1 /***************************************************************************
2  *   Copyright (C) 2011 by Pere R�fols Soler                               *
3  *   sapista2@gmail.com                                                    *
4  *                                                                         *
5  *   This program is free software; you can redistribute it and/or modify  *
6  *   it under the terms of the GNU General Public License as published by  *
7  *   the Free Software Foundation; either version 2 of the License, or     *
8  *   (at your option) any later version.                                   *
9  *                                                                         *
10  *   This program is distributed in the hope that it will be useful,       *
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
13  *   GNU General Public License for more details.                          *
14  *                                                                         *
15  *   You should have received a copy of the GNU General Public License     *
16  *   along with this program; if not, write to the                         *
17  *   Free Software Foundation, Inc.,                                       *
18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
19  ***************************************************************************/
20 
21 /***************************************************************************
22 This file contains a VU meter implementation
23 ****************************************************************************/
24 
25 #include "vu.h"
26 //#include <stdio.h>
27 #include <stdlib.h>
28 
29 //Constant to dBu conversion is sqrt(2)
30 #define CONSTANT_VU 1.4142136
31 
32 //Initialize the VU meter
VuInit(double rate)33 Vu *VuInit(double rate)
34 {
35   Vu *vu = (Vu *)malloc(sizeof(Vu));
36 
37   vu->vu_value = 0.0;
38   vu->vu_max = 0.0;
39 
40   vu->m_min = (1.0 / 256);
41   vu->m_decay = exp( -1.0 / rate);
42 
43   return vu;
44 }
45 
46 //Destroy a Vu instance
VuClean(Vu * vu)47 void VuClean(Vu *vu){
48   free(vu);
49 }
50