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/convolve.c 35 36 Date: 06/19/2000 37 38 ------------------------------------------------------------------------------ 39 REVISION HISTORY 40 41 Description: Optimize for speed. Update to code template. 42 43 Description: Added author name and date, fixed tabs, and added missing 44 sections. Updated Input/Output section. 45 46 Description: Optimized code by calculating two convolution sums per iteration 47 of the outer loop, thereby, decreasing outer loop count by 2. 48 Updated input/output definitions to be the same as the assembly 49 file (convolve.asm). Left Pseudo-code section blank. 50 51 Description: Deleted semi-colon in the Pointers modified section. 52 53 Description: Synchronized file with UMTS version 3.2.0. Updated coding 54 template. Removed unnecessary include files. 55 56 Description: Made the following changes per comments from Phase 2/3 review: 57 1. Fixed typecasting issue with TI C compiler. 58 2. Modified FOR loop to count down, wherever applicable. 59 60 Description: Made the following changes 61 1. Unrolled the correlation loop. 62 2. Performed 2 correlation per pass per sample to avoid recalling 63 the same data twice. 64 3. Eliminated math operations that check for saturation. 65 66 Description: 67 1. Modified loop counter, extra unrolling did speed up code 68 69 Description: Replaced "int" and/or "char" with OSCL defined types. 70 71 Description: Using inlines from fxp_arithmetic.h . 72 73 Description: Replacing fxp_arithmetic.h with basic_op.h. 74 75 Description: 76 77 ------------------------------------------------------------------------------ 78 */ 79 80 /*---------------------------------------------------------------------------- 81 ; INCLUDES 82 ----------------------------------------------------------------------------*/ 83 #include "typedef.h" 84 #include "convolve.h" 85 #include "basic_op.h" 86 87 /*---------------------------------------------------------------------------- 88 ; MACROS 89 ; Define module specific macros here 90 ----------------------------------------------------------------------------*/ 91 92 93 /*---------------------------------------------------------------------------- 94 ; DEFINES 95 ; Include all pre-processor statements here. Include conditional 96 ; compile variables also. 97 ----------------------------------------------------------------------------*/ 98 99 100 /*---------------------------------------------------------------------------- 101 ; LOCAL FUNCTION DEFINITIONS 102 ; Function Prototype declaration 103 ----------------------------------------------------------------------------*/ 104 105 /*---------------------------------------------------------------------------- 106 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 107 ; Variable declaration - defined here and used outside this module 108 ----------------------------------------------------------------------------*/ 109 110 111 /* 112 ------------------------------------------------------------------------------ 113 FUNCTION NAME: Convolve 114 ------------------------------------------------------------------------------ 115 INPUT AND OUTPUT DEFINITIONS 116 117 Inputs: 118 x = pointer to input vector of L elements of type Word16 119 h = pointer to the filter's impulse response vector of L elements 120 of type Word16 121 y = pointer to the output vector of L elements of type Word16 used for 122 storing the convolution of x and h; 123 L = Length of the convolution; type definition is Word16 124 125 Outputs: 126 y buffer contains the new convolution output 127 128 Returns: 129 None 130 131 Global Variables Used: 132 None 133 134 Local Variables Needed: 135 None 136 137 ------------------------------------------------------------------------------ 138 FUNCTION DESCRIPTION 139 140 Perform the convolution between two vectors x[] and h[] and write the result 141 in the vector y[]. All vectors are of length L and only the first L samples 142 of the convolution are computed. 143 144 The convolution is given by: 145 146 y[n] = sum_{i=0}^{n} x[i] h[n-i], n=0,...,L-1 147 148 ------------------------------------------------------------------------------ 149 REQUIREMENTS 150 151 None 152 153 ------------------------------------------------------------------------------ 154 REFERENCES 155 156 convolve.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 157 158 ------------------------------------------------------------------------------ 159 PSEUDO-CODE 160 161 void Convolve ( 162 Word16 x[], // (i) : input vector 163 Word16 h[], // (i) : impulse response 164 Word16 y[], // (o) : output vector 165 Word16 L // (i) : vector size 166 ) 167 { 168 Word16 i, n; 169 Word32 s; 170 171 for (n = 0; n < L; n++) 172 { 173 s = 0; move32 (); 174 for (i = 0; i <= n; i++) 175 { 176 s = L_mac (s, x[i], h[n - i]); 177 } 178 s = L_shl (s, 3); 179 y[n] = extract_h (s); move16 (); 180 } 181 182 return; 183 } 184 185 ------------------------------------------------------------------------------ 186 RESOURCES USED [optional] 187 188 When the code is written for a specific target processor the 189 the resources used should be documented below. 190 191 HEAP MEMORY USED: x bytes 192 193 STACK MEMORY USED: x bytes 194 195 CLOCK CYCLES: (cycle count equation for this function) + (variable 196 used to represent cycle count for each subroutine 197 called) 198 where: (cycle count variable) = cycle count for [subroutine 199 name] 200 201 ------------------------------------------------------------------------------ 202 CAUTION [optional] 203 [State any special notes, constraints or cautions for users of this function] 204 205 ------------------------------------------------------------------------------ 206 */ 207 208 void Convolve( 209 Word16 x[], /* (i) : input vector */ 210 Word16 h[], /* (i) : impulse response */ 211 Word16 y[], /* (o) : output vector */ 212 Word16 L /* (i) : vector size */ 213 ) 214 { 215 register Word16 i, n; 216 Word32 s1, s2; 217 218 219 for (n = 1; n < L; n = n + 2) 220 { 221 222 h = h + n; 223 224 s2 = ((Word32) * (x)) * *(h--); 225 s1 = ((Word32) * (x++)) * *(h); 226 227 for (i = (n - 1) >> 1; i != 0; i--) 228 { 229 s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h--), s2); 230 s1 = amrnb_fxp_mac_16_by_16bb((Word32) * (x++), (Word32) * (h), s1); 231 s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h--), s2); 232 s1 = amrnb_fxp_mac_16_by_16bb((Word32) * (x++), (Word32) * (h), s1); 233 } 234 235 s2 = amrnb_fxp_mac_16_by_16bb((Word32) * (x), (Word32) * (h), s2); 236 237 *(y++) = (Word16)(s1 >> 12); 238 *(y++) = (Word16)(s2 >> 12); 239 240 x = x - n; 241 242 } 243 244 return; 245 } 246
