Bagikan melalui

CBaseRenderer::Receive

  • Artikel
 
Microsoft DirectShow 9.0

CBaseRenderer::Receive

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

Syntax

  virtual HRESULT Receive(
    IMediaSample *pMediaSample
);

Parameters

pMediaSample

Pointer to the sample's IMediaSample interface.

Return Value

Returns S_OK if successful, or an HRESULT value indicating the cause of the error.

Remarks

The input pin calls this method when it receives a sample from the upstream filter.

If the filter is running, this method performs the following steps:

  1. Schedules the sample for rendering (CBaseRenderer::PrepareReceive).
  2. Waits for the scheduled time (CBaseRenderer::WaitForRenderTime).
  3. Renders the sample (CBaseRenderer::Render).
  4. Releases the sample (CBaseRenderer::ClearPendingSample).

If the filter is paused, the method performs the following steps:

  1. Notifies the derived class that a sample is available (CBaseRenderer::OnReceiveFirstSample).
  2. Waits for the scheduled time.
  3. Renders the sample.
  4. Releases the sample.

While paused, the method waits in step 2 until the filter switches to a running state. At that point, the filter schedules the sample.

In the base class, the OnReceiveFirstSample method does nothing. The derived class can override it. For example, when a video renderer is paused, it displays the first sample as a still image.

Requirements

**  Header:** Declared in Renbase.h; include Streams.h.

**  Library:** Use Strmbase.lib (retail builds) or Strmbasd.lib (debug builds).

See Also