Detailed Description

Base class for custom media data streams.

Implement this class to provide a custom data stream to the backend. The class supports both, the push and the pull model.

Push:

 PushStream::PushStream(QObject *parent)
   : AbstractMediaStream(parent), m_timer(new QTimer(this))
 {
   setStreamSize(getMediaStreamSize());

   connect(m_timer, SIGNAL(timeout()), SLOT(moreData()));
   m_timer->setInterval(0);
 }

 void PushStream::moreData()
 {
   const QByteArray data = getMediaData();
   if (data.isEmpty()) {
     endOfData();
   } else {
     writeData(data);
   }
 }

 void PushStream::needData()
 {
   m_timer->start();
   moreData();
 }

 void PushStream::enoughData()
 {
   m_timer->stop();
 }

Pull:

 PullStream::PullStream(QObject *parent)
   : AbstractMediaStream(parent)
 {
   setStreamSize(getMediaStreamSize());
 }

 void PullStream::needData()
 {
   const QByteArray data = getMediaData();
   if (data.isEmpty()) {
     endOfData();
   } else {
     writeData(data);
   }
 }

Author:: Matthias Kretz <kretz@kde.org>

Definition at line 103 of file abstractmediastream.h.

#include <Phonon/AbstractMediaStream>

Inheritance diagram for AbstractMediaStream:

[legend]

List of all members.

Public Member Functions
virtual	~AbstractMediaStream ()
Protected Member Functions
	AbstractMediaStream (QObject *parent=0)
	Constructs an AbstractMediaStream object with a `parent`.
qint64	streamSize () const
	Returns the stream size that was set with setStreamSize.
void	setStreamSize (qint64)
	Sets the size of the stream in number of bytes.
bool	streamSeekable () const
	Returns whether your data stream is set as seekable.
void	setStreamSeekable (bool)
	Sets whether your data stream is seekable.
void	writeData (const QByteArray &data)
	Sends the media `data` to the backend for decoding.
void	endOfData ()
	Tells the backend that the media data stream is at its end.
void	error (Phonon::ErrorType errorType, const QString &errorString)
	If an I/O error occurs you should call this function to make MediaObject go into ErrorState.
virtual void	reset ()=0
	Reimplement this function to reset the stream.
virtual void	needData ()=0
	Reimplement this function to be notified when the backend needs data.
virtual void	enoughData ()
	Reimplement this function to be notified when the backend has enough data and your stream object may take a break.
virtual void	seekStream (qint64 offset)
	Reimplement this function if your stream is seekable.
	AbstractMediaStream (AbstractMediaStreamPrivate &dd, QObject *parent)
Protected Attributes
QScopedPointer < AbstractMediaStreamPrivate >	d_ptr
Friends
class	MediaObject
class	MediaObjectPrivate
class	StreamInterface

Constructor & Destructor Documentation

virtual ~AbstractMediaStream ( ) [virtual]

AbstractMediaStream ( QObject * parent = 0 ) [explicit, protected]

Constructs an AbstractMediaStream object with a parent.

AbstractMediaStream	(	AbstractMediaStreamPrivate &	dd,
		QObject *	parent
	)		`[protected]`

Member Function Documentation

qint64 streamSize ( ) const [protected]

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Returns the stream size that was set with setStreamSize.

A negative value means that the length of the stream cannot be known.

Defaults to 0.

void setStreamSize ( qint64 ) [protected]

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Sets the size of the stream in number of bytes.

A negative value means that the length of the stream cannot be known.

Defaults to 0.

This function has to be called. A backend will not call needData() until the stream size is set.

bool streamSeekable ( ) const [protected]

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Returns whether your data stream is set as seekable.

Defaults to false.

void setStreamSeekable ( bool ) [protected]

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Sets whether your data stream is seekable.

Defaults to false.

If you set this to true you have to implement the seekStream function.

void writeData ( const QByteArray & data ) [protected]

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Sends the media data to the backend for decoding.

Warning:: Don't call this function before the first needData() is emitted.

void endOfData ( ) [protected]

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Tells the backend that the media data stream is at its end.

Warning:: Don't call this function before the first needData() is emitted.

void error	(	Phonon::ErrorType	errorType,
		const QString &	errorString
	)		`[protected]`

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If an I/O error occurs you should call this function to make MediaObject go into ErrorState.

See also:: MediaObject::errorType(); MediaObject::errorString()

virtual void reset ( ) [protected, pure virtual]

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Reimplement this function to reset the stream.

Subsequent calls to writeData should start from the first position of the data unless a seek is requested.

The function is necessary for the case where a non-seekable MediaStream is played more than once. For a seekable stream the implementation can simply call