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_extract_extended_data.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 SBR_FRAME_DATA *hFrameData, Destination for extracted data of left channel 33 SBR_FRAME_DATA *hFrameDataRight Destination for extracted data of right channel 34 BIT_BUFFER hBitBuf pointer to bit buffer 35 36 37 ------------------------------------------------------------------------------ 38 FUNCTION DESCRIPTION 39 40 Reads extension data from the bitstream 41 42 The bitstream format allows up to 4 kinds of extended data element. 43 Extended data may contain several elements, each identified by a 2-bit-ID. 44 45 ------------------------------------------------------------------------------ 46 REQUIREMENTS 47 48 49 ------------------------------------------------------------------------------ 50 REFERENCES 51 52 SC 29 Software Copyright Licencing Disclaimer: 53 54 This software module was originally developed by 55 Coding Technologies 56 57 and edited by 58 - 59 60 in the course of development of the ISO/IEC 13818-7 and ISO/IEC 14496-3 61 standards for reference purposes and its performance may not have been 62 optimized. This software module is an implementation of one or more tools as 63 specified by the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards. 64 ISO/IEC gives users free license to this software module or modifications 65 thereof for use in products claiming conformance to audiovisual and 66 image-coding related ITU Recommendations and/or ISO/IEC International 67 Standards. ISO/IEC gives users the same free license to this software module or 68 modifications thereof for research purposes and further ISO/IEC standardisation. 69 Those intending to use this software module in products are advised that its 70 use may infringe existing patents. ISO/IEC have no liability for use of this 71 software module or modifications thereof. Copyright is not released for 72 products that do not conform to audiovisual and image-coding related ITU 73 Recommendations and/or ISO/IEC International Standards. 74 The original developer retains full right to modify and use the code for its 75 own purpose, assign or donate the code to a third party and to inhibit third 76 parties from using the code for products that do not conform to audiovisual and 77 image-coding related ITU Recommendations and/or ISO/IEC International Standards. 78 This copyright notice must be included in all copies or derivative works. 79 Copyright (c) ISO/IEC 2002. 80 81 ------------------------------------------------------------------------------ 82 PSEUDO-CODE 83 84 ------------------------------------------------------------------------------ 85 */ 86 87 88 /*---------------------------------------------------------------------------- 89 ; INCLUDES 90 ----------------------------------------------------------------------------*/ 91 92 #ifdef AAC_PLUS 93 94 95 #include "sbr_extract_extended_data.h" 96 #include "buf_getbits.h" 97 98 #ifdef PARAMETRICSTEREO 99 #include "ps_read_data.h" 100 #endif 101 102 /*---------------------------------------------------------------------------- 103 ; MACROS 104 ; Define module specific macros here 105 ----------------------------------------------------------------------------*/ 106 107 108 /*---------------------------------------------------------------------------- 109 ; DEFINES 110 ; Include all pre-processor statements here. Include conditional 111 ; compile variables also. 112 ----------------------------------------------------------------------------*/ 113 114 /*---------------------------------------------------------------------------- 115 ; LOCAL FUNCTION DEFINITIONS 116 ; Function Prototype declaration 117 ----------------------------------------------------------------------------*/ 118 119 /*---------------------------------------------------------------------------- 120 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 121 ; Variable declaration - defined here and used outside this module 122 ----------------------------------------------------------------------------*/ 123 124 /*---------------------------------------------------------------------------- 125 ; EXTERNAL FUNCTION REFERENCES 126 ; Declare functions defined elsewhere and referenced in this module 127 ----------------------------------------------------------------------------*/ 128 129 /*---------------------------------------------------------------------------- 130 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 131 ; Declare variables used in this module but defined elsewhere 132 ----------------------------------------------------------------------------*/ 133 134 /*---------------------------------------------------------------------------- 135 ; FUNCTION CODE 136 ----------------------------------------------------------------------------*/ 137 138 void sbr_extract_extended_data(BIT_BUFFER * hBitBuf 139 #ifdef PARAMETRICSTEREO /* Parametric Stereo Decoder */ 140 , HANDLE_PS_DEC hParametricStereoDec 141 #endif 142 ) 143 { 144 Int32 extended_data; 145 Int32 i; 146 Int32 nBitsLeft; 147 Int32 extension_id; 148 149 extended_data = buf_get_1bit(hBitBuf); /* SI_SBR_EXTENDED_DATA_BITS */ 150 151 if (extended_data) 152 { 153 Int32 cnt; 154 155 cnt = buf_getbits(hBitBuf, SI_SBR_EXTENSION_SIZE_BITS); 156 if (cnt == (1 << SI_SBR_EXTENSION_SIZE_BITS) - 1) 157 { 158 cnt += buf_getbits(hBitBuf, SI_SBR_EXTENSION_ESC_COUNT_BITS); 159 } 160 161 nBitsLeft = (cnt << 3); 162 while (nBitsLeft > 7) 163 { 164 extension_id = buf_getbits(hBitBuf, SI_SBR_EXTENSION_ID_BITS); 165 nBitsLeft -= SI_SBR_EXTENSION_ID_BITS; 166 167 switch (extension_id) 168 { 169 #ifdef HQ_SBR 170 #ifdef PARAMETRICSTEREO 171 172 /* 173 * Parametric Coding supports the Transient, Sinusoidal, Noise, and 174 * Parametric Stereo tools (MPEG4). 175 * 3GPP use aac+ hq along with ps for enhanced aac+ 176 * The PS tool uses complex-value QMF data, therefore can not be used 177 * with low power version of aac+ 178 */ 179 case EXTENSION_ID_PS_CODING: 180 181 if (hParametricStereoDec != NULL) 182 { 183 if (!hParametricStereoDec->psDetected) 184 { 185 /* parametric stereo detected */ 186 hParametricStereoDec->psDetected = 1; 187 } 188 189 nBitsLeft -= ps_read_data(hParametricStereoDec, 190 hBitBuf, 191 nBitsLeft); 192 193 } 194 195 break; 196 #endif 197 #endif 198 case 0: 199 200 default: 201 /* An unknown extension id causes the remaining extension data 202 * to be skipped 203 */ 204 cnt = nBitsLeft >> 3; /* number of remaining bytes */ 205 206 for (i = 0; i < cnt; i++) 207 { 208 buf_getbits(hBitBuf, 8); 209 } 210 211 nBitsLeft -= (cnt << 3); 212 } 213 } 214 /* read fill bits for byte alignment */ 215 buf_getbits(hBitBuf, nBitsLeft); 216 } 217 } 218 219 220 #endif 221 222 223 224
