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IVMRMixerControl::GetAlpha

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Microsoft DirectShow 9.0

IVMRMixerControl::GetAlpha

The GetAlpha method retrieves the constant alpha value that is applied to this video stream.

Syntax

  HRESULT GetAlpha(

  
  DWORD
  
  dwStreamID
  
    float*
  
  pAlpha

  );

Parameters

dwStreamID

[in] Specifies the input stream.

pAlpha

[out]  Pointer to a variable of type float that receives the current alpha value.

Return Values

If the method succeeds, it returns S_OK. If it fails, it returns an error code.

Error Code Description
E_POINTER pAlpha is invalid.
VFW_E_NOT_CONNECTED The pin is not connected.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also