_DBL *paMDCTDataNM0, INT numberOfLines, 186 FIXP_DBL *chaosMeasure) 187 188 { 189 FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( 190 paMDCTDataNM0, numberOfLines, chaosMeasure); 191 } 192
