IVMRMixerControl9::GetAlpha

Microsoft DirectShow 9.0

IVMRMixerControl9::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. This value corresponds to the input pin. For example, the first input pin is stream 0.

pAlpha

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

Return Values

The method returns an HRESULT. Possible values include those in the following table.

Value	Description
S_OK	The method succeeded.
E_POINTER	pAlpha is invalid.
VFW_E_NOT_CONNECTED	The pin is not connected.

Requirements

Header: Include D3d9.h, Vmr9.h.

Library: Use Strmiids.lib.

See Also

• IVMRMixerControl9 Interface