1a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/* ------------------------------------------------------------------ 2a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * Copyright (C) 1998-2009 PacketVideo 3a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * 4a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * Licensed under the Apache License, Version 2.0 (the "License"); 5a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * you may not use this file except in compliance with the License. 6a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * You may obtain a copy of the License at 7a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * 8a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * http://www.apache.org/licenses/LICENSE-2.0 9a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * 10a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * Unless required by applicable law or agreed to in writing, software 11a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * distributed under the License is distributed on an "AS IS" BASIS, 12a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 13a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * express or implied. 14a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * See the License for the specific language governing permissions 15a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * and limitations under the License. 16a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber * ------------------------------------------------------------------- 17a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber */ 18a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/**************************************************************************************** 19a30d40083856cb4edd225faf8b488fab156e5976Andreas HuberPortions of this file are derived from the following 3GPP standard: 20a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 21a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 3GPP TS 26.073 22a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec 23a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Available from http://www.3gpp.org 24a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 25a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) 26a30d40083856cb4edd225faf8b488fab156e5976Andreas HuberPermission to distribute, modify and use this file under the standard license 27a30d40083856cb4edd225faf8b488fab156e5976Andreas Huberterms listed above has been obtained from the copyright holder. 28a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber****************************************************************************************/ 29a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/* 30a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 31a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 32a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 33a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 34a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Pathname: ./audio/gsm-amr/c/src/preemph.c 35a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Functions: 36a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 37a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Date: 02/04/2002 38a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 39a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 40a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber REVISION HISTORY 41a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 42a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description: Removed the functions preemphasis_init and preemphasis_exit. 43a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber The preemphasis related structure is no longer dynamically allocated. 44a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Placed file in the appropriate PV Software Template format. 45a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 46a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description: Changed to accept the pOverflow flag for EPOC compatibility. 47a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 48a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description: Replaced OSCL mem type functions and eliminated include 49a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber files that now are chosen by OSCL definitions 50a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 51a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description: Replaced "int" and/or "char" with OSCL defined types. 52a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 53a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description: 54a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 55a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 56a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber MODULE DESCRIPTION 57a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 58a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Purpose : Preemphasis filtering 59a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Description : Filtering through 1 - g z^-1 60a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 61a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 62a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber*/ 63a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 64a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/*---------------------------------------------------------------------------- 65a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; INCLUDES 66a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber----------------------------------------------------------------------------*/ 67a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber#include "preemph.h" 68a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber#include "typedef.h" 69a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber#include "basic_op.h" 70a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 71a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/*---------------------------------------------------------------------------- 72a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; MACROS 73a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; Define module specific macros here 74a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber----------------------------------------------------------------------------*/ 75a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 76a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/*---------------------------------------------------------------------------- 77a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; DEFINES 78a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; Include all pre-processor statements here. Include conditional 79a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; compile variables also. 80a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber----------------------------------------------------------------------------*/ 81a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 82a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/*---------------------------------------------------------------------------- 83a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; LOCAL FUNCTION DEFINITIONS 84a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; Function Prototype declaration 85a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber----------------------------------------------------------------------------*/ 86a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 87a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/*---------------------------------------------------------------------------- 88a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; LOCAL VARIABLE DEFINITIONS 89a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber; Variable declaration - defined here and used outside this module 90a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber----------------------------------------------------------------------------*/ 91a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 92a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 93a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/* 94a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 95a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber FUNCTION NAME: preemphasis_reset 96a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 97a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber INPUT AND OUTPUT DEFINITIONS 98a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 99a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Inputs: 100a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber st -- double pointer to preemphasisState 101a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 102a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Outputs: 103a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber st -- double ponter to preemphasisState 104a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 105a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Returns: 106a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber -1 if an error occurs 107a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 0 if OK 108a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 109a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Global Variables Used: 110a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 111a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 112a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Local Variables Needed: 113a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 114a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 115a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 116a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber FUNCTION DESCRIPTION 117a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 118a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Initializes state memory to zero 119a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 120a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber REQUIREMENTS 121a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 122a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 123a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 124a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 125a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber REFERENCES 126a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 127a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber preemph.