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Diffstat (limited to 'src/multimedia/mediaservices/base/qmediaserviceprovider.cpp')
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1 files changed, 738 insertions, 0 deletions
diff --git a/src/multimedia/mediaservices/base/qmediaserviceprovider.cpp b/src/multimedia/mediaservices/base/qmediaserviceprovider.cpp new file mode 100644 index 0000000..f27628b --- /dev/null +++ b/src/multimedia/mediaservices/base/qmediaserviceprovider.cpp @@ -0,0 +1,738 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtMediaServices module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, 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. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include <QtCore/qdebug.h> +#include <QtCore/qmap.h> + +#include <QtMediaServices/qmediaservice.h> +#include <QtMediaServices/qmediaserviceprovider.h> +#include <QtMediaServices/qmediaserviceproviderplugin.h> +#include "qmediapluginloader_p.h" +#include <QtMediaServices/qmediaplayer.h> + +QT_BEGIN_NAMESPACE + +class QMediaServiceProviderHintPrivate : public QSharedData +{ +public: + QMediaServiceProviderHintPrivate(QMediaServiceProviderHint::Type type) + :type(type), features(0) + { + } + + QMediaServiceProviderHintPrivate(const QMediaServiceProviderHintPrivate &other) + :QSharedData(other), + type(other.type), + device(other.device), + mimeType(other.mimeType), + codecs(other.codecs), + features(other.features) + { + } + + ~QMediaServiceProviderHintPrivate() + { + } + + QMediaServiceProviderHint::Type type; + QByteArray device; + QString mimeType; + QStringList codecs; + QMediaServiceProviderHint::Features features; +}; + +/*! + \class QMediaServiceProviderHint + \preliminary + \since 4.7 + \brief The QMediaServiceProviderHint class describes what is required of a QMediaService. + + \ingroup multimedia-serv + + The QMediaServiceProvider class uses hints to select an appropriate media service. +*/ + +/*! + \enum QMediaServiceProviderHint::Feature + + Enumerates features a media service may provide. + + \value LowLatencyPlayback + The service is expected to play simple audio formats, + but playback should start without significant delay. + Such playback service can be used for beeps, ringtones, etc. + + \value RecordingSupport + The service provides audio or video recording functions. + + \value StreamPlayback + The service is capable of playing QIODevice based streams. +*/ + +/*! + \enum QMediaServiceProviderHint::Type + + Enumerates the possible types of media service provider hint. + + \value Null En empty hint, use the default service. + \value ContentType Select media service most suitable for certain content type. + \value Device Select media service which supports certain device. + \value SupportedFeatures Select media service supporting the set of optional features. +*/ + + +/*! + Constructs an empty media service provider hint. +*/ +QMediaServiceProviderHint::QMediaServiceProviderHint() + :d(new QMediaServiceProviderHintPrivate(Null)) +{ +} + +/*! + Constructs a ContentType media service provider hint. + + This type of hint describes a service that is able to play content of a specific MIME \a type + encoded with one or more of the listed \a codecs. +*/ +QMediaServiceProviderHint::QMediaServiceProviderHint(const QString &type, const QStringList& codecs) + :d(new QMediaServiceProviderHintPrivate(ContentType)) +{ + d->mimeType = type; + d->codecs = codecs; +} + +/*! + Constructs a Device media service provider hint. + + This type of hint describes a media service that utilizes a specific \a device. +*/ +QMediaServiceProviderHint::QMediaServiceProviderHint(const QByteArray &device) + :d(new QMediaServiceProviderHintPrivate(Device)) +{ + d->device = device; +} + +/*! + Constructs a SupportedFeatures media service provider hint. + + This type of hint describes a service which supports a specific set of \a features. +*/ +QMediaServiceProviderHint::QMediaServiceProviderHint(QMediaServiceProviderHint::Features