内容

公共类型
特性
公共函数
重实现公共函数
公共槽
信号
详细描述

QMediaRecorder 类

QMediaRecorder class is used for the recording of media content. 更多...

头：	#include <QMediaRecorder>
qmake:	QT += multimedia
继承：	QObject and QMediaBindableInterface
继承者：	QAudioRecorder

所有成员列表，包括继承成员

公共类型

enum	Error { NoError, ResourceError, FormatError, OutOfSpaceError }
enum	State { StoppedState, RecordingState, PausedState }
enum	Status { UnavailableStatus, UnloadedStatus, LoadingStatus, LoadedStatus, ..., FinalizingStatus }

特性

actualLocation : const QUrl
duration : const qint64
metaDataAvailable : const bool
metaDataWritable : const bool
muted : bool

outputLocation : QUrl
state : const QMediaRecorder::State
status : const QMediaRecorder::Status
volume : qreal

1 特性继承自 QObject

公共函数

	QMediaRecorder (QMediaObject * mediaObject , QObject * parent = Q_NULLPTR)
	~QMediaRecorder ()
QUrl	actualLocation () const
QString	audioCodecDescription (const QString & codec ) const
QAudioEncoderSettings	audioSettings () const
QMultimedia::AvailabilityStatus	availability () const
QStringList	availableMetaData () const
QString	containerDescription (const QString & format ) const
QString	containerFormat () const
qint64	duration () const
Error	error () const
QString	errorString () const
bool	isAvailable () const
bool	isMetaDataAvailable () const
bool	isMetaDataWritable () const
bool	isMuted () const
QVariant	metaData (const QString & key ) const
QUrl	outputLocation () const
void	setAudioSettings (const QAudioEncoderSettings & settings )
void	setContainerFormat (const QString & container )
void	setEncodingSettings (const QAudioEncoderSettings & audio , const QVideoEncoderSettings & video = QVideoEncoderSettings(), const QString & container = QString())
void	setMetaData (const QString & key , const QVariant & value )
bool	setOutputLocation (const QUrl & location )
void	setVideoSettings (const QVideoEncoderSettings & settings )
State	state () const
Status	status () const
QStringList	supportedAudioCodecs () const
QList<int>	supportedAudioSampleRates (const QAudioEncoderSettings & settings = QAudioEncoderSettings(), bool * continuous = Q_NULLPTR) const
QStringList	supportedContainers () const
QList<qreal>	supportedFrameRates (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const
QList<QSize>	supportedResolutions (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const
QStringList	supportedVideoCodecs () const
QString	videoCodecDescription (const QString & codec ) const
QVideoEncoderSettings	videoSettings () const
qreal	volume () const

重实现公共函数

virtual QMediaObject *

mediaObject () const override

32 公共函数继承自 QObject
1 公共函数继承自 QMediaBindableInterface

公共槽

void	pause ()
void	record ()
void	setMuted (bool muted )
void	setVolume (qreal volume )
void	stop ()

1 公共槽继承自 QObject

信号

void	actualLocationChanged (const QUrl & location )
void	availabilityChanged (bool available )
void	availabilityChanged (QMultimedia::AvailabilityStatus availability )
void	durationChanged (qint64 duration )
void	error (QMediaRecorder::Error error )
void	metaDataAvailableChanged (bool available )
void	metaDataChanged ()
void	metaDataChanged (const QString & key , const QVariant & value )
void	metaDataWritableChanged (bool writable )
void	mutedChanged (bool muted )
void	stateChanged (QMediaRecorder::State state )
void	statusChanged (QMediaRecorder::Status status )
void	volumeChanged (qreal volume )

2 信号继承自 QObject

额外继承成员

11 静态公共成员继承自 QObject
9 保护函数继承自 QObject
1 保护函数继承自 QMediaBindableInterface

详细描述

QMediaRecorder class is used for the recording of media content.

