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-rw-r--r--examples/multimedia/audiooutput/audiooutput.cpp334
-rw-r--r--examples/multimedia/audiooutput/audiooutput.h122
-rw-r--r--examples/multimedia/audiooutput/audiooutput.pro12
-rwxr-xr-xexamples/multimedia/audiooutput/doc/images/audiooutput-example.pngbin0 -> 11966 bytes
-rw-r--r--examples/multimedia/audiooutput/doc/src/audiooutput.qdoc43
-rw-r--r--examples/multimedia/audiooutput/main.cpp54
6 files changed, 565 insertions, 0 deletions
diff --git a/examples/multimedia/audiooutput/audiooutput.cpp b/examples/multimedia/audiooutput/audiooutput.cpp
new file mode 100644
index 000000000..4328e4e99
--- /dev/null
+++ b/examples/multimedia/audiooutput/audiooutput.cpp
@@ -0,0 +1,334 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+** of its contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QAudioDeviceInfo>
+#include <QAudioOutput>
+#include <QDebug>
+#include <QVBoxLayout>
+#include <qmath.h>
+#include <qendian.h>
+
+#include "audiooutput.h"
+
+#define PUSH_MODE_LABEL "Enable push mode"
+#define PULL_MODE_LABEL "Enable pull mode"
+#define SUSPEND_LABEL "Suspend playback"
+#define RESUME_LABEL "Resume playback"
+#define VOLUME_LABEL "Volume:"
+
+const int DurationSeconds = 1;
+const int ToneSampleRateHz = 600;
+const int DataSampleRateHz = 44100;
+const int BufferSize = 32768;
+
+
+Generator::Generator(const QAudioFormat &format,
+ qint64 durationUs,
+ int sampleRate,
+ QObject *parent)
+ : QIODevice(parent)
+ , m_pos(0)
+{
+ generateData(format, durationUs, sampleRate);
+}
+
+Generator::~Generator()
+{
+
+}
+
+void Generator::start()
+{
+ open(QIODevice::ReadOnly);
+}
+
+void Generator::stop()
+{
+ m_pos = 0;
+ close();
+}
+
+void Generator::generateData(const QAudioFormat &format, qint64 durationUs, int sampleRate)
+{
+ const int channelBytes = format.sampleSize() / 8;
+ const int sampleBytes = format.channelCount() * channelBytes;
+
+ qint64 length = (format.sampleRate() * format.channelCount() * (format.sampleSize() / 8))
+ * durationUs / 100000;
+
+ Q_ASSERT(length % sampleBytes == 0);
+ Q_UNUSED(sampleBytes) // suppress warning in release builds
+
+ m_buffer.resize(length);
+ unsigned char *ptr = reinterpret_cast<unsigned char *>(m_buffer.data());
+ int sampleIndex = 0;
+
+ while (length) {
+ const qreal x = qSin(2 * M_PI * sampleRate * qreal(sampleIndex % format.sampleRate()) / format.sampleRate());
+ for (int i=0; i<format.channelCount(); ++i) {
+ if (format.sampleSize() == 8 && format.sampleType() == QAudioFormat::UnSignedInt) {
+ const quint8 value = static_cast<quint8>((1.0 + x) / 2 * 255);
+ *reinterpret_cast<quint8*>(ptr) = value;
+ } else if (format.sampleSize() == 8 && format.sampleType() == QAudioFormat::SignedInt) {
+ const qint8 value = static_cast<qint8>(x * 127);
+ *reinterpret_cast<quint8*>(ptr) = value;
+ } else if (format.sampleSize() == 16 && format.sampleType() == QAudioFormat::UnSignedInt) {
+ quint16 value = static_cast<quint16>((1.0 + x) / 2 * 65535);
+ if (format.byteOrder() == QAudioFormat::LittleEndian)
+ qToLittleEndian<quint16>(value, ptr);
+ else
+ qToBigEndian<quint16>(value, ptr);
+ } else if (format.sampleSize() == 16 && format.sampleType() == QAudioFormat::SignedInt) {
+ qint16 value = static_cast<qint16>(x * 32767);
+ if (format.byteOrder() == QAudioFormat::LittleEndian)
+ qToLittleEndian<qint16>(value, ptr);
+ else
+ qToBigEndian<qint16>(value, ptr);