features) + :d(new QMediaServiceProviderHintPrivate(SupportedFeatures)) +{ + d->features = features; +} + +/*! + Constructs a copy of the media service provider hint \a other. +*/ +QMediaServiceProviderHint::QMediaServiceProviderHint(const QMediaServiceProviderHint &other) + :d(other.d) +{ +} + +/*! + Destroys a media service provider hint. +*/ +QMediaServiceProviderHint::~QMediaServiceProviderHint() +{ +} + +/*! + Assigns the value \a other to a media service provider hint. +*/ +QMediaServiceProviderHint& QMediaServiceProviderHint::operator=(const QMediaServiceProviderHint &other) +{ + d = other.d; + return *this; +} + +/*! + Identifies if \a other is of equal value to a media service provider hint. + + Returns true if the hints are equal, and false if they are not. +*/ +bool QMediaServiceProviderHint::operator == (const QMediaServiceProviderHint &other) const +{ + return (d == other.d) || + (d->type == other.d->type && + d->device == other.d->device && + d->mimeType == other.d->mimeType && + d->codecs == other.d->codecs && + d->features == other.d->features); +} + +/*! + Identifies if \a other is not of equal value to a media service provider hint. + + Returns true if the hints are not equal, and false if they are. +*/ +bool QMediaServiceProviderHint::operator != (const QMediaServiceProviderHint &other) const +{ + return !(*this == other); +} + +/*! + Returns true if a media service provider is null. +*/ +bool QMediaServiceProviderHint::isNull() const +{ + return d->type == Null; +} + +/*! + Returns the type of a media service provider hint. +*/ +QMediaServiceProviderHint::Type QMediaServiceProviderHint::type() const +{ + return d->type; +} + +/*! + Returns the mime type of the media a service is expected to be able play. +*/ +QString QMediaServiceProviderHint::mimeType() const +{ + return d->mimeType; +} + +/*! + Returns a list of codes a media service is expected to be able to decode. +*/ +QStringList QMediaServiceProviderHint::codecs() const +{ + return d->codecs; +} + +/*! + Returns the name of a device a media service is expected to utilize. +*/ +QByteArray QMediaServiceProviderHint::device() const +{ + return d->device; +} + +/*! + Returns a set of features a media service is expected to provide. +*/ +QMediaServiceProviderHint::Features QMediaServiceProviderHint::features() const +{ + return d->features; +} + + +Q_GLOBAL_STATIC_WITH_ARGS(QMediaPluginLoader, loader, + (QMediaServiceProviderFactoryInterface_iid, QLatin1String("/mediaservices"), Qt::CaseInsensitive)) + + +class QPluginServiceProvider : public QMediaServiceProvider +{ + QMap<QMediaService*, QMediaServiceProviderPlugin*> pluginMap; + +public: + QMediaService* requestService(const QByteArray &type, const QMediaServiceProviderHint &hint) + { + QString key(QString::fromLatin1(type.constData(),type.length())); + + QList<QMediaServiceProviderPlugin *>plugins; + foreach (QObject *obj, loader()->instances(key)) { + QMediaServiceProviderPlugin *plugin = + qobject_cast<QMediaServiceProviderPlugin*>(obj); + if (plugin) + plugins << plugin; + } + + if (!plugins.isEmpty()) { + QMediaServiceProviderPlugin *plugin = 0; + + switch (hint.type()) { + case QMediaServiceProviderHint::Null: + plugin = plugins[0]; + //special case for media player, if low latency was not asked, + //prefer services not offering it, since they are likely to support + //more formats + if (type == QByteArray(Q_MEDIASERVICE_MEDIAPLAYER)) { + foreach (QMediaServiceProviderPlugin *currentPlugin, plugins) { + QMediaServiceFeaturesInterface *iface = + qobject_cast<QMediaServiceFeaturesInterface*>(currentPlugin); + + if (!iface || !