QMediaRecorder class is a high level media recording class. It's not intended to be used alone but for accessing the media recording functions of other media objects, like QRadioTuner ，或 QCamera .

recorder = new QMediaRecorder(camera);
QAudioEncoderSettings audioSettings;
audioSettings.setCodec("audio/amr");
audioSettings.setQuality(QMultimedia::HighQuality);
recorder->setAudioSettings(audioSettings);
recorder->setOutputLocation(QUrl::fromLocalFile(fileName));
recorder->record();

另请参阅 QAudioRecorder .

成员类型文档编制

enum QMediaRecorder:: Error

常量	值	描述
`QMediaRecorder::NoError`	`0`	没有错误。
`QMediaRecorder::ResourceError`	`1`	Device is not ready or not available.
`QMediaRecorder::FormatError`	`2`	Current format is not supported.
`QMediaRecorder::OutOfSpaceError`	`3`	No space left on device.

enum QMediaRecorder:: State

常量	值	描述
`QMediaRecorder::StoppedState`	`0`	The recorder is not active. If this is the state after recording then the actual created recording has finished being written to the final location and is ready on all platforms except on Android. On Android, due to platform limitations, there is no way to be certain that the recording has finished writing to the final location.
`QMediaRecorder::RecordingState`	`1`	The recording is requested.
`QMediaRecorder::PausedState`	`2`	The recorder is paused.

enum QMediaRecorder:: Status

常量	值	描述
`QMediaRecorder::UnavailableStatus`	`0`	The recorder is not available or not supported by connected media object.
`QMediaRecorder::UnloadedStatus`	`1`	The recorder is avilable but not loaded.
`QMediaRecorder::LoadingStatus`	`2`	The recorder is initializing.
`QMediaRecorder::LoadedStatus`	`3`	The recorder is initialized and ready to record media.
`QMediaRecorder::StartingStatus`	`4`	Recording is requested but not active yet.
`QMediaRecorder::RecordingStatus`	`5`	Recording is active.
`QMediaRecorder::PausedStatus`	`6`	Recording is paused.
`QMediaRecorder::FinalizingStatus`	`7`	Recording is stopped with media being finalized.

特性文档编制

actualLocation : const QUrl

This property holds the actual location of the last media content.

The actual location is usually available after recording starts, and reset when new location is set or new recording starts.

访问函数：

QUrl	actualLocation () const

通知程序信号：

void	actualLocationChanged (const QUrl & location )

duration : const qint64

This property holds the recorded media duration in milliseconds.

访问函数：

qint64 duration () const

通知程序信号：

void	durationChanged (qint64 duration )

metaDataAvailable : const bool

This property holds whether access to a media object's meta-data is available.

If this is true there is meta-data available, otherwise there is no meta-data available.

访问函数：

bool	isMetaDataAvailable () const

通知程序信号：

void	metaDataAvailableChanged (bool available )

metaDataWritable : const bool

This property holds whether a media object's meta-data is writable.

If this is true the meta-data is writable, otherwise the meta-data is read-only.

访问函数：

bool	isMetaDataWritable () const

通知程序信号：

void	metaDataWritableChanged (bool writable )

muted : bool

This property holds whether a recording audio stream is muted.

访问函数：

bool	isMuted () const
void	setMuted (bool muted )

通知程序信号：

void	mutedChanged (bool muted )

outputLocation : QUrl

This property holds the destination location of media content.

Setting the location can fail, for example when the service supports only local file system locations but a network URL was passed. If the service does not support media recording this setting the output location will always fail.

location can be relative or empty; in this case the recorder uses the system specific place and file naming scheme. After recording has stated, QMediaRecorder::outputLocation() returns the actual output location.

访问函数：

QUrl	outputLocation () const
bool	setOutputLocation (const QUrl & location )

state : const QMediaRecorder::State

This property holds the current state of the media recorder.

The state property represents the user request and is changed synchronously during record (), pause () 或 stop () calls. Recorder state may also change asynchronously when recording fails.

