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Diffstat (limited to 'src/multimedia/audio/qaudioprobe.cpp')
-rw-r--r-- | src/multimedia/audio/qaudioprobe.cpp | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/src/multimedia/audio/qaudioprobe.cpp b/src/multimedia/audio/qaudioprobe.cpp new file mode 100644 index 000000000..e51c56a7c --- /dev/null +++ b/src/multimedia/audio/qaudioprobe.cpp @@ -0,0 +1,188 @@ +/**************************************************************************** +** +** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). +** Contact: http://www.qt-project.org/ +** +** This file is part of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this +** file. Please review the following information to ensure the GNU Lesser +** General Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU General +** Public License version 3.0 as published by the Free Software Foundation +** and appearing in the file LICENSE.GPL included in the packaging of this +** file. Please review the following information to ensure the GNU General +** Public License version 3.0 requirements will be met: +** http://www.gnu.org/copyleft/gpl.html. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \class QAudioProbe + \inmodule QtMultimedia + + \ingroup multimedia + \ingroup multimedia_video + + \brief The QAudioProbe class allows you to monitor audio being played or recorded. + + \code + QAudioRecorder *recorder = new QAudioRecorder(); + QAudioProbe *probe = new QAudioProbe; + + // ... configure the audio recorder (skipped) + + connect(probe, SIGNAL(audioBufferProbed(QAudioBuffer)), this, SLOT(processBuffer(QAudioBuffer))); + + probe->setSource(recorder); // Returns true, hopefully. + + recorder->record(); // Now we can do things like calculating levels or performing an FFT + \endcode + + \sa QVideoProbe, QMediaPlayer, QCamera +*/ + +#include "qaudioprobe.h" +#include "qmediaaudioprobecontrol.h" +#include "qmediaservice.h" +#include "qmediarecorder.h" +#include "qsharedpointer.h" + +QT_BEGIN_NAMESPACE + +class QAudioProbePrivate { +public: + QWeakPointer<QMediaObject> source; + QWeakPointer<QMediaAudioProbeControl> probee; +}; + +/*! + Creates a new QAudioProbe class. After setting the + source to monitor with \l setSource(), the \l audioBufferProbed() + signal will be emitted when audio buffers are flowing in the + source media object. + */ +QAudioProbe::QAudioProbe(QObject *parent) + : QObject(parent) + , d(new QAudioProbePrivate) +{ +} + +/*! + Destroys this probe and disconnects from any + media object. + */ +QAudioProbe::~QAudioProbe() +{ + if (d->source) { + // Disconnect + if (d->probee) + disconnect(d->probee.data(), SIGNAL(audioBufferProbed(QAudioBuffer)), this, SIGNAL(audioBufferProbed(QAudioBuffer))); + d->source.data()->service()->releaseControl(d->probee.data()); + } +} + +/*! + Sets the media object to monitor to \a source. + + If \a source is zero, this probe will be deactivated + and this function wil return true. + + If the media object does not support monitoring + audio, this function will return false. + + The previous object will no longer be monitored. + Passing in the same object will be ignored, but + monitoring will continue. + */ +bool QAudioProbe::setSource(QMediaObject *source) +{ + // Need to: + // 1) disconnect from current source if necessary + // 2) see if new one has the probe control + // 3) connect if so + if (source != d->source.data()) { + if (d->source) { + Q_ASSERT(d->probee); + disconnect(d->probee.data(), SIGNAL(audioBufferProbed(QAudioBuffer)), this, SIGNAL(audioBufferProbed(QAudioBuffer))); + d->source.data()->service()->releaseControl(d->probee.data()); + d->source.clear(); + d->probee.clear(); + } + + if (source) { + QMediaService *service = source->service(); + if (service) { + d->probee = service->requestControl<QMediaAudioProbeControl*>(); + } + + if (d->probee) { + connect(d->probee.data(), SIGNAL(audioBufferProbed(QAudioBuffer)), this, SIGNAL(audioBufferProbed(QAudioBuffer))); + d->source = source; + } + } + } + + return (!source || d->probee != 0); +} + +/*! + Starts monitoring the given \a mediaRecorder. + + If \a source is zero, this probe will be deactivated + and this function wil return true. + + If the media recorder instance does not support monitoring + audio, this function will return false. + + Any previously monitored objects will no longer be monitored. + Passing in the same object will be ignored, but + monitoring will continue. + */ +bool QAudioProbe::setSource(QMediaRecorder *mediaRecorder) +{ + QMediaObject *source = mediaRecorder ? mediaRecorder->mediaObject() : 0; + bool result = setSource(source); + + if (!mediaRecorder) + return true; + + if (mediaRecorder && !source) + return false; + + return result; +} + +/*! + Returns true if this probe is monitoring something, or false otherwise. + + The source being monitored does not need to be active. + */ +bool QAudioProbe::isActive() const +{ + return d->probee != 0; +} + +QT_END_NAMESPACE |