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IAMVideoAccelerator::BeginFrame

 
Microsoft DirectShow 9.0

IAMVideoAccelerator::BeginFrame

The BeginFrame method begins frame processing.

Syntax

  HRESULT BeginFrame(
  const AMVABeginFrameInfo *pamvaBeginFrameInfo
);

Parameters

pamvaBeginFrameInfo

[in] Pointer to an AMVABeginFrameInfo structure containing the information needed to begin processing the frame.

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.

Return code Description
E_FAIL Failure.
E_INVALIDARG Argument is invalid.
E_NOTIMPL Method is not supported.
E_POINTER Null pointer argument.
S_OK Success.

Remarks

This method can only be called after the pins are connected.

The AMVABeginFrameInfo structure contains an index to the destination buffer. Valid index values are from zero to dwActualUncompSurfacesAllocated–1), obtained by calling IAMVideoAcceleratorNotify::SetUncompSurfacesInfo.

The decoder should not make any assumption about the initial contents of the frame, as the frame memory used might not be the same as the memory last used with this frame index.

A call to this method might block operation processing if no non-busy frame buffer is available.

Requirements

Header: Include videoacc.h.

Library: Use Strmiids.lib.

See Also