访问函数：

State state () const

通知程序信号：

void	stateChanged (QMediaRecorder::State state )

status : const QMediaRecorder::Status

This property holds the current status of the media recorder.

The status is changed asynchronously and represents the actual status of media recorder.

访问函数：

Status status () const

通知程序信号：

void	statusChanged (QMediaRecorder::Status status )

volume : qreal

This property holds the current recording audio volume.

The volume is scaled linearly from 0.0 (silence) to 1.0 (full volume). Values outside this range will be clamped.

默认音量为 1.0 .

UI volume controls should usually be scaled nonlinearly. For example, using a logarithmic scale will produce linear changes in perceived loudness, which is what a user would normally expect from a volume control. See QAudio::convertVolume () 了解更多细节。

访问函数：

qreal	volume () const
void	setVolume (qreal volume )

通知程序信号：

void	volumeChanged (qreal volume )

成员函数文档编制

QMediaRecorder:: QMediaRecorder ( QMediaObject * mediaObject , QObject * parent = Q_NULLPTR)

Constructs a media recorder which records the media produced by mediaObject .

parent 会被传递给 QMediaObject .

QMediaRecorder:: ~QMediaRecorder ()

Destroys a media recorder object.

`[signal]` void QMediaRecorder:: actualLocationChanged (const QUrl & location )

Signals that the actual location of the recorded media has changed. This signal is usually emitted when recording starts.

注意： 通知程序信号对于特性 actualLocation .

QString QMediaRecorder:: audioCodecDescription (const QString & codec ) const

Returns a description of an audio codec .

QAudioEncoderSettings QMediaRecorder:: audioSettings () const

Returns the audio encoder settings being used.

另请参阅 setAudioSettings () 和 setEncodingSettings ().

QMultimedia::AvailabilityStatus QMediaRecorder:: availability () const

Returns the availability of this functionality.

另请参阅 availabilityChanged ().

`[signal]` void QMediaRecorder:: availabilityChanged ( bool available )

Signals that the media recorder is now available (if available is true), or not.

注意： 信号 availabilityChanged 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示：

connect(mediaRecorder, static_cast<void(QMediaRecorder::*)(bool)>(&QMediaRecorder::availabilityChanged),
    [=](bool available){ /* ... */ });

`[signal]` void QMediaRecorder:: availabilityChanged ( QMultimedia::AvailabilityStatus availability )

Signals that the service availability has changed to availability .

注意： 信号 availabilityChanged 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示：

connect(mediaRecorder, static_cast<void(QMediaRecorder::*)(QMultimedia::AvailabilityStatus)>(&QMediaRecorder::availabilityChanged),
    [=](QMultimedia::AvailabilityStatus availability){ /* ... */ });

QStringList QMediaRecorder:: availableMetaData () const

返回元数据的可用键列表。

QString QMediaRecorder:: containerDescription (const QString & format ) const

Returns a description of a container format .

QString QMediaRecorder:: containerFormat () const

Returns the selected container format.

另请参阅 setContainerFormat ().

`[signal]` void QMediaRecorder:: durationChanged ( qint64 duration )

信号 duration of the recorded media has changed.

注意： 通知程序信号对于特性 duration .

Error QMediaRecorder:: error () const

返回当前错误状态。

另请参阅 errorString ().

`[signal]` void QMediaRecorder:: error ( QMediaRecorder::Error error )

Signals that an error has occurred.

注意： 信号 error 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示：

connect(mediaRecorder, static_cast<void(QMediaRecorder::*)(QMediaRecorder::Error)>(&QMediaRecorder::error),
    [=](QMediaRecorder::Error error){ /* ... */ });

QString QMediaRecorder:: errorString () const

Returns a string describing the current error state.

另请参阅 error ().

bool QMediaRecorder:: isAvailable () const

Returns true if media recorder service ready to use.

另请参阅 availabilityChanged ().

`[override virtual]` QMediaObject *QMediaRecorder:: mediaObject () const

重实现自 QMediaBindableInterface::mediaObject ().

