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CSourceSeeking::ChangeStart

 
Microsoft DirectShow 9.0

CSourceSeeking::ChangeStart

The ChangeStart method is called when the start position changes.

Syntax

  virtual HRESULT ChangeStart(void) PURE;

Return Value

Returns an HRESULT value.

Remarks

The CSourceSeeking::SetPositions method calls this method if the start position changes. This method is pure virtual; the derived class must implement it. After a seek operation, time stamps should restart from zero. Media times should reflect the new start time. The following example shows a possible implementation:

HRESULT CMyStream::ChangeStart( )
{
    m_rtSampleTime = 0;          // Reset the time stamps.
    m_rtMediaTime = m_rtStart;   // Reset the media times.
    UpdateFromSeek();
    return S_OK;
}

Requirements

**  Header:** Declared in Ctlutil.h; include Streams.h.

**  Library:** Use Strmbase.lib (retail builds) or Strmbasd.lib (debug builds).

See Also