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/int_lsf.c 35 36 Date: 04/20/2000 37 38 ------------------------------------------------------------------------------ 39 REVISION HISTORY 40 41 Description: Put file into template and first pass at optimization. 42 43 Description: Made changes based on comments from the review meeting. Used 44 pointers instead of index addressing in the arrays. 45 46 Description: Added type definition to the input/output section. Fixed tabs. 47 Deleted pseudo-code. 48 49 Description: Synchronized file with UMTS versin 3.2.0. Updated coding 50 template. Removed unnecessary include files. 51 52 Description: Made the following changes per comments from Phase 2/3 review: 53 1. Modified FOR loops to count down. 54 2. Made some cosmetic changes in the Pseudo-code section. 55 56 Description: Changed to pass in overflow flag pointer to the add() routine. 57 58 Description: Replaced "int" and/or "char" with OSCL defined types. 59 60 Description: 61 62 ------------------------------------------------------------------------------ 63 */ 64 65 /*---------------------------------------------------------------------------- 66 ; INCLUDES 67 ----------------------------------------------------------------------------*/ 68 #include "int_lsf.h" 69 #include "typedef.h" 70 #include "basic_op.h" 71 #include "cnst.h" 72 73 /*---------------------------------------------------------------------------- 74 ; MACROS 75 ; Define module specific macros here 76 ----------------------------------------------------------------------------*/ 77 78 79 /*---------------------------------------------------------------------------- 80 ; DEFINES 81 ; Include all pre-processor statements here. Include conditional 82 ; compile variables also. 83 ----------------------------------------------------------------------------*/ 84 85 86 /*---------------------------------------------------------------------------- 87 ; LOCAL FUNCTION DEFINITIONS 88 ; Function Prototype declaration 89 ----------------------------------------------------------------------------*/ 90 91 92 /*---------------------------------------------------------------------------- 93 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 94 ; Variable declaration - defined here and used outside this module 95 ----------------------------------------------------------------------------*/ 96 97 98 /* 99 ------------------------------------------------------------------------------ 100 FUNCTION NAME: Int_lsf 101 ------------------------------------------------------------------------------ 102 INPUT AND OUTPUT DEFINITIONS 103 104 Inputs: 105 lsf_old = LSF vector at the 4th SF of past frame (Word16) 106 lsf_new = LSF vector at the 4th SF of present frame (Word16) 107 i_subfr = Current subframe (equal to 0,40,80 or 120) (Word16) 108 lsf_out = interpolated LSF parameters for current subframe (Word16) 109 110 Outputs: 111 lsf_out = new interpolated LSF parameters for current subframe 112 pOverflow = pointer of type Flag * to overflow indicator. 113 114 Returns: 115 None. 116 117 Global Variables Used: 118 None. 119 120 Local Variables Needed: 121 None. 122 123 ------------------------------------------------------------------------------ 124 FUNCTION DESCRIPTION 125 126 This function interpolates the LSFs for selected subframe. 127 The 20 ms speech frame is divided into 4 subframes. The LSFs are 128 interpolated at the 1st, 2nd and 3rd subframe and only forwarded 129 at the 4th subframe. 130 131 |------|------|------|------| 132 sf1 sf2 sf3 sf4 133 F0 F1 134 135 sf1: 3/4 F0 + 1/4 F1 sf3: 1/4 F0 + 3/4 F1 136 sf2: 1/2 F0 + 1/2 F1 sf4: F1 137 138 ------------------------------------------------------------------------------ 139 REQUIREMENTS 140 141 None. 142 143 ------------------------------------------------------------------------------ 144 REFERENCES 145 146 int_lsf.