The QAudioDecoderControl class provides access to the audio decoding functionality of a QMediaService . 更多...
| 头： | #include <QAudioDecoderControl> |
| qmake: | QT += multimedia |
| 继承： | QMediaControl |
该类在开发且可能改变。
| ~QAudioDecoderControl () | |
| virtual QAudioFormat | audioFormat () const = 0 |
| virtual bool | bufferAvailable () const = 0 |
| virtual qint64 | duration () const = 0 |
| virtual qint64 | position () const = 0 |
| virtual QAudioBuffer | read () = 0 |
| virtual void | setAudioFormat (const QAudioFormat & format ) = 0 |
| virtual void | setSourceDevice (QIODevice * device ) = 0 |
| virtual void | setSourceFilename (const QString & fileName ) = 0 |
| virtual QIODevice * | sourceDevice () const = 0 |
| virtual QString | sourceFilename () const = 0 |
| virtual void | start () = 0 |
| virtual QAudioDecoder::State | state () const = 0 |
| virtual void | stop () = 0 |
| void | bufferAvailableChanged (bool available ) |
| void | bufferReady () |
| void | durationChanged (qint64 duration ) |
| void | error (int error , const QString & errorString ) |
| void | finished () |
| void | formatChanged (const QAudioFormat & format ) |
| void | positionChanged (qint64 position ) |
| void | sourceChanged () |
| void | stateChanged (QAudioDecoder::State state ) |
| QAudioDecoderControl (QObject * parent = Q_NULLPTR) |
| QAudioDecoderControl_iid |
The QAudioDecoderControl class provides access to the audio decoding functionality of a QMediaService .
The functionality provided by this control is exposed to application code through the QAudioDecoder 类。
接口名称对于
QAudioDecoderControl
is
org.qt-project.qt.audiodecodercontrol/5.0
作为定义在
QAudioDecoderControl_iid
.
另请参阅 QMediaService::requestControl () 和 QAudioDecoder .
[protected]
QAudioDecoderControl::
QAudioDecoderControl
(
QObject
*
parent
= Q_NULLPTR)
Constructs a new audio decoder control with the given parent .
Destroys an audio decoder control.
[pure virtual]
QAudioFormat
QAudioDecoderControl::
audioFormat
() const
Returns the current audio format of the decoded stream.
Any buffers returned should have this format.
另请参阅 setAudioFormat () 和 formatChanged ().
[pure virtual]
bool
QAudioDecoderControl::
bufferAvailable
() const
Returns true if a buffer is available to be read, and false otherwise.
[signal]
void
QAudioDecoderControl::
bufferAvailableChanged
(
bool
available
)
信号 bufferAvailable property has changed to available .
[signal]
void
QAudioDecoderControl::
bufferReady
()
Signals that a new buffer is ready for reading.
[pure virtual]
qint64
QAudioDecoderControl::
duration
() const
Returns total duration (in milliseconds) of the audio stream or -1 if not available.
[signal]
void
QAudioDecoderControl::
durationChanged
(
qint64
duration
)
Signals that the estimated duration of the decoded data has changed.
另请参阅 positionChanged ().
[signal]
void
QAudioDecoderControl::
error
(
int
error
, const
QString
&
errorString
)
Signals that an error has occurred. The errorString provides a more detailed explanation.
[signal]
void
QAudioDecoderControl::
finished
()
Signals that the decoding has finished successfully. If decoding fails, error signal is emitted instead.
另请参阅 start (), stop ()，和 error ().
[signal]
void
QAudioDecoderControl::
formatChanged
(const
QAudioFormat
&
format
)
Signals that the current audio format of the decoder has changed to format .
另请参阅 audioFormat () 和 setAudioFormat ().
[pure virtual]
qint64
QAudioDecoderControl::
position
() const
Returns position (in milliseconds) of the last buffer read from the decoder or -1 if no buffers have been read.
[signal]
void
QAudioDecoderControl::
positionChanged
(
qint64
position
)
Signals that the current position of the decoder has changed.
另请参阅 durationChanged ().
[pure virtual]
QAudioBuffer
QAudioDecoderControl::
read
()
Attempts to read a buffer from the decoder, without blocking. Returns invalid buffer if there are no decoded buffers available, or on error.
[pure virtual]
void
QAudioDecoderControl::
setAudioFormat
(const
QAudioFormat
&
format
)
Set the desired audio format for decoded samples to format .
If the decoder does not support this format,
error
() 会被设为
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 .
另请参阅 audioFormat ().
[pure virtual]
void
QAudioDecoderControl::
setSourceDevice
(
QIODevice
*
device
)
Sets the current source to device . Changing the source will stop any current decoding and discard any buffers.
Sources are exclusive, so only one can be set.
另请参阅 sourceDevice ().
[pure virtual]
void
QAudioDecoderControl::
setSourceFilename
(const
QString
&
fileName
)
Sets the current source to fileName . Changing the source will stop any current decoding and discard any buffers.
Sources are exclusive, so only one can be set.
另请参阅 sourceFilename ().
[signal]
void
QAudioDecoderControl::
sourceChanged
()
Signals that the current source of the decoder has changed.
另请参阅 sourceFilename () 和 sourceDevice ().
[pure virtual]
QIODevice
*QAudioDecoderControl::
sourceDevice
() const
Returns the current media source QIODevice , or 0 if none (or a file).
另请参阅 setSourceDevice ().
[pure virtual]
QString
QAudioDecoderControl::
sourceFilename
() const
Returns the current media source filename, or a null QString if none (or a device)
另请参阅 setSourceFilename ().
[pure virtual]
void
QAudioDecoderControl::
start
()
Starts decoding the current media.
If successful the player control will immediately enter the decoding 状态。
[pure virtual]
QAudioDecoder::State
QAudioDecoderControl::
state
() const
Returns the state of a player control.
[signal]
void
QAudioDecoderControl::
stateChanged
(
QAudioDecoder::State
state
)
信号 state of a player control has changed.
另请参阅 state ().
[pure virtual]
void
QAudioDecoderControl::
stop
()
Stops playback of the current media and discards any buffers.
If successful the player control will immediately enter the stopped 状态。
org.qt-project.qt.audiodecodercontrol/5.0
定义接口名为 QAudioDecoderControl 类。