1 /* 2 * Copyright (C) 2004-2010 NXP Software 3 * Copyright (C) 2010 The Android Open Source Project 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 /****************************************************************************************/ 19 /* */ 20 /* Includes */ 21 /* */ 22 /****************************************************************************************/ 23 #include "LVREV.h" 24 25 /****************************************************************************************/ 26 /* */ 27 /* Tables */ 28 /* */ 29 /****************************************************************************************/ 30 31 /* Table with supported sampling rates. The table can be indexed using LVM_Fs_en */ 32 const LVM_UINT16 LVM_FsTable[] = { 33 8000 , 34 11025, 35 12000, 36 16000, 37 22050, 38 24000, 39 32000, 40 44100, 41 48000 42 }; 43 44 /* Table with supported sampling rates. The table can be indexed using LVM_Fs_en */ 45 LVM_UINT16 LVM_GetFsFromTable(LVM_Fs_en FsIndex){ 46 if (FsIndex > LVM_FS_48000) 47 return 0; 48 49 return (LVM_FsTable[FsIndex]); 50 } 51 52 /* In order to maintain consistant input and out put signal strengths 53 output gain/attenuation is applied. This gain depends on T60 and Rooms 54 size parameters. These polynomial coefficients are calculated experimentally. 55 First value in the table is room size 56 second value is A0 57 third value is A1 58 fourth value is A2 59 fifth value is A3 60 sixth value is A4 61 62 shift value is to be added array (to use LVM_Polynomial function) 63 64 The gain is calculated using variable x=(T60*32767/7000)*32768; 65 66 first values is used to get polynomial set for given room size, 67 For room sizes which are not in the table, linear interpolation can be used. 68 69 */ 70 71 /* Normalizing output including Reverb Level part (only shift up)*/ 72 const LVM_INT32 LVREV_GainPolyTable[24][5]={{1,17547434,128867434,-120988896,50761228,}, 73 {2,18256869,172666902,-193169292,88345744,}, 74 {3,16591311,139250151,-149667234,66770059,}, 75 {4,17379977,170835131,-173579321,76278163,}, 76 {5,18963512,210364934,-228623519,103435022,}, 77 {6,17796318,135756417,-144084053,64327698,}, 78 {7,17454695,174593214,-187513064,85146582,}, 79 {8,17229257,140715570,-145790588,65361740,}, 80 {9,17000547,163195946,-176733969,79562130,}, 81 {10,16711699,142476304,-133339887,58366547,}, 82 {13,18108419,149223697,-161762020,74397589,}, 83 {15,16682043,124844884,-134284487,60082180,}, 84 {17,16627346,120936430,-121766674,53146421,}, 85 {20,17338325,125432694,-126616983,56534237,}, 86 {25,16489146,99218217,-94597467,40616506,}, 87 {30,15582373,84479043,-75365006,30952348,}, 88 {40,16000669,84896611,-75031127,30696306,}, 89 {50,15087054,71695031,-59349268,23279669,}, 90 {60,15830714,68672971,-58211201,23671158,}, 91 {70,15536061,66657972,-55901437,22560153,}, 92 {75,15013145,48179917,-24138354,5232074,}, 93 {80,15688738,50195036,-34206760,11515792,}, 94 {90,16003322,48323661,-35607378,13153872,}, 95 {100,15955223,48558201,-33706865,11715792,}, 96 }; 97 98 /* End of file */ 99 100
