1// Copyright (C) 2021 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#include <qaudiooutput.h>
5#include <qaudiodevice.h>
6#include <qmediadevices.h>
7#include <private/qplatformaudiooutput_p.h>
8#include <private/qplatformmediaintegration_p.h>
9
10/*!
11 \qmltype AudioOutput
12 \nativetype QAudioOutput
13 \brief An audio output to be used for playback or monitoring of a capture session.
14
15 \inqmlmodule QtMultimedia
16 \ingroup multimedia_qml
17 \ingroup multimedia_audio_qml
18
19 \qml
20 MediaPlayer {
21 id: playMusic
22 source: "music.wav"
23 audioOutput: AudioOutput {
24 volume: slider.value
25 }
26 }
27 Slider {
28 id: slider
29 from: 0.
30 to: 1.
31 }
32 \endqml
33
34 You can use AudioOutput together with a QtMultiMedia::MediaPlayer to play audio content, or you
35 can use it in conjunction with a MultiMedia::CaptureSession to monitor the audio processed by the
36 capture session.
37
38 \sa VideoOutput, AudioInput
39*/
40
41/*!
42 \class QAudioOutput
43 \brief Represents an output channel for audio.
44 \inmodule QtMultimedia
45 \ingroup multimedia
46 \ingroup multimedia_audio
47 \since 6.0
48
49 This class represents an output channel that can be used together with
50 QMediaPlayer or QMediaCaptureSession. It enables the selection of the
51 physical output device to be used, muting the channel, and changing the
52 channel's volume.
53*/
54QAudioOutput::QAudioOutput(QObject *parent)
55 : QAudioOutput(QMediaDevices::defaultAudioOutput(), parent)
56{
57}
58
59QAudioOutput::QAudioOutput(const QAudioDevice &device, QObject *parent)
60 : QObject(parent)
61{
62 auto maybeAudioOutput = QPlatformMediaIntegration::instance()->createAudioOutput(this);
63 if (maybeAudioOutput) {
64 d = maybeAudioOutput.value();
65 d->device = device.mode() == QAudioDevice::Output ? device : QMediaDevices::defaultAudioOutput();
66 d->setAudioDevice(d->device);
67 } else {
68 d = new QPlatformAudioOutput(nullptr);
69 qWarning() << "Failed to initialize QAudioOutput" << maybeAudioOutput.error();
70 }
71}
72
73QAudioOutput::~QAudioOutput()
74{
75 setDisconnectFunction({});
76 delete d;
77}
78
79/*!
80 \qmlproperty real QtMultimedia::AudioOutput::volume
81
82 This property holds the volume of the audio output.
83
84 The volume is scaled linearly from \c 0.0 (silence) to \c 1.0 (full volume).
85 Values outside this range will be clamped: a value lower than 0.0 is set to
86 0.0, a value higher than 1.0 will set to 1.0.
87
88 The default volume is \c{1.0}.
89
90 UI \l{volume controls} should usually be scaled non-linearly. For example,
91 using a logarithmic scale will produce linear changes in perceived \l{loudness},
92 which is what a user would normally expect from a volume control.
93
94 See \l {QtAudio::convertVolume()}{QtMultimedia.convertVolume()}
95 for more details.
96*/
97
98/*!
99 \property QAudioOutput::volume
100 \brief The current volume.
101
102 The volume is scaled linearly, ranging from \c 0 (silence) to \c 1
103 (full volume).
104 \note values outside this range will be clamped.
105
106 By default the volume is \c 1.
107
108 UI volume controls should usually be scaled non-linearly. For example,
109 using a logarithmic scale will produce linear changes in perceived loudness,
110 which is what a user would normally expect from a volume control.
111
112 \sa QtAudio::convertVolume()
113*/
114float QAudioOutput::volume() const
115{
116 return d->volume;
117}
118
119void QAudioOutput::setVolume(float volume)
120{
121 volume = qBound(min: 0., val: volume, max: 1.);
122 if (d->volume == volume)
123 return;
124 d->volume = volume;
125 d->setVolume(volume);
126 emit volumeChanged(volume);
127}
128
129/*!
130 \qmlproperty bool QtMultimedia::AudioOutput::muted
131
132 This property holds whether the audio output is muted.
133
134 Defaults to \c{false}.
135*/
136
137/*!
138 \property QAudioOutput::muted
139 \brief The muted state of the current media.
140
141 The value will be \c true if the output is muted; otherwise \c{false}.
142*/
143bool QAudioOutput::isMuted() const
144{
145 return d->muted;
146}
147
148void QAudioOutput::setMuted(bool muted)
149{
150 if (d->muted == muted)
151 return;
152 d->muted = muted;
153 d->setMuted(muted);
154 emit mutedChanged(muted);
155}
156
157/*!
158 \qmlproperty AudioDevice QtMultimedia::AudioOutput::device
159
160 This property describes the audio device connected to this output.
161
162 The device property represents the audio device this output is connected to.
163 This property can be used to select an output device from the
164 QtMultimedia::MediaDevices::audioOutputs() list.
165*/
166
167/*!
168 \property QAudioOutput::device
169 \brief The audio device connected to this output.
170
171 The device property represents the audio device this output is connected to.
172 This property can be used to select an output device from the
173 QMediaDevices::audioOutputs() list.
174 You can select the system default audio output by setting this property to
175 a default constructed QAudioDevice object.
176*/
177QAudioDevice QAudioOutput::device() const
178{
179 return d->device;
180}
181
182void QAudioOutput::setDevice(const QAudioDevice &device)
183{
184 auto dev = device;
185 if (dev.isNull())
186 dev = QMediaDevices::defaultAudioOutput();
187 if (dev.mode() != QAudioDevice::Output)
188 return;
189 if (d->device == dev)
190 return;
191 d->device = dev;
192 d->setAudioDevice(dev);
193 emit deviceChanged();
194}
195
196/*!
197 \internal
198*/
199void QAudioOutput::setDisconnectFunction(std::function<void()> disconnectFunction)
200{
201 if (d->disconnectFunction) {
202 auto df = d->disconnectFunction;
203 d->disconnectFunction = {};
204 df();
205 }
206 d->disconnectFunction = std::move(disconnectFunction);
207}
208
209#include "moc_qaudiooutput.cpp"
210

source code of qtmultimedia/src/multimedia/audio/qaudiooutput.cpp