返回 QMediaObject instance that this QMediaRecorder is bound too, or 0 otherwise.

QVariant QMediaRecorder:: metaData (const QString & key ) const

返回的值关联元数据 key .

另请参阅 setMetaData ().

`[signal]` void QMediaRecorder:: metaDataAvailableChanged ( bool available )

信号 available state of a media object's meta-data has changed.

注意： 通知程序信号对于特性 metaDataAvailable .

`[signal]` void QMediaRecorder:: metaDataChanged ()

Signals that a media object's meta-data has changed.

If multiple meta-data elements are changed, metaDataChanged(const QString &key, const QVariant &value) signal is emitted for each of them with metaDataChanged() changed emitted once.

注意： 信号 metaDataChanged 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示：

connect(mediaRecorder, static_cast<void(QMediaRecorder::*)()>(&QMediaRecorder::metaDataChanged),
    [=](){ /* ... */ });

`[signal]` void QMediaRecorder:: metaDataChanged (const QString & key , const QVariant & value )

Signal the changes of one meta-data element value 采用给定 key .

注意： 信号 metaDataChanged 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示：

connect(mediaRecorder, static_cast<void(QMediaRecorder::*)(const QString &, const QVariant &)>(&QMediaRecorder::metaDataChanged),
    [=](const QString &key, const QVariant &value){ /* ... */ });

`[signal]` void QMediaRecorder:: metaDataWritableChanged ( bool writable )

信号 writable state of a media object's meta-data has changed.

注意： 通知程序信号对于特性 metaDataWritable .

`[signal]` void QMediaRecorder:: mutedChanged ( bool muted )

信号 muted state has changed. If true the recording is being muted.

注意： 通知程序信号对于特性 muted .

`[slot]` void QMediaRecorder:: pause ()

Pause recording.

The recorder state is changed to QMediaRecorder::PausedState .

Depending on platform recording pause may be not supported, in this case the recorder state stays unchanged.

`[slot]` void QMediaRecorder:: record ()

开始录制。

While the recorder state is changed immediately to QMediaRecorder::RecordingState , recording may start asynchronously, with statusChanged ( QMediaRecorder::RecordingStatus ) signal emitted when recording starts.

If recording fails error () signal is emitted with recorder state being reset back to QMediaRecorder::StoppedState .

void QMediaRecorder:: setAudioSettings (const QAudioEncoderSettings & settings )

Sets the audio encoder settings .

If some parameters are not specified, or null settings are passed, the encoder will choose default encoding parameters, depending on media source properties.

It's only possible to change settings when the encoder is in the QMediaEncoder::StoppedState state.

另请参阅 audioSettings (), videoSettings ()，和 containerFormat ().

void QMediaRecorder:: setContainerFormat (const QString & container )

Sets the media container 格式。

If the container format is not specified, the encoder will choose format, depending on media source properties and encoding settings selected.

It's only possible to change settings when the encoder is in the QMediaEncoder::StoppedState state.

另请参阅 audioSettings (), videoSettings ()，和 containerFormat ().

void QMediaRecorder:: setEncodingSettings (const QAudioEncoderSettings & audio , const QVideoEncoderSettings & video = QVideoEncoderSettings(), const QString & container = QString())

设置 audio and video encoder settings and container 格式。

If some parameters are not specified, or null settings are passed, the encoder will choose default encoding parameters, depending on media source properties.

It's only possible to change settings when the encoder is in the QMediaEncoder::StoppedState state.

另请参阅 audioSettings (), videoSettings ()，和 containerFormat ().

void QMediaRecorder:: setMetaData (const QString & key , const QVariant & value )

设置 value for a meta-data key .

注意： To ensure that meta data is set corretly, it should be set before starting the recording. Once the recording is stopped, any meta data set will be attached to the next recording.

另请参阅 metaData ().

void QMediaRecorder:: setVideoSettings (const QVideoEncoderSettings & settings )

Sets the video encoder settings .