+ }
+
+ ptr += channelBytes;
+ length -= channelBytes;
+ }
+ ++sampleIndex;
+ }
+}
+
+qint64 Generator::readData(char *data, qint64 len)
+{
+ qint64 total = 0;
+ while (len - total > 0) {
+ const qint64 chunk = qMin((m_buffer.size() - m_pos), len - total);
+ memcpy(data + total, m_buffer.constData() + m_pos, chunk);
+ m_pos = (m_pos + chunk) % m_buffer.size();
+ total += chunk;
+ }
+ return total;
+}
+
+qint64 Generator::writeData(const char *data, qint64 len)
+{
+ Q_UNUSED(data);
+ Q_UNUSED(len);
+
+ return 0;
+}
+
+qint64 Generator::bytesAvailable() const
+{
+ return m_buffer.size() + QIODevice::bytesAvailable();
+}
+
+AudioTest::AudioTest()
+ : m_pullTimer(new QTimer(this))
+ , m_modeButton(0)
+ , m_suspendResumeButton(0)
+ , m_deviceBox(0)
+ , m_device(QAudioDeviceInfo::defaultOutputDevice())
+ , m_generator(0)
+ , m_audioOutput(0)
+ , m_output(0)
+ , m_buffer(BufferSize, 0)
+{
+ initializeWindow();
+ initializeAudio();
+}
+
+void AudioTest::initializeWindow()
+{
+ QScopedPointer<QWidget> window(new QWidget);
+ QScopedPointer<QVBoxLayout> layout(new QVBoxLayout);
+
+ m_deviceBox = new QComboBox(this);
+ foreach (const QAudioDeviceInfo &deviceInfo, QAudioDeviceInfo::availableDevices(QAudio::AudioOutput))
+ m_deviceBox->addItem(deviceInfo.deviceName(), qVariantFromValue(deviceInfo));
+ connect(m_deviceBox,SIGNAL(activated(int)),SLOT(deviceChanged(int)));
+ layout->addWidget(m_deviceBox);
+
+ m_modeButton = new QPushButton(this);
+ m_modeButton->setText(tr(PUSH_MODE_LABEL));
+ connect(m_modeButton, SIGNAL(clicked()), SLOT(toggleMode()));
+ layout->addWidget(m_modeButton);
+
+ m_suspendResumeButton = new QPushButton(this);
+ m_suspendResumeButton->setText(tr(SUSPEND_LABEL));
+ connect(m_suspendResumeButton, SIGNAL(clicked()), SLOT(toggleSuspendResume()));
+ layout->addWidget(m_suspendResumeButton);
+
+ QHBoxLayout *volumeBox = new QHBoxLayout;
+ m_volumeLabel = new QLabel;
+ m_volumeLabel->setText(tr(VOLUME_LABEL));
+ m_volumeSlider = new QSlider(Qt::Horizontal);
+ m_volumeSlider->setMinimum(0);
+ m_volumeSlider->setMaximum(100);
+ m_volumeSlider->setSingleStep(10);
+ connect(m_volumeSlider, SIGNAL(valueChanged(int)), this, SLOT(volumeChanged(int)));
+ volumeBox->addWidget(m_volumeLabel);
+ volumeBox->addWidget(m_volumeSlider);
+ layout->addLayout(volumeBox);
+
+ window->setLayout(layout.data());
+ layout.take(); // ownership transferred
+
+ setCentralWidget(window.data());
+ QWidget *const windowPtr = window.take(); // ownership transferred
+ windowPtr->show();
+}
+
+void AudioTest::initializeAudio()
+{
+ connect(m_pullTimer, SIGNAL(timeout()), SLOT(pullTimerExpired()));
+
+ m_pullMode = true;
+
+ m_format.setSampleRate(DataSampleRateHz);
+ m_format.setChannelCount(1);
+ m_format.setSampleSize(16);
+ m_format.setCodec("audio/pcm");
+ m_format.setByteOrder(QAudioFormat::LittleEndian);
+ m_format.setSampleType(QAudioFormat::SignedInt);
+
+ QAudioDeviceInfo info(QAudioDeviceInfo::defaultOutputDevice());
+ if (!info.isFormatSupported(m_format)) {
+ qWarning() << "Default format not supported - trying to use nearest";
+ m_format = info.nearestFormat(m_format);
+ }
+
+ m_generator = new Generator(m_format, DurationSeconds*1000000, ToneSampleRateHz, this);
+
+ createAudioOutput();
+}
+
+void AudioTest::createAudioOutput()
+{
+ delete m_audioOutput;
+ m_audioOutput = 0;
+ m_audioOutput = new QAudioOutput(m_device, m_format, this);
