The QAudioDecoder class allows decoding audio. More...

Inheritance diagram for QAudioDecoder:

Public Types
enum	Error

enum	State

Public Signals
void	bufferAvailableChanged (bool available)

void	bufferReady ()

void	durationChanged (qint64 duration)

void	error (QAudioDecoder::Error error)

void	finished ()

void	formatChanged (const QAudioFormat &format)

void	positionChanged (qint64 position)

void	sourceChanged ()

void	stateChanged (QAudioDecoder::State state)

Public Signals inherited from QMediaObject
void	availabilityChanged (bool available)

void	availabilityChanged (QMultimedia::AvailabilityStatus availability)

void	metaDataAvailableChanged (bool available)

void	metaDataChanged ()

void	metaDataChanged (const QString &key, const QVariant &value)

void	notifyIntervalChanged (int milliSeconds)

Public Signals inherited from QObject
void	destroyed (QObject *obj=nullptr)

void	objectNameChanged (const QString &objectName)

Public Slots
void	start ()

void	stop ()

Public Slots inherited from QObject
void	deleteLater ()

Public Methods
	QAudioDecoder (QObject *parent=nullptr)

	~QAudioDecoder ()

QAudioFormat	audioFormat () const

bool	bind (QObject *object) override

bool	bufferAvailable () const

qint64	duration () const

Error	error () const

QString	errorString () const

qint64	position () const

QAudioBuffer	read () const

void	setAudioFormat (const QAudioFormat &format)

void	setSourceDevice (QIODevice *device)

void	setSourceFilename (const QString &fileName)

QIODevice *	sourceDevice () const

QString	sourceFilename () const

State	state () const

void	unbind (QObject *object) override

Public Methods inherited from QMediaObject
	~QMediaObject ()

virtual QMultimedia::AvailabilityStatus	availability () const

QStringList	availableMetaData () const

virtual bool	isAvailable () const

bool	isMetaDataAvailable () const

QVariant	metaData (const QString &key) const

int	notifyInterval () const

virtual QMediaService *	service () const

void	setNotifyInterval (int milliSeconds)

Public Methods inherited from QObject
	QObject (QObject *parent=nullptr)

	~QObject ()

bool	blockSignals (bool block)

const QList< QObject * > &	children () const

bool	connect (const QObject *sender, const QString &signalMethod, const QString &location, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

bool	connect (const QObject *sender, const QString &signalMethod, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

bool	disconnect (const QObject *receiver, const QString &slotMethod=QString ()) const

bool	disconnect (const QString &signalMethod, const QString &location, const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const

bool	disconnect (const QString &signalMethod=QString (), const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const

void	dumpObjectInfo ()

void	dumpObjectTree ()

QList< QString >	dynamicPropertyNames () const

virtual bool	event (QEvent *event)

virtual bool	eventFilter (QObject watched, QEvent event)

template<typename T >
T	findChild (const QString &childName=QString ()) const

template<class T >
QList< T >	findChildren (const QRegularExpression &regExp, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

template<class T >
QList< T >	findChildren (const QString &childName=QString (), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const

bool	inherits (const QString &className) const

void	installEventFilter (QObject *filterObj)

bool	isWidgetType () const

bool	isWindowType () const

void	killTimer (int id)

const QMetaObject *	metaObject () const

void	moveToThread (QThread *targetThread)

QString	objectName () const

QObject *	parent () const

template<class T = QVariant>
T	property (const QString &name) const

void	removeEventFilter (QObject *obj)

void	setObjectName (const QString &name)

void	setParent (QObject *parent)

bool	setProperty (const QString &name, const QVariant &value)

bool	signalsBlocked () const

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)

QThread *	thread () const

Static Public Methods
static QMultimedia::SupportEstimate	hasSupport (const QString &mimeType, const QStringList &codecs=QStringList ())

Static Public Methods inherited from QObject
static bool	connect (const QObject sender, const QMetaMethod &signalMethod, const QObject receiver, const QMetaMethod &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

static bool	connect (const QObject sender, const QString &signalMethod, const QObject receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection, const QString &location=QString ())

static bool	connect (const QObject sender, const QString &signalMethod, const QString &location, const QObject receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool	connect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver receiver, SlotReturn (SlotClass::slotMethod)(SlotArgs...), Qt::ConnectionType type=Qt::AutoConnection)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool	connect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, T slotLambda, Qt::ConnectionType type=Qt::AutoConnection)

static bool	disconnect (const QObject sender, const QMetaMethod &signalMethod, const QObject receiver, const QMetaMethod &slotMethod)

static bool	disconnect (const QObject sender, const QString &signalMethod, const QObject receiver, const QString &slotMethod)

static bool	disconnect (const QObject sender, const QString &signalMethod, const QString &location, const QObject receiver, const QString &slotMethod)

static bool	disconnect (const QObject sender, std::nullptr_t, const QObject receiver, std::nullptr_t)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver receiver, SlotReturn (SlotClass::slotMethod)(SlotArgs...))