If some parameters are not specified, or null settings are passed, the encoder will choose default encoding parameters, depending on media source properties.

It's only possible to change settings when the encoder is in the QMediaEncoder::StoppedState state.

另请参阅 audioSettings (), videoSettings ()，和 containerFormat ().

State QMediaRecorder:: state () const

Returns the current media recorder state.

注意： Getter 函数对于特性 state .

另请参阅 QMediaRecorder::State .

`[signal]` void QMediaRecorder:: stateChanged ( QMediaRecorder::State state )

Signals that a media recorder's state 已改变。

注意： 通知程序信号对于特性 state .

Status QMediaRecorder:: status () const

Returns the current media recorder status.

注意： Getter 函数对于特性 status .

另请参阅 QMediaRecorder::Status .

`[slot]` void QMediaRecorder:: stop ()

Stop recording.

The recorder state is changed to QMediaRecorder::StoppedState .

QStringList QMediaRecorder:: supportedAudioCodecs () const

Returns a list of supported audio codecs.

QList < int > QMediaRecorder:: supportedAudioSampleRates (const QAudioEncoderSettings & settings = QAudioEncoderSettings(), bool * continuous = Q_NULLPTR) const

Returns a list of supported audio sample rates.

If non null audio settings parameter is passed, the returned list is reduced to sample rates supported with partial settings applied.

This can be used to query the list of sample rates, supported by specific audio codec.

If the encoder supports arbitrary sample rates within the supported rates range, * continuous is set to true, otherwise * continuous 被设为 false。

QStringList QMediaRecorder:: supportedContainers () const

Returns a list of supported container formats.

QList < qreal > QMediaRecorder:: supportedFrameRates (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const

Returns a list of frame rates video can be encoded at.

If non null video settings parameter is passed, the returned list is reduced to frame rates supported with partial settings like video codec or resolution applied.

If the encoder supports arbitrary frame rates within the supported range, * continuous is set to true, otherwise * continuous 被设为 false。

另请参阅 QVideoEncoderSettings::frameRate ().

QList < QSize > QMediaRecorder:: supportedResolutions (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const

Returns a list of resolutions video can be encoded at.

If non null video settings parameter is passed, the returned list is reduced to resolution supported with partial settings like video codec or framerate applied.

If the encoder supports arbitrary resolutions within the supported range, * continuous is set to true, otherwise * continuous 被设为 false。

另请参阅 QVideoEncoderSettings::resolution ().

QStringList QMediaRecorder:: supportedVideoCodecs () const

Returns a list of supported video codecs.

QString QMediaRecorder:: videoCodecDescription (const QString & codec ) const

Returns a description of a video codec .

另请参阅 setEncodingSettings ().

QVideoEncoderSettings QMediaRecorder:: videoSettings () const

Returns the video encoder settings being used.

另请参阅 setVideoSettings () 和 setEncodingSettings ().

内容

QMediaRecorder 类

公共类型

特性

公共函数

重实现公共函数

公共槽

信号

额外继承成员

详细描述

成员类型文档编制

enum QMediaRecorder:: Error

enum QMediaRecorder:: State

enum QMediaRecorder:: Status

特性文档编制

actualLocation : const QUrl

duration : const qint64

metaDataAvailable : const bool

metaDataWritable : const bool

muted : bool

outputLocation : QUrl

state : const QMediaRecorder::State

status : const QMediaRecorder::Status

volume : qreal

成员函数文档编制

QMediaRecorder:: QMediaRecorder ( QMediaObject * mediaObject , QObject * parent = Q_NULLPTR)

QMediaRecorder:: ~QMediaRecorder ()

[signal] void QMediaRecorder:: actualLocationChanged (const QUrl & location )

QString QMediaRecorder:: audioCodecDescription (const QString & codec ) const

QAudioEncoderSettings QMediaRecorder:: audioSettings () const

QMultimedia::AvailabilityStatus QMediaRecorder:: availability () const

[signal] void QMediaRecorder:: availabilityChanged ( bool available )

