1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*************************************************************************
LevelMeter.h - multi-track audio level meter
-------------------
view copyright : Copyright 2002 Rik Hemsley (rikkus) <rik@kde.org>
begin : Mon Nov 17 2003
copyright : (C) 2003 by Thomas Eschenbacher
email : Thomas.Eschenbacher@gmx.de
***************************************************************************/
/***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
#ifndef LEVEL_METER_H
#define LEVEL_METER_H
#include "config.h"
#include <QColor>
#include <QQueue>
#include <QTimer>
#include <QVector>
#include <QWidget>
#include "libkwave/Sample.h"
#include "libkwave/SampleArray.h"
class QPaintEvent;
namespace Kwave
{
class LevelMeter: public QWidget
{
Q_OBJECT
public:
/** Constructor */
explicit LevelMeter(QWidget *parent);
/** Destructor */
~LevelMeter() override;
/** @see QWidget::paintEvent */
void paintEvent(QPaintEvent *) override;
/** @see QWidget::resizeEvent */
void resizeEvent(QResizeEvent *) override;
public slots:
/** sets the number of tracks that the display should use */
virtual void setTracks(unsigned int tracks);
/**
* sets the sample rate for interpreting the samples used
* for updating the display.
*/
virtual void setSampleRate(double rate);
/**
* Updates a apecific track
* @param track index of the track
* @param buffer array with samples
*/
virtual void updateTrack(unsigned int track,
const Kwave::SampleArray &buffer);
/**
* Resets all meters to zero
*/
virtual void reset();
/**
* Redraws the whole widget
* @author (original idea taken from) Rik Hemsley (rikkus) <rik@kde.org>
* Copyright 2002
*/
virtual void drawContents();
protected slots:
/** Called via m_timer to update the bar(s) */
virtual void timedUpdate();
protected:
/**
* Enqueue a pair of fast and peak value of a track for later timed
* update. If the queue already contains the maximum number of elements,
* the oldest ones will be removed.
*
* @param track index of the track [0...m_tracks-1]
* @param fast value of the fast level bar [0.0 ... 1.0]
* @param peak value of the peak level [0.0 ... 1.0]
* @param queue_depth maximum number of elements to queue
*/
virtual void enqueue(unsigned int track, float fast, float peak,
unsigned int queue_depth);
/**
* Dequeue a pair of fast and peek value of a track.
* @param track index of the track [0...m_tracks-1]
* @param fast receives the value of the fast level bar [0.0 ... 1.0]
* @param peak receives value of the peak level [0.0 ... 1.0]
* @return true if there was something to dequeue, false if
* the queue was empty.
* @note fast and peak will not be modified if the queue was empty
*/
virtual bool dequeue(unsigned int track, float &fast, float &peak);
/**
* Draw some scale into the meter, using 3dB steps
* @param p an already opened QPainter
*/
void drawScale(QPainter &p);
private:
/** number of tracks */
int m_tracks;
/** sample rate used for interpreting the received buffers */
float m_sample_rate;
/** last output value of the filter for fast updates */
QVector<float> m_yf;
/** last output value of the filter for peak updates */
QVector<float> m_yp;
/** queues with fast update values for each track */
QVector< QQueue<float> > m_fast_queue;
/** queues with peak values for each track */
QVector< QQueue<float> > m_peak_queue;
/** current fast value for each track */
QVector<float> m_current_fast;
/** current peak value for each track */
QVector<float> m_current_peak;
/** timer for display updates */
QTimer *m_timer;
/** color for low levels, below -3dB */
QColor m_color_low;
/** color for normal levels, -3dB...-1.5dB */
QColor m_color_normal;
/** color high levels, above -1.5dB */
QColor m_color_high;
};
}
#endif /* LEVEL_METER_H */
//***************************************************************************
//***************************************************************************
|
