IMemInputPin::GetAllocator

 
Microsoft DirectShow 9.0

IMemInputPin::GetAllocator

The GetAllocator method retrieves the memory allocator proposed by this pin. After the allocator has been selected, this method returns a pointer to the selected allocator.

Syntax

  HRESULT GetAllocator(
  IMemAllocator **ppAllocator
);

Parameters

ppAllocator

[out] Receives a pointer to the allocator's IMemAllocator interface. The caller must release the interface.

Return Values

Returns an HRESULT value. Possible values include those shown in the following table.

Return code Description
S_OK Success.
VFW_E_NO_ALLOCATOR No allocator is available.

Remarks

When an output pin connects to an input pin, it negotiates with the input pin to decide on a memory allocator. The output pin calls this method to retrieve the input pin's proposed allocator. It calls the IMemInputPin::NotifyAllocator method to specify which allocator it selected.

If this method succeeds, the IMemAllocator interface has an outstanding reference count. Be sure to release it when you are done.

Requirements

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

Library: Use Strmiids.lib.

See Also