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IMemInputPin::Receive method

Applies to: desktop apps only

The Receive method receives the next media sample in the stream.

Syntax

Copy

HRESULT Receive(
  [in]  IMediaSample *pSample
);

Parameters

pSample [in]: Pointer to the sample's IMediaSample interface.

Return value

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

Return code	Description
S_OK	Success.
S_FALSE	The sample was rejected.
E_POINTER	NULL pointer argument.
VFW_E_INVALIDMEDIATYPE	Invalid media type.
VFW_E_RUNTIME_ERROR	A run-time error occurred.
VFW_E_WRONG_STATE	The pin is stopped.

Remarks

This method is synchronous and possibly blocking. The pin does one of the following:

Rejects the sample.
Returns immediately and processes the sample in a worker thread.
Processes the sample before returning.

In the last case, the method might block indefinitely. If this might happen, the IMemInputPin::ReceiveCanBlock method returns S_OK.

If the pin uses a worker thread to process the sample, it holds a reference count on the sample. In any case, the output pin cannot directly re-use this sample. It must call the IMemAllocator::GetBuffer method to obtain a new sample.

If this method returns S_FALSE or an error code, the upstream filter should stop sending samples until the graph stops or completes a flush operation. Typical reasons for an S_FALSE return value include:

The downstream pin is flushing; that is, it received a BeginFlush call and has not yet received an EndFlush call.
The downstream filter detected the end of the stream. (See End-of-Stream Notifications.)

Requirements