(iface->supportedFeatures(type) & + QMediaServiceProviderHint::LowLatencyPlayback)) { + plugin = currentPlugin; + break; + } + + } + } + break; + case QMediaServiceProviderHint::SupportedFeatures: + plugin = plugins[0]; + foreach (QMediaServiceProviderPlugin *currentPlugin, plugins) { + QMediaServiceFeaturesInterface *iface = + qobject_cast<QMediaServiceFeaturesInterface*>(currentPlugin); + + if (iface) { + if ((iface->supportedFeatures(type) & hint.features()) == hint.features()) { + plugin = currentPlugin; + break; + } + } + } + break; + case QMediaServiceProviderHint::Device: { + foreach (QMediaServiceProviderPlugin *currentPlugin, plugins) { + QMediaServiceSupportedDevicesInterface *iface = + qobject_cast<QMediaServiceSupportedDevicesInterface*>(currentPlugin); + + if (!iface) { + // the plugin may support the device, + // but this choice still can be overridden + plugin = currentPlugin; + } else { + if (iface->devices(type).contains(hint.device())) { + plugin = currentPlugin; + break; + } + } + } + } + break; + case QMediaServiceProviderHint::ContentType: { + QtMediaServices::SupportEstimate estimate = QtMediaServices::NotSupported; + foreach (QMediaServiceProviderPlugin *currentPlugin, plugins) { + QtMediaServices::SupportEstimate currentEstimate = QtMediaServices::MaybeSupported; + QMediaServiceSupportedFormatsInterface *iface = + qobject_cast<QMediaServiceSupportedFormatsInterface*>(currentPlugin); + + if (iface) + currentEstimate = iface->hasSupport(hint.mimeType(), hint.codecs()); + + if (currentEstimate > estimate) { + estimate = currentEstimate; + plugin = currentPlugin; + + if (currentEstimate == QtMediaServices::PreferredService) + break; + } + } + } + break; + } + + if (plugin != 0) { + QMediaService *service = plugin->create(key); + if (service != 0) + pluginMap.insert(service, plugin); + + return service; + } + } + + qWarning() << "defaultServiceProvider::requestService(): no service found for -" << key; + return 0; + } + + void releaseService(QMediaService *service) + { + if (service != 0) { + QMediaServiceProviderPlugin *plugin = pluginMap.take(service); + + if (plugin != 0) + plugin->release(service); + } + } + + QtMediaServices::SupportEstimate hasSupport(const QByteArray &serviceType, + const QString &mimeType, + const QStringList& codecs, + int flags) const + { + QList<QObject*> instances = loader()->instances( + QString::fromLatin1(serviceType.constData(),serviceType.length())); + + if (instances.isEmpty()) + return QtMediaServices::NotSupported; + + bool allServicesProvideInterface = true; + QtMediaServices::SupportEstimate supportEstimate = QtMediaServices::NotSupported; + + foreach(QObject *obj, instances) { + QMediaServiceSupportedFormatsInterface *iface = + qobject_cast<QMediaServiceSupportedFormatsInterface*>(obj); + + + if (flags) { + QMediaServiceFeaturesInterface *iface = + qobject_cast<QMediaServiceFeaturesInterface*>(obj); + + if (iface) { + QMediaServiceProviderHint::Features features = iface->supportedFeatures(serviceType); + + //if low latency playback was asked, skip services known + //not to provide low latency playback + if ((flags & QMediaPlayer::LowLatency) && + !(features & QMediaServiceProviderHint::LowLatencyPlayback)) + continue; + + //the same for QIODevice based streams support + if ((flags & QMediaPlayer::StreamPlayback) && + !(features & QMediaServiceProviderHint::StreamPlayback)) + continue; + } + } + + if (iface) + supportEstimate = qMax(supportEstimate, iface->hasSupport(mimeType, codecs)); + else + allServicesProvideInterface = false; + } + + //don't return PreferredService + supportEstimate = qMin(supportEstimate, QtMediaServices::ProbablySupported); + + //Return NotSupported only if no services are available of serviceType + //or all the services returned NotSupported, otherwise return at least MaybeSupported + if (!allServicesProvideInterface) + supportEstimate = qMax(QtMediaServices::MaybeSupported, supportEstimate); + + return supportEstimate; + } + + QStringList supportedMimeTypes(const QByteArray &serviceType, int flags) const + { + QList<QObject*> instances = loader()->instances( + QString::fromLatin1(serviceType.constData(),serviceType.length())); + + QStringList supportedTypes; + + foreach(QObject *obj, instances) { + QMediaServiceSupportedFormatsInterface *iface = + qobject_cast<QMediaServiceSupportedFormatsInterface*>(obj); + + + if (flags & QMediaPlayer::LowLatency) { + QMediaServiceFeaturesInterface *iface = + qobject_cast<QMediaServiceFeaturesInterface*>(obj); + + if (iface) { + QMediaServiceProviderHint::Features features = iface->supportedFeatures(serviceType); + + // If low latency playback was asked for, skip MIME types from services known + // not to provide low latency playback + if ((flags & QMediaPlayer::LowLatency) && + !