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 Filename: /audio/gsm_amr/c/src/reorder.c 31 32 ------------------------------------------------------------------------------ 33 REVISION HISTORY 34 35 Description: 36 1. Eliminated unused include file add.h. 37 2. Replaced array addressing by pointers 38 3. Eliminated math operations that unnecessary checked for 39 saturation 40 4. Replaced loop counter with decrement loops 41 42 Description: Replaced "int" and/or "char" with OSCL defined types. 43 44 Who: Date: 45 Description: 46 47 ------------------------------------------------------------------------------ 48 */ 49 50 51 /*---------------------------------------------------------------------------- 52 ; INCLUDES 53 ----------------------------------------------------------------------------*/ 54 #include "reorder.h" 55 56 /*---------------------------------------------------------------------------- 57 ; MACROS 58 ; [Define module specific macros here] 59 ----------------------------------------------------------------------------*/ 60 61 /*---------------------------------------------------------------------------- 62 ; DEFINES 63 ; [Include all pre-processor statements here. Include conditional 64 ; compile variables also.] 65 ----------------------------------------------------------------------------*/ 66 67 /*---------------------------------------------------------------------------- 68 ; LOCAL FUNCTION DEFINITIONS 69 ; [List function prototypes here] 70 ----------------------------------------------------------------------------*/ 71 72 /*---------------------------------------------------------------------------- 73 ; LOCAL VARIABLE DEFINITIONS 74 ; [Variable declaration - defined here and used outside this module] 75 ----------------------------------------------------------------------------*/ 76 77 78 /* 79 ------------------------------------------------------------------------------ 80 FUNCTION NAME: Reorder_lsf 81 ------------------------------------------------------------------------------ 82 INPUT AND OUTPUT DEFINITIONS 83 84 Inputs: 85 lsf = vector of LSFs (range: 0<=val<=0.5)(Word16) 86 min_dist = minimum required distance (Word16) 87 n = LPC order (Word16) 88 pOverflow = pointer to overflow (Flag) 89 90 Outputs: 91 pOverflow -> 1 if the add operation called by Reorder_lsf() results in 92 overflow 93 lsf -> reordered vector of LSFs (Word16) 94 95 Returns: 96 None 97 98 Global Variables Used: 99 None 100 101 Local Variables Needed: 102 None 103 104 ------------------------------------------------------------------------------ 105 FUNCTION DESCRIPTION 106 107 This function makes sure that the LSFs are properly ordered keeps a certain 108 minimum distance between adjacent LSFs. 109 110 ------------------------------------------------------------------------------ 111 REQUIREMENTS 112 113 None 114 115 ------------------------------------------------------------------------------ 116 REFERENCES 117 118 [1] reorder.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001 119 120 ------------------------------------------------------------------------------ 121 PSEUDO-CODE 122 123 void Reorder_lsf ( 124 Word16 *lsf, // (i/o) : vector of LSFs (range: 0<=val<=0.5) 125 Word16 min_dist, // (i) : minimum required distance 126 Word16 n // (i) : LPC order 127 ) 128 { 129 Word16 i; 130 Word16 lsf_min; 131 132 // The reference ETSI code uses a global flag for Overflow. In the actual 133 // implementation a pointer to Overflow flag is passed into the function 134 // for use by the math functions add() and sub() 135 136 lsf_min = min_dist; 137 for (i = 0; i < n; i++) 138 { 139 if (sub (lsf[i], lsf_min) < 0) 140 { 141 lsf[i] = lsf_min; 142 } 143 lsf_min = add (lsf[i], min_dist); 144 } 145 } 146 147 ------------------------------------------------------------------------------ 148 RESOURCES USED [optional] 149 150 When the code is written for a specific target processor the 151 the resources used should be documented below. 152 153 HEAP MEMORY USED: x bytes 154 155 STACK MEMORY USED: x bytes 156 157 CLOCK CYCLES: (cycle count equation for this function) + (variable 158 used to represent cycle count for each subroutine 159 called) 160 where: (cycle count variable) = cycle count for [subroutine 161 name] 162 163 ------------------------------------------------------------------------------ 164 CAUTION [optional] 165 [State any special notes, constraints or cautions for users of this function] 166 167 ------------------------------------------------------------------------------ 168 */ 169 170 /*---------------------------------------------------------------------------- 171 ; FUNCTION CODE 172 ----------------------------------------------------------------------------*/ 173 void Reorder_lsf( 174 Word16 *lsf, /* (i/o) : vector of LSFs (range: 0<=val<=0.5) */ 175 Word16 min_dist, /* (i) : minimum required distance */ 176 Word16 n, /* (i) : LPC order */ 177 Flag *pOverflow /* (i/o) : Overflow flag */ 178 ) 179 { 180 Word16 i; 181 Word16 lsf_min; 182 Word16 *p_lsf = &lsf[0]; 183 OSCL_UNUSED_ARG(pOverflow); 184 185 lsf_min = min_dist; 186 for (i = 0; i < n; i++) 187 { 188 if (*(p_lsf) < lsf_min) 189 { 190 *(p_lsf++) = lsf_min; 191 lsf_min += min_dist; 192 } 193 else 194 { 195 lsf_min = *(p_lsf++) + min_dist; 196 } 197 } 198 } 199 200
