CSourcePosition Class

CSourcePosition is an abstract class that assists source filters with the implementation of IMediaPosition methods.

Derive from this class and set the duration and default stop positions. This class supports IMediaPosition, and calls the pure virtual member functions CSourcePosition::ChangeStart, CSourcePosition::ChangeStop, and CSourcePosition::ChangeRate when CSourcePosition::put_CurrentPosition, CSourcePosition::put_StopTime, or CSourcePosition::put_Rate is called, to allow a source filter to handle these commands and start sending new data.

Override the CSourcePosition::ChangeStart, CSourcePosition::ChangeStop, and CSourcePosition::ChangeRate member functions to do something when the properties change.

Protected Data Members

m_Duration Duration of the stream.
m_pLock Pointer to a CCritSec object for locking.
m_Rate Sample rate.
m_Start Start time.
m_Stop Stop time.

Member Functions

CSourcePosition Constructs a CSourcePosition object.

Overridable Member Functions

ChangeRate Override this pure virtual to handle notification that the rate property has changed.
ChangeStart Override this pure virtual to handle notification that the start position property has changed.
ChangeStop Override this pure virtual to handle notification that the stop position property has changed.

Implemented IMediaPosition Methods

get_CurrentPosition Not currently implemented.
get_Duration Retrieves the total duration of the media.
get_PrerollTime Not currently implemented.
get_Rate Retrieves the playback rate, relative to normal playback of the media.
get_StopTime Retrieves the position within the media at which playback should stop.
put_CurrentPosition Sets the position within the media at which playback should start.
put_PrerollTime Not currently implemented.
put_Rate Sets the playback rate, relative to normal playback of the media.
put_StopTime Sets the position within the media at which playback should stop.

 Last updated on Tuesday, July 13, 2004

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