CBaseInputPin::GetAllocator

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Windows Embedded CE 6.0 R3

4/8/2010

Retrieves the allocator interface that this input pin identifies as the interface for the output pin to use.

Syntax

HRESULT GetAllocator(
  IMemAllocator** ppAllocator
);

Parameters

• ppAllocator
  Pointer to an obtained IMemAllocator object.

Return Value

Default implementation returns either E_OUTOFMEMORY, if an allocator cannot be created, or NOERROR upon success.

Remarks

This member function implements the IMemInputPin::GetAllocator method, which is called by the connected output pin to retrieve an allocator to use for transporting media samples.

By default, this member function creates a CMemAllocator object and obtains the IMemAllocator interface, to which it adds a reference count for the pin when assigning it to the m_pAllocator data member, and adds another reference count before passing it back to the output pin.

Override this member function if your filter has another allocator, such as one from a downstream pin, or a specialized allocator to offer the connected output pin.

Requirements