template<class Sender , class SignalClass , class... SignalArgs, class Receiver >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, std::nullptr_t slotMethod=nullptr)

template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T >
static bool	disconnect (const Sender sender, void (SignalClass::signalMethod)(SignalArgs...), const Receiver *receiver, T slotMethod)

static QMetaObject &	staticMetaObject ()

static QString	tr (const char text, const char comment=nullptr, std::optional< int > numArg=std::optional< int >())

Properties
	bufferAvailable
	Whether there is a decoded audio buffer available. More...

	error
	String describing the last error condition. More...

	sourceFilename
	Active filename being decoded by the decoder object. More...

	state
	Audio decoder's playback state. More...

Properties inherited from QMediaObject
	notifyInterval

Properties inherited from QObject
	objectName

Additional Inherited Members
Protected Methods inherited from QMediaObject
	QMediaObject (QObject parent, QMediaService service)

template<typename T >
void	addPropertyWatch (const QString &name)

void	removePropertyWatch (const QString &name)

Protected Methods inherited from QObject
virtual void	childEvent (QChildEvent *event)

virtual void	connectNotify (const QMetaMethod &signalMethod) const

virtual void	customEvent (QEvent *event)

virtual void	disconnectNotify (const QMetaMethod &signalMethod) const

bool	isSignalConnected (const QMetaMethod &signalMethod) const

int	receivers (const QString &signal) const

QObject *	sender () const

int	senderSignalIndex () const

virtual void	timerEvent (QTimerEvent *event)

Related Functions inherited from QObject
T	qobject_cast (QObject *object)

	QObjectList

Detailed Description

The QAudioDecoder class is a high level class for decoding local audio media files. It is similar to the QMediaPlayer class except that audio is provided back through this API rather than routed directly to audio hardware, and playlists and network and streaming based media is not supported.

See also: QAudioBuffer

Member Enumeration Documentation

enum QAudioDecoder::Error

Defines a media player error condition.

Constant	Value	Description
`QAudioDecoder::NoError`	0	No error has occurred
`QAudioDecoder::ResourceError`	1	Media resource could not be resolved
`QAudioDecoder::FormatError`	2	Format of a media resource is not supported
`QAudioDecoder::AccessDeniedError`	3	There are not the appropriate permissions to play a media resource
`QAudioDecoder::ServiceMissingError`	4	Valid playback service was not found, playback cannot proceed

enum QAudioDecoder::State

Defines the current state of a media player.

Constant	Value	Description
`QAudioDecoder::StoppedState`	0	Decoder is not decoding, will start at the beginning of the media
`QAudioDecoder::DecodingState`	1	Audio player is currently decoding media

Constructor & Destructor Documentation

QAudioDecoder::QAudioDecoder ( QObject * parent = nullptr )

explicit

Construct an QAudioDecoder instance parented to parent.

QAudioDecoder::~QAudioDecoder ( )

Destroys the audio decoder object.

Method Documentation

QAudioFormat QAudioDecoder::audioFormat ( ) const

Returns the current audio format of the decoded stream. Any buffers returned should have this format.

See also: setAudioFormat(), formatChanged()

bool QAudioDecoder::bind ( QObject * object )

overridevirtual

Bind object to this QMediaObject instance. This method establishes a relationship between this media object and a helper object. The nature of the relationship depends on both parties. This methods returns true if the helper was successfully bound, false otherwise.

Most subclasses of QMediaObject provide more convenient functions that wrap this functionality so this function rarely needs to be called directly.

The object passed must implement the QMediaBindableInterface interface.

See also: QMediaBindableInterface

Reimplemented from QMediaObject::bind()

bool QAudioDecoder::bufferAvailable ( ) const

Returns true if a buffer is available to be read, and false otherwise. If there is no buffer available, calling read() will return an invalid buffer.

void QAudioDecoder::bufferAvailableChanged ( bool available )

signal

Signals the availability (if available is true) of a new buffer. If available is false, there are no buffers available.

See also: bufferAvailable(), bufferReady()

void QAudioDecoder::bufferReady ( )

signal

Signals a new decoded audio buffer is available to be read.

See also: read(), bufferAvailable()

qint64 QAudioDecoder::duration ( ) const

Returns total duration (in milliseconds) of the audio stream or -1 if not available.

void QAudioDecoder::durationChanged ( qint64 duration )

signal

Signals the estimated duration of the decoded data has changed.

