Phonon.AbstractMediaStream

KDE 4.7 PyKDE API Reference

- KDE's Python API

# AbstractMediaStream Class Reference

`from PyKDE4.phonon import *`

Inherits: QObject
Namespace: Phonon

## Detailed Description

\class AbstractMediaStream abstractmediastream.h phonon/AbstractMediaStream 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>

## Methods
| __init__ (self, QObject parent=0)
| endOfData (self)
| enoughData (self)
| error (self, Phonon::ErrorType errorType, QString errorString)
| needData (self)
| reset (self)
| seekStream (self, long offset)
| setStreamSeekable (self, bool a0)
| setStreamSize (self, long a0)
bool | streamSeekable (self)
long | streamSize (self)
| writeData (self, QByteArray data)

## Method Documentation

__init__ | ( | self, |
|  | QObject | parent=0
| ) |  |  |

Constructs an AbstractMediaStream object with a parent.

endOfData | ( |  | self ) |

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

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

enoughData | ( |  | self ) |

Reimplement this function to be notified when the backend has enough data and your stream object may take a break. This method is important for pushing data to the backend in order to not fill the backend buffer unnecessarily.

error | ( | self, |
|  | Phonon::ErrorType | errorType,
|  | QString | errorString
| ) |  |  |

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

See also:
  MediaObject.errorType()

See also:
  MediaObject.errorString()

needData | ( |  | self ) |

Abstract method:
  This method is abstract and can be overridden but not called directly.

Reimplement this function to be notified when the backend needs data.

When this function is called you should try to call writeData or endOfData before returning.

reset | ( |  | self ) |

Abstract method:
  This method is abstract and can be overridden but not called directly.

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

     seekStream(0);
     \endcode.

seekStream | ( | self, |
|  | long | offset
| ) |  |  |

Reimplement this function if your stream is seekable.

When this function is called the next call to writeData has to be at the requested \p offset.

Warning:
  Do not call the parent implementation.

setStreamSeekable | ( | self, |
|  | bool | a0
| ) |  |  |

Sets whether your data stream is seekable.

Defaults to false.

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

setStreamSize | ( | self, |
|  | long | a0
| ) |  |  |

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 | ( |  | self ) |

Returns whether your data stream is set as seekable.

Defaults to false.

long streamSize | ( |  | self ) |

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.

writeData | ( | self, |
|  | QByteArray | data
| ) |  |  |

Sends the media data to the backend for decoding.

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