(features & QMediaServiceProviderHint::LowLatencyPlayback)) + continue; + + //the same for QIODevice based streams support + if ((flags & QMediaPlayer::StreamPlayback) && + !(features & QMediaServiceProviderHint::StreamPlayback)) + continue; + } + } + + if (iface) { + supportedTypes << iface->supportedMimeTypes(); + } + } + + // Multiple services may support the same MIME type + supportedTypes.removeDuplicates(); + + return supportedTypes; + } + + QList<QByteArray> devices(const QByteArray &serviceType) const + { + QList<QByteArray> res; + + foreach(QObject *obj, loader()->instances( + QString::fromLatin1(serviceType.constData(),serviceType.length()))) { + QMediaServiceSupportedDevicesInterface *iface = + qobject_cast<QMediaServiceSupportedDevicesInterface*>(obj); + + if (iface) { + res.append(iface->devices(serviceType)); + } + } + + return res; + } + + QString deviceDescription(const QByteArray &serviceType, const QByteArray &device) + { + foreach(QObject *obj, loader()->instances( + QString::fromLatin1(serviceType.constData(),serviceType.length()))) { + QMediaServiceSupportedDevicesInterface *iface = + qobject_cast<QMediaServiceSupportedDevicesInterface*>(obj); + + if (iface) { + if (iface->devices(serviceType).contains(device)) + return iface->deviceDescription(serviceType, device); + } + } + + return QString(); + } +}; + +Q_GLOBAL_STATIC(QPluginServiceProvider, pluginProvider); + +/*! + \class QMediaServiceProvider + \preliminary + \since 4.7 + \brief The QMediaServiceProvider class provides an abstract allocator for media services. +*/ + +/*! + \fn QMediaServiceProvider::requestService(const QByteArray &type, const QMediaServiceProviderHint &hint) + + Requests an instance of a \a type service which best matches the given \a hint. + + Returns a pointer to the requested service, or a null pointer if there is no suitable service. + + The returned service must be released with releaseService when it is finished with. +*/ + +/*! + \fn QMediaServiceProvider::releaseService(QMediaService *service) + + Releases a media \a service requested with requestService(). +*/ + +/*! + \fn QtMediaServices::SupportEstimate QMediaServiceProvider::hasSupport(const QByteArray &serviceType, const QString &mimeType, const QStringList& codecs, int flags) const + + Returns how confident a media service provider is that is can provide a \a serviceType + service that is able to play media of a specific \a mimeType that is encoded using the listed + \a codecs while adhearing to constraints identified in \a flags. +*/ +QtMediaServices::SupportEstimate QMediaServiceProvider::hasSupport(const QByteArray &serviceType, + const QString &mimeType, + const QStringList& codecs, + int flags) const +{ + Q_UNUSED(serviceType); + Q_UNUSED(mimeType); + Q_UNUSED(codecs); + Q_UNUSED(flags); + + return QtMediaServices::MaybeSupported; +} + +/*! + \fn QStringList QMediaServiceProvider::supportedMimeTypes(const QByteArray &serviceType, int flags) const + + Returns a list of MIME types supported by the service provider for the specified \a serviceType. + + The resultant list is restricted to MIME types which can be supported given the constraints in \a flags. +*/ +QStringList QMediaServiceProvider::supportedMimeTypes(const QByteArray &serviceType, int flags) const +{ + Q_UNUSED(serviceType); + Q_UNUSED(flags); + + return QStringList(); +} + +/*! + Returns the list of devices related to \a service type. +*/ +QList<QByteArray> QMediaServiceProvider::devices(const QByteArray &service) const +{ + Q_UNUSED(service); + return QList<QByteArray>(); +} + +/*! + Returns the description of \a device related to \a serviceType, + suitable