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 147 148 ------------------------------------------------------------------------------ 149 PSEUDO-CODE 150 151 void Int_lsf( 152 Word16 lsf_old[], // i : LSF vector at the 4th SF of past frame 153 Word16 lsf_new[], // i : LSF vector at the 4th SF of present frame 154 Word16 i_subfr, // i : Pointer to current sf (equal to 0,40,80 or 120) 155 Word16 lsf_out[] // o : interpolated LSF parameters for current sf 156 ) 157 { 158 Word16 i; 159 160 if ( i_subfr == 0 ) 161 { 162 for (i = 0; i < M; i++) { 163 lsf_out[i] = add(sub(lsf_old[i], shr(lsf_old[i], 2)), 164 shr(lsf_new[i], 2)); 165 } 166 } 167 else if ( sub(i_subfr, 40) == 0 ) 168 { 169 for (i = 0; i < M; i++) { 170 lsf_out[i] = add(shr(lsf_old[i],1), shr(lsf_new[i], 1) ); 171 } 172 } 173 else if ( sub(i_subfr, 80) == 0 ) 174 { 175 for (i = 0; i < M; i++) { 176 lsf_out[i] = add(shr(lsf_old[i], 2), 177 sub(lsf_new[i], shr(lsf_new[i], 2))); 178 } 179 } 180 else if ( sub(i_subfr, 120) == 0 ) 181 { 182 for (i = 0; i < M; i++) { 183 lsf_out[i] = lsf_new[i]; 184 } 185 } 186 187 return; 188 } 189 190 ------------------------------------------------------------------------------ 191 RESOURCES USED [optional] 192 193 When the code is written for a specific target processor the 194 the resources used should be documented below. 195 196 HEAP MEMORY USED: x bytes 197 198 STACK MEMORY USED: x bytes 199 200 CLOCK CYCLES: (cycle count equation for this function) + (variable 201 used to represent cycle count for each subroutine 202 called) 203 where: (cycle count variable) = cycle count for [subroutine 204 name] 205 206 ------------------------------------------------------------------------------ 207 CAUTION [optional] 208 [State any special notes, constraints or cautions for users of this function] 209 210 ------------------------------------------------------------------------------ 211 */ 212 213 void Int_lsf( 214 Word16 lsf_old[], /* i : LSF vector at the 4th SF of past frame */ 215 Word16 lsf_new[], /* i : LSF vector at the 4th SF of present frame */ 216 Word16 i_subfr, /* i : Current sf (equal to 0,40,80 or 120) */ 217 Word16 lsf_out[], /* o : interpolated LSF parameters for current sf */ 218 Flag *pOverflow /* o : flag set if overflow occurs */ 219 ) 220 { 221 register Word16 i; 222 register Word16 temp1; 223 register Word16 temp2; 224 225 if (i_subfr == 0) 226 { 227 for (i = M - 1; i >= 0; i--) 228 { 229 if (*(lsf_old + i) < 0) 230 { 231 temp1 = ~(~(*(lsf_old + i)) >> 2); 232 } 233 else 234 { 235 temp1 = *(lsf_old + i) >> 2; 236 } 237 if (*(lsf_new + i) < 0) 238 { 239 temp2 = ~(~(*(lsf_new + i)) >> 2); 240 } 241 else 242 { 243 temp2 = *(lsf_new + i) >> 2; 244 } 245 *(lsf_out + i) = add((Word16)(*(lsf_old + i) - temp1), 246 (Word16)temp2, 247 pOverflow); 248 } 249 } 250 251 else if (i_subfr == 40) 252 { 253 for (i = M - 1; i >= 0; i--) 254 { 255 if (*(lsf_old + i) < 0) 256 { 257 temp1 = ~(~(*(lsf_old + i)) >> 1); 258 } 259 else 260 { 261 temp1 = *(lsf_old + i) >> 1; 262 } 263 if (*(lsf_new + i) < 0) 264 { 265 temp2 = ~(~(*(lsf_new + i)) >> 1); 266 } 267 else 268 { 269 temp2 = *(lsf_new + i) >> 1; 270 } 271 *(lsf_out + i) = add( 272 temp1, 273 temp2, 274 pOverflow); 275 } 276 } 277 278 else if (i_subfr == 80) 279 { 280 for (i = M - 1; i >= 0; i--) 281 { 282 if (*(lsf_old + i) < 0) 283 { 284 temp1 = ~(~(*(lsf_old + i)) >> 2); 285 } 286 else 287 { 288 temp1 = *(lsf_old + i) >> 2; 289 } 290 if (*(lsf_new + i) < 0) 291 { 292 temp2 = ~(~(*(lsf_new + i)) >> 2); 293 } 294 else 295 { 296 temp2 = *(lsf_new + i) >> 2; 297 } 298 *(lsf_out + i) = add((Word16)temp1, 299 (Word16)(*(lsf_new + i) - temp2), 300 pOverflow); 301 302 } 303 } 304 305 else if (i_subfr == 120) 306 { 307 for (i = M - 1; i >= 0; i--) 308 { 309 *(lsf_out + i) = *(lsf_new + i); 310 } 311 } 312 313 return; 314 } 315 316
