MFGetTopoNodeCurrentType function (mfidl.h)

Gets the media type for a stream associated with a topology node.

Syntax

HRESULT MFGetTopoNodeCurrentType(
        IMFTopologyNode *pNode,
        DWORD           dwStreamIndex,
        BOOL            fOutput,
  [out] IMFMediaType    **ppType
);

Parameters

pNode

A pointer to the IMFTopologyNode interface.

dwStreamIndex

The identifier of the stream to query. This parameter is interpreted as follows:

• Transform nodes: The value is the zero-based index of the input or output stream.
• All other node types: The value must be zero.

fOutput

If TRUE, the function gets an output type. If FALSE, the function gets an input type. This parameter is interpreted as follows:

• Output nodes: The value must be TRUE.
• Source nodes: The value must be FALSE.
• Tee nodes: The value is ignored.
• Transform nodes: If the value is TRUE, the dwStreamIndex parameter is the index for an output stream. Otherwise, dwStreamIndex is the index for an input stream.

[out] ppType

Receives a pointer to the IMFMediaType interface. The caller must release the interface.

Return value

The function returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Remarks

This function gets the actual media type from the object that is associated with the topology node. The pNode parameter should specify a node that belongs to a fully resolved topology. If the node belongs to a partial topology, the function will probably fail.

Tee nodes do not have an associated object to query. For tee nodes, the function gets the node's input type, if available. Otherwise, if no input type is available, the function gets the media type of the node's primary output stream. The primary output stream is identified by the MF_TOPONODE_PRIMARYOUTPUT attribute.

Requirements

See also

Media Foundation Functions