[signal] void QMediaRecorder:: availabilityChanged ( QMultimedia::AvailabilityStatus availability )

QStringList QMediaRecorder:: availableMetaData () const

QString QMediaRecorder:: containerDescription (const QString & format ) const

QString QMediaRecorder:: containerFormat () const

[signal] void QMediaRecorder:: durationChanged ( qint64 duration )

Error QMediaRecorder:: error () const

[signal] void QMediaRecorder:: error ( QMediaRecorder::Error error )

QString QMediaRecorder:: errorString () const

bool QMediaRecorder:: isAvailable () const

[override virtual] QMediaObject *QMediaRecorder:: mediaObject () const

QVariant QMediaRecorder:: metaData (const QString & key ) const

[signal] void QMediaRecorder:: metaDataAvailableChanged ( bool available )

[signal] void QMediaRecorder:: metaDataChanged ()

[signal] void QMediaRecorder:: metaDataChanged (const QString & key , const QVariant & value )

[signal] void QMediaRecorder:: metaDataWritableChanged ( bool writable )

[signal] void QMediaRecorder:: mutedChanged ( bool muted )

[slot] void QMediaRecorder:: pause ()

[slot] void QMediaRecorder:: record ()

void QMediaRecorder:: setAudioSettings (const QAudioEncoderSettings & settings )

void QMediaRecorder:: setContainerFormat (const QString & container )

void QMediaRecorder:: setEncodingSettings (const QAudioEncoderSettings & audio , const QVideoEncoderSettings & video = QVideoEncoderSettings(), const QString & container = QString())

void QMediaRecorder:: setMetaData (const QString & key , const QVariant & value )

void QMediaRecorder:: setVideoSettings (const QVideoEncoderSettings & settings )

State QMediaRecorder:: state () const

[signal] void QMediaRecorder:: stateChanged ( QMediaRecorder::State state )

Status QMediaRecorder:: status () const

[slot] void QMediaRecorder:: stop ()

QStringList QMediaRecorder:: supportedAudioCodecs () const

QList < int > QMediaRecorder:: supportedAudioSampleRates (const QAudioEncoderSettings & settings = QAudioEncoderSettings(), bool * continuous = Q_NULLPTR) const

QStringList QMediaRecorder:: supportedContainers () const

QList < qreal > QMediaRecorder:: supportedFrameRates (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const

QList < QSize > QMediaRecorder:: supportedResolutions (const QVideoEncoderSettings & settings = QVideoEncoderSettings(), bool * continuous = Q_NULLPTR) const

QStringList QMediaRecorder:: supportedVideoCodecs () const

QString QMediaRecorder:: videoCodecDescription (const QString & codec ) const

QVideoEncoderSettings QMediaRecorder:: videoSettings () const

`[signal]` void QMediaRecorder:: actualLocationChanged (const QUrl & location )

`[signal]` void QMediaRecorder:: availabilityChanged ( bool available )

`[signal]` void QMediaRecorder:: availabilityChanged ( QMultimedia::AvailabilityStatus availability )

`[signal]` void QMediaRecorder:: durationChanged ( qint64 duration )

`[signal]` void QMediaRecorder:: error ( QMediaRecorder::Error error )

`[override virtual]` QMediaObject *QMediaRecorder:: mediaObject () const

`[signal]` void QMediaRecorder:: metaDataAvailableChanged ( bool available )

`[signal]` void QMediaRecorder:: metaDataChanged ()

`[signal]` void QMediaRecorder:: metaDataChanged (const QString & key , const QVariant & value )

`[signal]` void QMediaRecorder:: metaDataWritableChanged ( bool writable )

`[signal]` void QMediaRecorder:: mutedChanged ( bool muted )

`[slot]` void QMediaRecorder:: pause ()

`[slot]` void QMediaRecorder:: record ()

`[signal]` void QMediaRecorder:: stateChanged ( QMediaRecorder::State state )

`[slot]` void QMediaRecorder:: stop ()