IKsTopologyInfo::get_NumCategories method (vidcap.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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 get_NumCategories method returns the number of categories for this filter.
Syntax
HRESULT get_NumCategories(
[out] DWORD *pdwNumCategories
);
Parameters
[out] pdwNumCategories
Receives the number of categories.
Return value
The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.
| Return code | Description |
|---|---|
|
The method succeeded. |
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP with SP2 [desktop apps only] |
| Minimum supported server | Windows Server 2003 R2 [desktop apps only] |
| Target Platform | Windows |
| Header | vidcap.h |