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 Pathname: ./audio/gsm-amr/c/src/residu.c 32 33 ------------------------------------------------------------------------------ 34 REVISION HISTORY 35 36 Description: Updated template used to PV coding template. First attempt at 37 optimizing code. 38 39 Description: Deleted stores listed in the Local Stores Needed/Modified 40 section. 41 42 Description: Updated file per comments gathered from Phase 2/3 review. 43 44 Description: Updating to reflect variable name changes made in residu.asm 45 46 Description: Synchronized file with UMTS version 3.2.0. Updated coding 47 template. Removed unnecessary include files. 48 49 Description: Made the following changes per comments from Phase 2/3 review: 50 1. Modified FOR loops to count down. 51 2. Fixed typecasting issue with TI C compiler. 52 53 Description: Made the following changes 54 1. Unrolled the convolutional loop. 55 2. Performed 4 convolution per pass to avoid recalling the same 56 filter coefficient as many times. 57 2. Eliminated math operations that check for saturation. 58 59 Description: Replaced "int" and/or "char" with OSCL defined types. 60 61 Description: Changed round function name to pv_round to avoid conflict with 62 round function in C standard library. 63 64 Who: Date: 65 Description: 66 67 ------------------------------------------------------------------------------ 68 */ 69 70 /*---------------------------------------------------------------------------- 71 ; INCLUDES 72 ----------------------------------------------------------------------------*/ 73 #include "residu.h" 74 #include "typedef.h" 75 #include "cnst.h" 76 77 /*---------------------------------------------------------------------------- 78 ; MACROS 79 ; Define module specific macros here 80 ----------------------------------------------------------------------------*/ 81 82 /*---------------------------------------------------------------------------- 83 ; DEFINES 84 ; Include all pre-processor statements here. Include conditional 85 ; compile variables also. 86 ----------------------------------------------------------------------------*/ 87 88 /*---------------------------------------------------------------------------- 89 ; LOCAL FUNCTION DEFINITIONS 90 ; Function Prototype declaration 91 ----------------------------------------------------------------------------*/ 92 93 /*---------------------------------------------------------------------------- 94 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 95 ; Variable declaration - defined here and used outside this module 96 ----------------------------------------------------------------------------*/ 97 98 99 /* 100 ------------------------------------------------------------------------------ 101 FUNCTION NAME: Residu 102 ------------------------------------------------------------------------------ 103 INPUT AND OUTPUT DEFINITIONS 104 105 Inputs: 106 coef_ptr = pointer to buffer containing the prediction coefficients 107 input_ptr = pointer to buffer containing the speech signal 108 input_len = filter order 109 residual_ptr = pointer to buffer of residual signal 110 111 Outputs: 112 residual_ptr buffer contains the newly calculated the residual signal 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 computes the LP residual by filtering the input speech through 127 the LP inverse filter A(z). 128 129 ------------------------------------------------------------------------------ 130 REQUIREMENTS 131 132 None 133 134 ------------------------------------------------------------------------------ 135 REFERENCES 136 137 residu.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 138 139 ------------------------------------------------------------------------------ 140 PSEUDO-CODE 141 142 Note: Input argument names were changed to be more descriptive. Shown below 143 are the original names. Shown below are the name changes: 144 a[] <--> coef_ptr[] 145 x[] <--> input_ptr[] 146 y[] <--> residual_ptr[] 147 lg <--> input_len 148 149 150 void Residu ( 151 Word16 a[], // (i) : prediction coefficients 152 Word16 x[], // (i) : speech signal 153 Word16 y[], // (o) : residual signal 154 Word16 lg // (i) : size of filtering 155 ) 156 { 157 Word16 i, j; 158 Word32 s; 159 160 for (i = 0; i < lg; i++) 161 { 162 s = L_mult (x[i], a[0]); 163 for (j = 1; j <= M; j++) 164 { 165 s = L_mac (s, a[j], x[i - j]); 166 } 167 s = L_shl (s, 3); 168 y[i] = pv_round (s); 169 } 170 return; 171 } 172 173 ------------------------------------------------------------------------------ 174 RESOURCES USED [optional] 175 176 When the code is written for a specific target processor the 177 the resources used should be documented below. 178 179 HEAP MEMORY USED: x bytes 180 181 STACK MEMORY USED: x bytes 182 183 CLOCK CYCLES: (cycle count equation for this function) + (variable 184 used to represent cycle count for each subroutine 185 called) 186 where: (cycle count variable) = cycle count for [subroutine 187 name] 188 189 ------------------------------------------------------------------------------ 190 CAUTION [optional] 191 [State any special notes, constraints or cautions for users of this function] 192 193 ------------------------------------------------------------------------------ 194 */ 195 196 void Residu( 197 Word16 coef_ptr[], /* (i) : prediction coefficients*/ 198 Word16 input_ptr[], /* (i) : speech signal */ 199 Word16 residual_ptr[], /* (o) : residual signal */ 200 Word16 input_len /* (i) : size of filtering */ 201 ) 202 { 203 204 205 Word16 i, j; 206 Word32 s1; 207 Word32 s2; 208 Word32 s3; 209 Word32 s4; 210 Word16 *p_input1; 211 Word16 *p_input2; 212 Word16 *p_input3; 213 Word16 *p_input4; 214 Word16 *p_coef; 215 Word16 *p_residual_ptr = &residual_ptr[input_len-1]; 216 Word16 *p_input_ptr = &input_ptr[input_len-1-M]; 217 218 for (i = input_len >> 2; i != 0; i--) 219 { 220 s1 = 0x0000800L; 221 s2 = 0x0000800L; 222 s3 = 0x0000800L; 223 s4 = 0x0000800L; 224 p_coef = &coef_ptr[M]; 225 p_input1 = p_input_ptr--; 226 p_input2 = p_input_ptr--; 227 p_input3 = p_input_ptr--; 228 p_input4 = p_input_ptr--; 229 230 for (j = M >> 1; j != 0; j--) 231 { 232 s1 += ((Word32) * (p_coef) * *(p_input1++)); 233 s2 += ((Word32) * (p_coef) * *(p_input2++)); 234 s3 += ((Word32) * (p_coef) * *(p_input3++)); 235 s4 += ((Word32) * (p_coef--) * *(p_input4++)); 236 s1 += ((Word32) * (p_coef) * *(p_input1++)); 237 s2 += ((Word32) * (p_coef) * *(p_input2++)); 238 s3 += ((Word32) * (p_coef) * *(p_input3++)); 239 s4 += ((Word32) * (p_coef--) * *(p_input4++)); 240 } 241 242 s1 += (((Word32) * (p_coef)) * *(p_input1)); 243 s2 += (((Word32) * (p_coef)) * *(p_input2)); 244 s3 += (((Word32) * (p_coef)) * *(p_input3)); 245 s4 += (((Word32) * (p_coef)) * *(p_input4)); 246 247 *(p_residual_ptr--) = (Word16)(s1 >> 12); 248 *(p_residual_ptr--) = (Word16)(s2 >> 12); 249 *(p_residual_ptr--) = (Word16)(s3 >> 12); 250 *(p_residual_ptr--) = (Word16)(s4 >> 12); 251 252 } 253 254 return; 255 } 256
