median5.cpp revision 4f1efc098cb5791c3e9f483f2af84aef70d2d0a0
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/**************************************************************************************** 19Portions of this file are derived from the following 3GPP standard: 20 21 3GPP TS 26.173 22 ANSI-C code for the Adaptive Multi-Rate - Wideband (AMR-WB) speech codec 23 Available from http://www.3gpp.org 24 25(C) 2007, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) 26Permission to distribute, modify and use this file under the standard license 27terms listed above has been obtained from the copyright holder. 28****************************************************************************************/ 29/* 30------------------------------------------------------------------------------ 31 32 33 34 Filename: median5.cpp 35 36 Date: 05/08/2007 37 38------------------------------------------------------------------------------ 39 REVISION HISTORY 40 41 42 Description: 43 44------------------------------------------------------------------------------ 45 INPUT AND OUTPUT DEFINITIONS 46 47 INPUT 48 X[-2:2] 16-bit integers. 49 50 RETURN VALUE 51 The median of {X[-2], X[-1],..., X[2]}. 52 53------------------------------------------------------------------------------ 54 FUNCTION DESCRIPTION 55 56 Returns the median of the set {X[-2], X[-1],..., X[2]}, 57 whose elements are 16-bit integers. 58 59------------------------------------------------------------------------------ 60 REQUIREMENTS 61 62 63------------------------------------------------------------------------------ 64 REFERENCES 65 66------------------------------------------------------------------------------ 67 PSEUDO-CODE 68 69------------------------------------------------------------------------------ 70*/ 71 72 73/*---------------------------------------------------------------------------- 74; INCLUDES 75----------------------------------------------------------------------------*/ 76 77#include "pv_amr_wb_type_defs.h" 78#include "pvamrwbdecoder_basic_op.h" 79#include "pvamrwbdecoder_acelp.h" 80#include "pvamrwb_math_op.h" 81 82/*---------------------------------------------------------------------------- 83; MACROS 84; Define module specific macros here 85----------------------------------------------------------------------------*/ 86 87 88/*---------------------------------------------------------------------------- 89; DEFINES 90; Include all pre-processor statements here. Include conditional 91; compile variables also. 92----------------------------------------------------------------------------*/ 93 94/*---------------------------------------------------------------------------- 95; LOCAL FUNCTION DEFINITIONS 96; Function Prototype declaration 97----------------------------------------------------------------------------*/ 98 99/*---------------------------------------------------------------------------- 100; LOCAL STORE/BUFFER/POINTER DEFINITIONS 101; Variable declaration - defined here and used outside this module 102----------------------------------------------------------------------------*/ 103 104/*---------------------------------------------------------------------------- 105; EXTERNAL FUNCTION REFERENCES 106; Declare functions defined elsewhere and referenced in this module 107----------------------------------------------------------------------------*/ 108 109/*---------------------------------------------------------------------------- 110; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 111; Declare variables used in this module but defined elsewhere 112----------------------------------------------------------------------------*/ 113 114/*---------------------------------------------------------------------------- 115; FUNCTION CODE 116----------------------------------------------------------------------------*/ 117 118int16 median5(int16 x[]) 119{ 120 int16 x1, x2, x3, x4, x5; 121 int16 tmp; 122 123 x1 = x[-2]; 124 x2 = x[-1]; 125 x3 = x[0]; 126 x4 = x[1]; 127 x5 = x[2]; 128 129 130 131 if (x2 < x1) 132 { 133 tmp = x1; 134 x1 = x2; 135 x2 = tmp; 136 } 137 if (x3 < x1) 138 { 139 tmp = x1; 140 x1 = x3; 141 x3 = tmp; 142 } 143 if (x4 < x1) 144 { 145 tmp = x1; 146 x1 = x4; 147 x4 = tmp; 148 } 149 if (x5 < x1) 150 { 151 x5 = x1; 152 } 153 if (x3 < x2) 154 { 155 tmp = x2; 156 x2 = x3; 157 x3 = tmp; 158 } 159 if (x4 < x2) 160 { 161 tmp = x2; 162 x2 = x4; 163 x4 = tmp; 164 } 165 if (x5 < x2) 166 { 167 x5 = x2; 168 } 169 if (x4 < x3) 170 { 171 x3 = x4; 172 } 173 if (x5 < x3) 174 { 175 x3 = x5; 176 } 177 return (x3); 178} 179 180 181