DirectShow Animated Header -- IVPBaseNotify Interface DirectShow Animated Header -- IVPBaseNotify Interface* Microsoft DirectShow SDK
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IVPBaseNotify Interface


IVPBaseNotify enables you to control the properties of a filter that uses a video port. The IVPNotify interface derives from this interface. See also IVPBaseConfig and IVPConfig.

When to Implement

The Overlay Mixer filter implements this interface so you won't need to implement it in most cases. Implement this interface when you need to alter the default behavior.

When to Use

Use this interface in your application when you need to access video port properties.

Methods in Vtable Order
IUnknown methods Description
QueryInterface Retrieves pointers to supported interfaces.
AddRef Increments the reference count.
Release Decrements the reference count.
IVPBaseNotify methods Description
RenegotiateVPParameters Initializes the connection to the decoder.


IVPBaseNotify::RenegotiateVPParameters

IVPBaseNotify Interface

Initializes the connection to the decoder.

HRESULT RenegotiateVPParameters(void) PURE;

Return Values

Returns an HRESULT value that depends on the implementation of the interface. HRESULT can include one of the following standard constants, or other values not listed.
Value Meaning
E_FAIL Failure.
E_POINTER NULL pointer argument.
E_INVALIDARG Invalid argument.
E_NOTIMPL Method is not supported.
NOERROR No error.

Remarks

The Overlay Mixer filter negotiates various parameters (by using the IVPBaseConfig interface) with the decoder or driver. Call this function if any of those parameters (such as the video format or size) change. Currently, the Overlay Mixer repeats the whole connection process. You can call this method even while the graph is playing.

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