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 Portions of this file are derived from the following 3GPP standard: 20 21 3GPP TS 26.073 22 ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec 23 Available from http://www.3gpp.org 24 25 (C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) 26 Permission to distribute, modify and use this file under the standard license 27 terms listed above has been obtained from the copyright holder. 28 ****************************************************************************************/ 29 /* 30 ------------------------------------------------------------------------------ 31 32 33 34 Pathname: ./audio/gsm-amr/c/src/d2_11pf.c 35 Functions: 36 37 Date: 01/28/2002 38 39 ------------------------------------------------------------------------------ 40 REVISION HISTORY 41 42 Description: Modified to place file in the correct template format. Eliminated 43 use of special functions to perform simple mathematical operations. 44 45 Description: Per review comments... 46 (1) Removed include of "count.h" and "basic_op.h" 47 48 Description: Replaced "int" and/or "char" with OSCL defined types. 49 50 Description: 51 52 ------------------------------------------------------------------------------ 53 MODULE DESCRIPTION 54 */ 55 56 /*---------------------------------------------------------------------------- 57 ; INCLUDES 58 ----------------------------------------------------------------------------*/ 59 #include "d2_11pf.h" 60 #include "typedef.h" 61 #include "cnst.h" 62 63 64 /*---------------------------------------------------------------------------- 65 ; MACROS 66 ; Define module specific macros here 67 ----------------------------------------------------------------------------*/ 68 69 /*---------------------------------------------------------------------------- 70 ; DEFINES 71 ; Include all pre-processor statements here. Include conditional 72 ; compile variables also. 73 ----------------------------------------------------------------------------*/ 74 #define NB_PULSE 2 75 76 77 /*---------------------------------------------------------------------------- 78 ; LOCAL FUNCTION DEFINITIONS 79 ; Function Prototype declaration 80 ----------------------------------------------------------------------------*/ 81 82 /*---------------------------------------------------------------------------- 83 ; LOCAL VARIABLE DEFINITIONS 84 ; Variable declaration - defined here and used outside this module 85 ----------------------------------------------------------------------------*/ 86 87 /* 88 ------------------------------------------------------------------------------ 89 FUNCTION NAME: decode_2i40_11bits 90 ------------------------------------------------------------------------------ 91 INPUT AND OUTPUT DEFINITIONS 92 93 Inputs: 94 sign -- Word16 -- signs of 2 pulses. 95 index -- Word16 -- Positions of the 2 pulses. 96 97 Outputs: 98 cod[] -- array of type Word16 -- algebraic (fixed) codebook excitation 99 100 Returns: 101 None 102 103 Global Variables Used: 104 None 105 106 Local Variables Needed: 107 None 108 109 ------------------------------------------------------------------------------ 110 FUNCTION DESCRIPTION 111 112 113 ------------------------------------------------------------------------------ 114 REQUIREMENTS 115 116 None 117 118 ------------------------------------------------------------------------------ 119 REFERENCES 120 121 d2_11pf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 122 123 ------------------------------------------------------------------------------ 124 PSEUDO-CODE 125 126 127 ------------------------------------------------------------------------------ 128 RESOURCES USED [optional] 129 130 When the code is written for a specific target processor the 131 the resources used should be documented below. 132 133 HEAP MEMORY USED: x bytes 134 135 STACK MEMORY USED: x bytes 136 137 CLOCK CYCLES: (cycle count equation for this function) + (variable 138 used to represent cycle count for each subroutine 139 called) 140 where: (cycle count variable) = cycle count for [subroutine 141 name] 142 143 ------------------------------------------------------------------------------ 144 CAUTION [optional] 145 [State any special notes, constraints or cautions for users of this function] 146 147 ------------------------------------------------------------------------------ 148 */ 149 150 void decode_2i40_11bits( 151 Word16 sign, /* i : signs of 2 pulses. */ 152 Word16 index, /* i : Positions of the 2 pulses. */ 153 Word16 cod[] /* o : algebraic (fixed) codebook excitation */ 154 ) 155 156 { 157 Word16 i; 158 Word16 j; 159 160 Word16 pos[NB_PULSE]; 161 162 /* Decode the positions */ 163 164 j = index & 0x1; 165 166 index >>= 1; 167 168 i = index & 0x7; 169 170 pos[0] = i * 5 + j * 2 + 1; 171 172 173 174 175 index >>= 3; 176 177 j = index & 0x3; 178 179 index >>= 2; 180 181 i = index & 0x7; 182 183 if (j == 3) 184 { 185 pos[1] = i * 5 + 4; 186 } 187 else 188 { 189 pos[1] = i * 5 + j; 190 } 191 192 193 194 195 /* decode the signs and build the codeword */ 196 for (i = 0; i < L_SUBFR; i++) 197 { 198 cod[i] = 0; 199 } 200 201 for (j = 0; j < NB_PULSE; j++) 202 { 203 i = sign & 1; 204 205 /* This line is equivalent to... 206 * 207 * 208 * if (i == 1) 209 * { 210 * cod[pos[j]] = 8191; 211 * } 212 * if (i == 0) 213 * { 214 * cod[pos[j]] = -8192; 215 * } 216 */ 217 218 cod[pos[j]] = i * 16383 - 8192; 219 220 sign >>= 1; 221 } 222 223 return; 224 } 225
