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/****************************************************************************
**
** Copyright (C) 2013 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 multimedia/audiorecorder
\title Audio Recorder Example
\ingroup multimedia_examples
\brief The Audio Recorder Example shows how to create a simple audio recorder.
It demonstrates the discovery of the supported devices and codecs and the use
of recording functions in the QAudioRecorder class.
We display a window for the user to select the appropriate audio input,
codec, container, and sample rate. Allow a setting of either quality or
bitrate. Finally, the output file can be selected and recording can be
started.
The lists are setup using the \l{QAudioRecorder::audioInputs()}{audioInputs()},
\l{QAudioRecorder::supportedAudioCodecs()}{supportedAudioCodecs()},
\l{QAudioRecorder::supportedContainers()}{supportedContainers()},
\l{QAudioRecorder::supportedContainers()}{supportedContainers()}, and
\l{QAudioRecorder::supportedAudioSampleRates()}{supportedAudioSampleRates()}
methods. The quality slider is setup from 0 (zero) to
\l{QMultimedia::VeryHighQuality} with a default value of
\l{QMultimedia::NormalQuality}, while the bitrates are hardcoded
into the list.
\image audiorecorder.png
To record audio we simply create a QAudioRecorder object.
\code
audioRecorder = new QAudioRecorder(this);
\endcode
And setup the lists as described above. The text on the record and pause
buttons are toggled depending on the \l{QMediaRecorder::State}{state} of
the \c audioRecorder object. This means that if the state is
\l{QMediaRecorder::StoppedState} then the button text will be "Record" and
"Pause". In \l{QMediaRecorder::RecordingState} the record button will have
the text "Stop", and in \l{QMediaRecorder::PausedState} the pause button
will have the text "Resume".
Pressing the buttons will also result in a toggle based on the state. If
recording is stopped, then pressing the record button will setup the
\l{QAudioEncoderSettings} based on the values of the selection lists,
will set the encoding settings and container on the \c audioRecorder
object, and start recording using the
\l{QMediaRecorder::record()}{record()} method.
\code
QAudioEncoderSettings settings;
settings.setCodec(boxValue(ui->audioCodecBox).toString());
settings.setSampleRate(boxValue(ui->sampleRateBox).toInt());
settings.setBitRate(boxValue(ui->bitrateBox).toInt());
settings.setQuality(QMultimedia::EncodingQuality(ui->qualitySlider->value()));
settings.setEncodingMode(ui->constantQualityRadioButton->isChecked() ?
QMultimedia::ConstantQualityEncoding :
QMultimedia::ConstantBitRateEncoding);
QString container = boxValue(ui->containerBox).toString();
audioRecorder->setEncodingSettings(settings, QVideoEncoderSettings(), container);
audioRecorder->record();
\endcode
While recording, the status bar of the application is updated with duration information
from the \l{QMediaRecorder::durationChanged()}{durationChanged} signal from the
\c audioRecorder object.
\code
ui->statusbar->showMessage(tr("Recorded %1 sec").arg(duration / 1000));
\endcode
*/
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