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 128a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 129a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 130a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber PSEUDO-CODE 131a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 132a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 133a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 134a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber RESOURCES USED [optional] 135a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 136a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber When the code is written for a specific target processor the 137a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber the resources used should be documented below. 138a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 139a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber HEAP MEMORY USED: x bytes 140a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 141a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber STACK MEMORY USED: x bytes 142a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 143a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber CLOCK CYCLES: (cycle count equation for this function) + (variable 144a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber used to represent cycle count for each subroutine 145a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber called) 146a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber where: (cycle count variable) = cycle count for [subroutine 147a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber name] 148a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 149a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 150a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber CAUTION [optional] 151a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber [State any special notes, constraints or cautions for users of this function] 152a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 153a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 154a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber*/ 155a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 156a30d40083856cb4edd225faf8b488fab156e5976Andreas HuberWord16 preemphasis_reset(preemphasisState *state) 157a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber{ 158a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber if (state == (preemphasisState *) NULL) 159a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber { 160a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber /* fprintf(stderr, "preemphasis_reset: invalid parameter\n"); */ 161a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber return -1; 162a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber } 163a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 164a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber state->mem_pre = 0; 165a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 166a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber return 0; 167a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber} 168a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 169a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber/* 170a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 171a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber FUNCTION NAME: preemphasis 172a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 173a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber INPUT AND OUTPUT DEFINITIONS 174a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 175a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Inputs: 176a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber st -- Pointer to preemphasisState -- preemphasis filter state 177a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber signal -- array of type Word16 -- input signal overwritten by the output 178a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber g -- Word16 -- preemphasis coefficient 179a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber L -- Word16 -- size of filtering 180a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 181a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Outputs: 182a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber st -- Pointer to preemphasisState -- preemphasis filter state 183a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber signal -- array of type Word16 -- input signal overwritten by the output 184a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber pOverflow -- pointer to type Flag -- overflow indicator 185a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Returns: 186a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 187a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 188a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Global Variables Used: 189a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 190a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 191a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Local Variables Needed: 192a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 193a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 194a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 195a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber FUNCTION DESCRIPTION 196a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 197a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Filtering through 1 - g z^-1 198a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 199a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber REQUIREMENTS 200a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 201a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber None 202a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 203a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 204a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber REFERENCES 205a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 206a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber preemph.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 207a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 208a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 209a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber PSEUDO-CODE 210a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 211a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 212a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 213a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber RESOURCES USED [optional] 214a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 215a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber When the code is written for a specific target processor the 216a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber the resources used should be documented below. 217a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 218a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber HEAP MEMORY USED: x bytes 219a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 220a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber STACK MEMORY USED: x bytes 221a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 222a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber CLOCK CYCLES: (cycle count equation for this function) + (variable 223a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber used to represent cycle count for each subroutine 224a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber called) 225a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber where: (cycle count variable) = cycle count for [subroutine 226a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber name] 227a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 228a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 229a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber CAUTION [optional] 230a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber [State any special notes, constraints or cautions for users of this function] 231a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 232a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber------------------------------------------------------------------------------ 233a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber*/ 234a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 235a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 236a30d40083856cb4edd225faf8b488fab156e5976Andreas Hubervoid preemphasis( 237a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber preemphasisState *st, /* (i/o) : preemphasis filter state */ 238a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 *signal, /* (i/o) : input signal overwritten by the output */ 239a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 g, /* (i) : preemphasis coefficient */ 240a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 L, /* (i) : size of filtering */ 241a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Flag *pOverflow /* (o) : overflow indicator */ 242a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber) 243a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber{ 244a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 *p1; 245a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 *p2; 246a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 temp; 247a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 temp2; 248a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber Word16 i; 249a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 250a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber p1 = signal + L - 1; 251a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber p2 = p1 - 1; 252a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber temp = *p1; 253a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 254a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber for (i = 0; i <= L - 2; i++) 255a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber { 256a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber temp2 = mult(g, *(p2--), pOverflow); 257a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber *p1 = sub(*p1, temp2, pOverflow); 258a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 259a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber p1--; 260a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber } 261a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 262a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber temp2 = mult(g, st->mem_pre, pOverflow); 263a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 264a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber *p1 = sub(*p1, temp2, pOverflow); 265a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 266a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber st->mem_pre = temp; 267a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 268a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber return; 269a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber} 270a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 271a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 272a30d40083856cb4edd225faf8b488fab156e5976Andreas Huber 273