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Removing Metadata Attributes

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[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

You can remove a metadata attribute by passing its index and stream number to the IWMHeaderInfo3::DeleteAttribute method. The order in which the remaining attributes are indexed after removing an attribute does not change; all remaining attributes that originally had an index value greater than the one removed have their index values reduced by one. When removing multiple attributes, do so in descending order by index to avoid having to calculate the adjustment in indexing.

For convenience in removing values, the IWMHeaderInfo3::GetAttributeIndices method returns the index values in descending order.

Note

Index values obtained by using the methods of IWMHeaderInfo3 are not compatible with index values obtained by using the methods of IWMHeaderInfo. If you use the methods of one interface to change attributes in a file, you should assume that any index values previously retrieved from the other interface are no longer valid and must be obtained again. You should avoid using the methods of IWMHeaderInfo if possible.

 

Working with Metadata