to be displayed to user. +*/ +QString QMediaServiceProvider::deviceDescription(const QByteArray &serviceType, const QByteArray &device) +{ + Q_UNUSED(serviceType); + Q_UNUSED(device); + return QString(); +} + + +#ifdef QT_BUILD_INTERNAL + +static QMediaServiceProvider *qt_defaultMediaServiceProvider = 0; + +/*! + Sets a media service \a provider as the default. + + \internal +*/ +void QMediaServiceProvider::setDefaultServiceProvider(QMediaServiceProvider *provider) +{ + qt_defaultMediaServiceProvider = provider; +} + +#endif + +/*! + Returns a default provider of media services. +*/ +QMediaServiceProvider *QMediaServiceProvider::defaultServiceProvider() +{ +#ifdef QT_BUILD_INTERNAL + return qt_defaultMediaServiceProvider != 0 + ? qt_defaultMediaServiceProvider + : static_cast<QMediaServiceProvider *>(pluginProvider()); +#else + return pluginProvider(); +#endif +} + +/*! + \class QMediaServiceProviderPlugin + \preliminary + \since 4.7 + \brief The QMediaServiceProviderPlugin class interface provides an interface for QMediaService + plug-ins. + + A media service provider plug-in may implement one or more of + QMediaServiceSupportedFormatsInterface, QMediaServiceSupportedDevicesInterface, + and QMediaServiceFeaturesInterface to identify the features it supports. +*/ + +/*! + \fn QMediaServiceProviderPlugin::keys() const + + Returns a list of keys for media services a plug-in can create. +*/ + +/*! + \fn QMediaServiceProviderPlugin::create(const QString &key) + + Constructs a new instance of the QMediaService identified by \a key. + + The QMediaService returned must be destroyed with release(). +*/ + +/*! + \fn QMediaServiceProviderPlugin::release(QMediaService *service) + + Destroys a media \a service constructed with create(). +*/ + + +/*! + \class QMediaServiceSupportedFormatsInterface + \brief The QMediaServiceSupportedFormatsInterface class interface + identifies if a media service plug-in supports a media format. + \since 4.7 + + A QMediaServiceProviderPlugin may implement this interface. +*/ + +/*! + \fn QMediaServiceSupportedFormatsInterface::~QMediaServiceSupportedFormatsInterface() + + Destroys a media service supported formats interface. +*/ + +/*! + \fn QMediaServiceSupportedFormatsInterface::hasSupport(const QString &mimeType, const QStringList& codecs) const + + Returns the level of support a media service plug-in has for a \a mimeType and set of \a codecs. +*/ + +/*! + \fn QMediaServiceSupportedFormatsInterface::supportedMimeTypes() const + + Returns a list of MIME types supported by the media service plug-in. +*/ + +/*! + \class QMediaServiceSupportedDevicesInterface + \brief The QMediaServiceSupportedDevicesInterface class interface + identifies the devices supported by a media service plug-in. + \since 4.7 + + A QMediaServiceProviderPlugin may implement this interface. +*/ + +/*! + \fn QMediaServiceSupportedDevicesInterface::~QMediaServiceSupportedDevicesInterface() + + Destroys a media service supported devices interface. +*/ + +/*! + \fn QMediaServiceSupportedDevicesInterface::devices(const QByteArray &service) const + + Returns a list of devices supported by a plug-in \a service. +*/ + +/*! + \fn QMediaServiceSupportedDevicesInterface::deviceDescription(const QByteArray &service, const QByteArray &device) + + Returns a description of a \a device supported by a plug-in \a service. +*/ + +/*! + \class QMediaServiceFeaturesInterface + \brief The QMediaServiceFeaturesInterface class interface identifies + features supported by a media service plug-in. + \since 4.7 + + A QMediaServiceProviderPlugin may implement this interface. +*/ + +/*! + \fn QMediaServiceFeaturesInterface::~QMediaServiceFeaturesInterface() + + Destroys a media service features interface. +*/ +/*! + \fn QMediaServiceFeaturesInterface::supportedFeatures(const QByteArray &service) const + + Returns a set of features supported by a plug-in \a service. +*/ + +QT_END_NAMESPACE + +#include "moc_qmediaserviceprovider.cpp" +#include "moc_qmediaserviceproviderplugin.cpp" |