1 /* ------------------------------------------------------------------ 2 * Copyright (C) 1998-2009 PacketVideo 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 13 * express or implied. 14 * See the License for the specific language governing permissions 15 * and limitations under the License. 16 * ------------------------------------------------------------------- 17 */ 18 /* 19 20 Filename: sbr_find_start_andstop_band.c 21 22 ------------------------------------------------------------------------------ 23 REVISION HISTORY 24 25 26 Who: Date: MM/DD/YYYY 27 Description: 28 29 ------------------------------------------------------------------------------ 30 INPUT AND OUTPUT DEFINITIONS 31 32 33 34 ------------------------------------------------------------------------------ 35 FUNCTION DESCRIPTION 36 37 38 ------------------------------------------------------------------------------ 39 REQUIREMENTS 40 41 42 ------------------------------------------------------------------------------ 43 REFERENCES 44 45 SC 29 Software Copyright Licencing Disclaimer: 46 47 This software module was originally developed by 48 Coding Technologies 49 50 and edited by 51 - 52 53 in the course of development of the ISO/IEC 13818-7 and ISO/IEC 14496-3 54 standards for reference purposes and its performance may not have been 55 optimized. This software module is an implementation of one or more tools as 56 specified by the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards. 57 ISO/IEC gives users free license to this software module or modifications 58 thereof for use in products claiming conformance to audiovisual and 59 image-coding related ITU Recommendations and/or ISO/IEC International 60 Standards. ISO/IEC gives users the same free license to this software module or 61 modifications thereof for research purposes and further ISO/IEC standardisation. 62 Those intending to use this software module in products are advised that its 63 use may infringe existing patents. ISO/IEC have no liability for use of this 64 software module or modifications thereof. Copyright is not released for 65 products that do not conform to audiovisual and image-coding related ITU 66 Recommendations and/or ISO/IEC International Standards. 67 The original developer retains full right to modify and use the code for its 68 own purpose, assign or donate the code to a third party and to inhibit third 69 parties from using the code for products that do not conform to audiovisual and 70 image-coding related ITU Recommendations and/or ISO/IEC International Standards. 71 This copyright notice must be included in all copies or derivative works. 72 Copyright (c) ISO/IEC 2002. 73 74 ------------------------------------------------------------------------------ 75 PSEUDO-CODE 76 77 ------------------------------------------------------------------------------ 78 */ 79 80 81 /*---------------------------------------------------------------------------- 82 ; INCLUDES 83 ----------------------------------------------------------------------------*/ 84 85 #ifdef AAC_PLUS 86 87 88 #include "sbr_find_start_andstop_band.h" 89 #include "get_sbr_startfreq.h" 90 #include "get_sbr_stopfreq.h" 91 92 /*---------------------------------------------------------------------------- 93 ; MACROS 94 ; Define module specific macros here 95 ----------------------------------------------------------------------------*/ 96 97 98 /*---------------------------------------------------------------------------- 99 ; DEFINES 100 ; Include all pre-processor statements here. Include conditional 101 ; compile variables also. 102 ----------------------------------------------------------------------------*/ 103 104 /*---------------------------------------------------------------------------- 105 ; LOCAL FUNCTION DEFINITIONS 106 ; Function Prototype declaration 107 ----------------------------------------------------------------------------*/ 108 109 /*---------------------------------------------------------------------------- 110 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 111 ; Variable declaration - defined here and used outside this module 112 ----------------------------------------------------------------------------*/ 113 114 /*---------------------------------------------------------------------------- 115 ; EXTERNAL FUNCTION REFERENCES 116 ; Declare functions defined elsewhere and referenced in this module 117 ----------------------------------------------------------------------------*/ 118 119 /*---------------------------------------------------------------------------- 120 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 121 ; Declare variables used in this module but defined elsewhere 122 ----------------------------------------------------------------------------*/ 123 124 /*---------------------------------------------------------------------------- 125 ; FUNCTION CODE 126 ----------------------------------------------------------------------------*/ 127 128 SBR_ERROR sbr_find_start_andstop_band(const Int32 samplingFreq, 129 const Int32 startFreq, 130 const Int32 stopFreq, 131 Int *lsbM, 132 Int *usb) 133 { 134 /* Update startFreq struct */ 135 *lsbM = get_sbr_startfreq(samplingFreq, startFreq); 136 137 if (*lsbM == 0) 138 { 139 return(SBRDEC_ILLEGAL_SCFACTORS); 140 } 141 142 /*Update stopFreq struct */ 143 if (stopFreq < 13) 144 { 145 *usb = get_sbr_stopfreq(samplingFreq, stopFreq); 146 } 147 else if (stopFreq == 13) 148 { 149 *usb = 64; 150 } 151 else if (stopFreq == 14) 152 { 153 *usb = (*lsbM) << 1; 154 } 155 else 156 { 157 *usb = 3 * *lsbM; 158 } 159 160 /* limit to Nyqvist */ 161 if (*usb > 64) 162 { 163 *usb = 64; 164 } 165 166 /* test for invalid lsb, usb combinations */ 167 if ((*usb - *lsbM) > 48) 168 { 169 /* 170 * invalid SBR bitstream ? 171 */ 172 return(SBRDEC_INVALID_BITSTREAM); 173 } 174 175 if ((samplingFreq == 44100) && ((*usb - *lsbM) > 35)) 176 { 177 /* 178 * invalid SBR bitstream ? 179 */ 180 return(SBRDEC_INVALID_BITSTREAM); 181 } 182 183 if ((samplingFreq >= 48000) && ((*usb - *lsbM) > 32)) 184 { 185 /* 186 * invalid SBR bitstream ? 187 */ 188 return(SBRDEC_INVALID_BITSTREAM); 189 } 190 191 return(SBRDEC_OK); 192 193 } 194 195 #endif 196 197 198 199