+ connect(m_audioOutput, SIGNAL(notify()), SLOT(notified()));
+ connect(m_audioOutput, SIGNAL(stateChanged(QAudio::State)), SLOT(stateChanged(QAudio::State)));
+ m_generator->start();
+ m_audioOutput->start(m_generator);
+ m_volumeSlider->setValue(int(m_audioOutput->volume()*100.0f));
+}
+
+AudioTest::~AudioTest()
+{
+
+}
+
+void AudioTest::deviceChanged(int index)
+{
+ m_pullTimer->stop();
+ m_generator->stop();
+ m_audioOutput->stop();
+ m_audioOutput->disconnect(this);
+ m_device = m_deviceBox->itemData(index).value<QAudioDeviceInfo>();
+ createAudioOutput();
+}
+
+void AudioTest::volumeChanged(int value)
+{
+ if (m_audioOutput)
+ m_audioOutput->setVolume(qreal(value/100.0f));
+}
+
+void AudioTest::notified()
+{
+ qWarning() << "bytesFree = " << m_audioOutput->bytesFree()
+ << ", " << "elapsedUSecs = " << m_audioOutput->elapsedUSecs()
+ << ", " << "processedUSecs = " << m_audioOutput->processedUSecs();
+}
+
+void AudioTest::pullTimerExpired()
+{
+ if (m_audioOutput && m_audioOutput->state() != QAudio::StoppedState) {
+ int chunks = m_audioOutput->bytesFree()/m_audioOutput->periodSize();
+ while (chunks) {
+ const qint64 len = m_generator->read(m_buffer.data(), m_audioOutput->periodSize());
+ if (len)
+ m_output->write(m_buffer.data(), len);
+ if (len != m_audioOutput->periodSize())
+ break;
+ --chunks;
+ }
+ }
+}
+
+void AudioTest::toggleMode()
+{
+ m_pullTimer->stop();
+ m_audioOutput->stop();
+
+ if (m_pullMode) {
+ m_modeButton->setText(tr(PULL_MODE_LABEL));
+ m_output = m_audioOutput->start();
+ m_pullMode = false;
+ m_pullTimer->start(20);
+ } else {
+ m_modeButton->setText(tr(PUSH_MODE_LABEL));
+ m_pullMode = true;
+ m_audioOutput->start(m_generator);
+ }
+
+ m_suspendResumeButton->setText(tr(SUSPEND_LABEL));
+}
+
+void AudioTest::toggleSuspendResume()
+{
+ if (m_audioOutput->state() == QAudio::SuspendedState) {
+ qWarning() << "status: Suspended, resume()";
+ m_audioOutput->resume();
+ m_suspendResumeButton->setText(tr(SUSPEND_LABEL));
+ } else if (m_audioOutput->state() == QAudio::ActiveState) {
+ qWarning() << "status: Active, suspend()";
+ m_audioOutput->suspend();
+ m_suspendResumeButton->setText(tr(RESUME_LABEL));
+ } else if (m_audioOutput->state() == QAudio::StoppedState) {
+ qWarning() << "status: Stopped, resume()";
+ m_audioOutput->resume();
+ m_suspendResumeButton->setText(tr(SUSPEND_LABEL));
+ } else if (m_audioOutput->state() == QAudio::IdleState) {
+ qWarning() << "status: IdleState";
+ }
+}
+
+void AudioTest::stateChanged(QAudio::State state)
+{
+ qWarning() << "state = " << state;
+}
diff --git a/examples/multimedia/audiooutput/audiooutput.h b/examples/multimedia/audiooutput/audiooutput.h
new file mode 100644
index 000000000..52c29cc79
--- /dev/null
+++ b/examples/multimedia/audiooutput/audiooutput.h
@@ -0,0 +1,122 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+** of its contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef AUDIOOUTPUT_H
+#define AUDIOOUTPUT_H
+
+#include <math.h>
+
+#include <QAudioOutput>
+#include <QByteArray>
+#include <QComboBox>
+#include <QIODevice>
+#include <QLabel>
+#include <QMainWindow>
+#include <QObject>
+#include <QPushButton>
+#include <QSlider>
+#include <QTimer>
+
+class Generator : public QIODevice
+{
+ Q_OBJECT
+
+public:
+ Generator(const QAudioFormat &format, qint64 durationUs, int sampleRate, QObject *parent);
+ ~Generator();
+
+ void start();
+ void stop();
+
