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/ex_ctrl.c 35 Funtions: ex_ctrl 36 37 Date: 02/08/2002 38 39 ------------------------------------------------------------------------------ 40 REVISION HISTORY 41 42 Description: Replaced "int" and/or "char" with OSCL defined types. 43 44 Description: 45 46 ------------------------------------------------------------------------------ 47 */ 48 49 /*---------------------------------------------------------------------------- 50 ; INCLUDES 51 ----------------------------------------------------------------------------*/ 52 #include "ex_ctrl.h" 53 #include "typedef.h" 54 #include "cnst.h" 55 #include "copy.h" 56 #include "set_zero.h" 57 #include "gmed_n.h" 58 #include "sqrt_l.h" 59 #include "basic_op.h" 60 /*---------------------------------------------------------------------------- 61 ; MACROS 62 ; Define module specific macros here 63 ----------------------------------------------------------------------------*/ 64 65 /*---------------------------------------------------------------------------- 66 ; DEFINES 67 ; Include all pre-processor statements here. Include conditional 68 ; compile variables also. 69 ----------------------------------------------------------------------------*/ 70 71 /*---------------------------------------------------------------------------- 72 ; LOCAL FUNCTION DEFINITIONS 73 ; Function Prototype declaration 74 ----------------------------------------------------------------------------*/ 75 76 /*---------------------------------------------------------------------------- 77 ; LOCAL VARIABLE DEFINITIONS 78 ; Variable declaration - defined here and used outside this module 79 ----------------------------------------------------------------------------*/ 80 81 /* 82 ------------------------------------------------------------------------------ 83 FUNCTION NAME: ex_ctrl 84 ------------------------------------------------------------------------------ 85 INPUT AND OUTPUT DEFINITIONS 86 87 Inputs: 88 excitation = pointer to current subframe excitation of type Word16 89 excEnergy = Exc. Energy, sqrt(totEx*totEx) of type Word16 90 exEnergyHist = pointer to history of subframe energies of type Word16 91 voicedHangover = # of fr. after last voiced fr of type Word16 92 carefulFlag = restrict dynamic in scaling of type Word16 93 pOverflow = pointer to overflow indicator 94 95 Outputs: 96 pOverflow = 1 if overflow exists in the math functions called by this function. 97 98 Returns: 99 None 100 101 Global Variables Used: 102 None 103 104 Local Variables Needed: 105 None 106 107 ------------------------------------------------------------------------------ 108 FUNCTION DESCRIPTION 109 110 Function : Ex_ctrl 111 Purpose : Charaterice synthesis speech and detect background noise 112 Returns : background noise decision; 0 = no bgn, 1 = bgn 113 114 ------------------------------------------------------------------------------ 115 REQUIREMENTS 116 117 None 118 119 ------------------------------------------------------------------------------ 120 REFERENCES 121 122 ex_ctrl.c, 3GPP TS 26.101 version 4.1.0 Release 4, June 2001 123 124 ------------------------------------------------------------------------------ 125 PSEUDO-CODE 126 127 128 129 ------------------------------------------------------------------------------ 130 RESOURCES USED [optional] 131 132 When the code is written for a specific target processor the 133 the resources used should be documented below. 134 135 HEAP MEMORY USED: x bytes 136 137 STACK MEMORY USED: x bytes 138 139 CLOCK CYCLES: (cycle count equation for this function) + (variable 140 used to represent cycle count for each subroutine 141 called) 142 where: (cycle count variable) = cycle count for [subroutine 143 name] 144 145 ------------------------------------------------------------------------------ 146 CAUTION [optional] 147 [State any special notes, constraints or cautions for users of this function] 148 149 ------------------------------------------------------------------------------ 150 */ 151 Word16 Ex_ctrl(Word16 excitation[], /*i/o: Current subframe excitation */ 152 Word16 excEnergy, /* i : Exc. Energy, sqrt(totEx*totEx)*/ 153 Word16 exEnergyHist[], /* i : History of subframe energies */ 154 Word16 voicedHangover, /* i : # of fr. after last voiced fr.*/ 155 Word16 prevBFI, /* i : Set i previous BFI */ 156 Word16 carefulFlag, /* i : Restrict dymamic in scaling */ 157 Flag *pOverflow 158 ) 159 { 160 Word16 i, exp; 161 Word16 testEnergy, scaleFactor, avgEnergy, prevEnergy; 162 Word32 t0; 163 164 /* get target level */ 165 avgEnergy = gmed_n(exEnergyHist, 9); 166 167 prevEnergy = shr(add(exEnergyHist[7], exEnergyHist[8], pOverflow) , 1, pOverflow); 168 169 if (exEnergyHist[8] < prevEnergy) 170 { 171 prevEnergy = exEnergyHist[8]; 172 } 173 174 /* upscaling to avoid too rapid energy rises for some cases */ 175 if ((excEnergy < avgEnergy) && (excEnergy > 5)) 176 { 177 testEnergy = shl(prevEnergy, 2, pOverflow); /* testEnergy = 4*prevEnergy; */ 178 179 if ((voicedHangover < 7) || prevBFI != 0) 180 { 181 /* testEnergy = 3*prevEnergy */ 182 testEnergy = sub(testEnergy, prevEnergy, pOverflow); 183 } 184 185 if (avgEnergy > testEnergy) 186 { 187 avgEnergy = testEnergy; 188 } 189 190 /* scaleFactor=avgEnergy/excEnergy in Q0 (const 29 below)*/ 191 exp = norm_s(excEnergy); 192 excEnergy = shl(excEnergy, exp, pOverflow); 193 excEnergy = div_s((Word16) 16383, excEnergy); 194 t0 = L_mult(avgEnergy, excEnergy, pOverflow); 195 t0 = L_shr(t0, sub(20, exp, pOverflow), pOverflow); 196 /* const=30 for t0 in Q0, 20 for Q10 */ 197 if (t0 > 32767) 198 { 199 t0 = 32767; /* saturate */ 200 } 201 scaleFactor = extract_l(t0); 202 203 /* test if scaleFactor > 3.0 */ 204 if (carefulFlag != 0 && (scaleFactor > 3072)) 205 { 206 scaleFactor = 3072; 207 } 208 209 /* scale the excitation by scaleFactor */ 210 for (i = 0; i < L_SUBFR; i++) 211 { 212 t0 = L_mult(scaleFactor, excitation[i], pOverflow); 213 t0 = L_shr(t0, 11, pOverflow); 214 excitation[i] = extract_l(t0); 215 } 216 } 217 218 return 0; 219 } 220