See also: positionChanged()

QAudioDecoder::Error QAudioDecoder::error ( ) const

Returns the current error state.

void QAudioDecoder::error ( QAudioDecoder::Error error )

signal

Signals an error condition has occurred.

See also: errorString()

QString QAudioDecoder::errorString ( ) const

Return the value of the error property.

void QAudioDecoder::finished ( )

signal

Signals the decoding has finished successfully. If decoding fails, error signal is emitted instead.

See also: start(), stop(), error()

void QAudioDecoder::formatChanged ( const QAudioFormat & format )

signal

Signals the current audio format of the decoder has changed to format.

See also: audioFormat(), setAudioFormat()

QMultimedia::SupportEstimate QAudioDecoder::hasSupport	(	const QString &	mimeType,
		const QStringList &	codecs = `QStringList()`
	)

static

Returns the level of support an audio decoder has for a mimeType and a set of codecs.

qint64 QAudioDecoder::position ( ) const

Returns position (in milliseconds) of the last buffer read from the decoder or -1 if no buffers have been read.

void QAudioDecoder::positionChanged ( qint64 position )

signal

Signals the current position of the decoder has changed.

See also: durationChanged()

QAudioBuffer QAudioDecoder::read ( ) const

Read a buffer from the decoder, if one is available. Returns an invalid buffer if there are no decoded buffers currently available, or on failure. In both cases this function will not block.

You should either respond to the bufferReady() signal or check the bufferAvailable() methods before calling read() to make sure you get useful data.

void QAudioDecoder::setAudioFormat ( const QAudioFormat & format )

Set the desired audio format for decoded samples to format. This property can only be set while the decoder is stopped. Setting this property at other times will be ignored.

If the decoder does not support this format, error() will be set to FormatError. If you do not specify a format, the format of the decoded audio itself will be used. Otherwise, some format conversion will be applied.

If you wish to reset the decoded format to that of the original audio file, you can specify an invalid format.

void QAudioDecoder::setSourceDevice ( QIODevice * device )

Sets the current audio QIODevice to device. When this property is set any current decoding is stopped, and any audio buffers are discarded.

You can only specify either a source filename or a source QIODevice. Setting one will unset the other.

void QAudioDecoder::setSourceFilename ( const QString & fileName )

Sets the current audio file name to fileName. When this property is set any current decoding is stopped, and any audio buffers are discarded.

You can only specify either a source filename or a source QIODevice. Setting one will unset the other.

void QAudioDecoder::sourceChanged ( )

signal

Signals the current source of the decoder has changed.

See also: sourceFilename(), sourceDevice()

QIODevice * QAudioDecoder::sourceDevice ( ) const

Returns the current source QIODevice, if one was set. If setSourceFilename() was called, this will be 0.

QString QAudioDecoder::sourceFilename ( ) const

Returns the current file name to decode. If setSourceDevice() was called there is no file name so the return value will be an empty string.

void QAudioDecoder::start ( )

slot

Starts decoding the audio resource.

As data gets decoded, the bufferReady() signal will be emitted when enough data has been decoded. Calling read() will then return an audio buffer without blocking. If you call read() before a buffer is ready, an invalid buffer will be returned, again without blocking.

See also: read()

State QAudioDecoder::state ( ) const

Returns the audio decoder's playback state.

void QAudioDecoder::stateChanged ( QAudioDecoder::State state )

signal

Signal the state of the decoder object has changed.

void QAudioDecoder::stop ( )

slot

Stop decoding audio. Calling start() again will resume decoding from the beginning.

void QAudioDecoder::unbind ( QObject * object )

overridevirtual

Detach object from the QMediaObject instance. Unbind the helper object from this media object. A warning will be generated if the object was not previously bound to this object.

See also: QMediaBindableInterface

Reimplemented from QMediaObject::unbind()

Property Documentation

QAudioDecoder::bufferAvailable

This property stores whether there is a decoded audio buffer available.

Properties	Class Methods
read	bufferAvailable
notify	bufferAvailableChanged

QAudioDecoder::error

This property stores a string describing the last error condition.

See also: error()

Properties	Class Methods
read	errorString

QAudioDecoder::sourceFilename

This property stores the active filename being decoded by the decoder object.

Properties	Class Methods
read	sourceFilename
write	setSourceFilename
notify	sourceChanged

QAudioDecoder::state

This property stores the audio decoder's playback state. By default this property is QAudioDecoder::Stopped

See also: start(), stop()

Properties	Class Methods
read	state
notify	stateChanged

Public Types

Public Signals

Public Slots

Public Methods

Static Public Methods

Properties

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Method Documentation

Property Documentation