+ qint64 readData(char *data, qint64 maxlen);
+ qint64 writeData(const char *data, qint64 len);
+ qint64 bytesAvailable() const;
+
+private:
+ void generateData(const QAudioFormat &format, qint64 durationUs, int sampleRate);
+
+private:
+ qint64 m_pos;
+ QByteArray m_buffer;
+};
+
+class AudioTest : public QMainWindow
+{
+ Q_OBJECT
+
+public:
+ AudioTest();
+ ~AudioTest();
+
+private:
+ void initializeWindow();
+ void initializeAudio();
+ void createAudioOutput();
+
+private:
+ QTimer *m_pullTimer;
+
+ // Owned by layout
+ QPushButton *m_modeButton;
+ QPushButton *m_suspendResumeButton;
+ QComboBox *m_deviceBox;
+ QLabel *m_volumeLabel;
+ QSlider *m_volumeSlider;
+
+ QAudioDeviceInfo m_device;
+ Generator *m_generator;
+ QAudioOutput *m_audioOutput;
+ QIODevice *m_output; // not owned
+ QAudioFormat m_format;
+
+ bool m_pullMode;
+ QByteArray m_buffer;
+
+private slots:
+ void notified();
+ void pullTimerExpired();
+ void toggleMode();
+ void toggleSuspendResume();
+ void stateChanged(QAudio::State state);
+ void deviceChanged(int index);
+ void volumeChanged(int);
+};
+
+#endif // AUDIOOUTPUT_H
diff --git a/examples/multimedia/audiooutput/audiooutput.pro b/examples/multimedia/audiooutput/audiooutput.pro
new file mode 100644
index 000000000..c843f010f
--- /dev/null
+++ b/examples/multimedia/audiooutput/audiooutput.pro
@@ -0,0 +1,12 @@
+TEMPLATE = app
+TARGET = audiooutput
+
+QT += multimedia widgets
+
+HEADERS = audiooutput.h
+
+SOURCES = audiooutput.cpp \
+ main.cpp
+
+target.path = $$[QT_INSTALL_EXAMPLES]/multimedia/audiooutput
+INSTALLS += target
diff --git a/examples/multimedia/audiooutput/doc/images/audiooutput-example.png b/examples/multimedia/audiooutput/doc/images/audiooutput-example.png
new file mode 100755
index 000000000..5588fbb57
--- /dev/null
+++ b/examples/multimedia/audiooutput/doc/images/audiooutput-example.png
Binary files differ
diff --git a/examples/multimedia/audiooutput/doc/src/audiooutput.qdoc b/examples/multimedia/audiooutput/doc/src/audiooutput.qdoc
new file mode 100644
index 000000000..c29fcd81d
--- /dev/null
+++ b/examples/multimedia/audiooutput/doc/src/audiooutput.qdoc
@@ -0,0 +1,43 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: http://www.gnu.org/copyleft/fdl.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+ \example audiooutput
+ \title Audio Output Example
+ \ingroup audio_examples
+ \brief The Audio Output Example show the use of the QAudioOutput API.
+
+ The example demonstrates the basic use cases of the QAudioOutput class.
+
+ \image audiooutput-example.png
+
+ This example provides a tone generator to supply continuous audio playback.
+ The first button allows pause and resume of the playback, and the second
+ button allows toggling between push and pull modes of operation.
+*/
+
+
diff --git a/examples/multimedia/audiooutput/main.cpp b/examples/multimedia/audiooutput/main.cpp
new file mode 100644
index 000000000..097cabb7b
--- /dev/null
+++ b/examples/multimedia/audiooutput/main.cpp
@@ -0,0 +1,54 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+** of its contributors may be used to endorse or promote products derived
+** from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QApplication>
+
+#include "audiooutput.h"
+
+int main(int argc, char *argv[])
+{
+ QApplication app(argc, argv);
+ app.setApplicationName("Audio Output Test");
+
+ AudioTest audio;
+ audio.show();
+
+ return app.exec();
+}