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IAMVideoAccelerator::QueryRenderStatus method (videoacc.h)

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The QueryRenderStatus method queries the read/write status of a DirectX Video Acceleration (DXVA) decoding surface.

Syntax

HRESULT QueryRenderStatus(
  [in] DWORD dwTypeIndex,
  [in] DWORD dwBufferIndex,
  [in] DWORD dwFlags
);

Parameters

[in] dwTypeIndex

Specifies the type of surface to query:

  • For a compressed surface, specify one of the DXVA surface types defined in dxva.h.
  • For an uncompressed output surface, set this parameter to 0xFFFFFFFF.

[in] dwBufferIndex

The zero-based index of the surface, within the pool of surfaces that were allocated for the specified surface type.

[in] dwFlags

Specifies the type of query to perform.

Value Meaning
Zero
Test whether the surface is safe to use for writing.
AMVA_QUERYRENDERSTATUSF_READ
Test whether the surface is safe to use for reading.

Return value

Returns an HRESULT value. Possible values include the following:

Return code Description
E_PENDING
The operation is still in progress.
S_OK
The operation is complete.
VFW_E_INVALIDSUBTYPE
The decoder did not use a DXVA decoding type when it connected to the video renderer.
VFW_E_NOT_CONNECTED
The pins on the decoder and video renderer filters are not connected.

Remarks

If the filter's pins are not connected, the method returns VFW_E_NOT_CONNECTED.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header videoacc.h
Library Strmiids.lib

See also

Error and Success Codes

How Decoders Use IAMVideoAccelerator

IAMVideoAccelerator Interface