IWMMediaProps::GetMediaType method (wmsdkidl.h)

[アーティクル]
4/26/2023

[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 It has been superseded by Source Reader and Sink Writer.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.]

The GetMediaType method retrieves a structure describing the media type.

Syntax

HRESULT GetMediaType(
  [out]     WM_MEDIA_TYPE *pType,
  [in, out] DWORD         *pcbType
);

Parameters

[out] pType

Pointer to a WM_MEDIA_TYPE structure. If this parameter is set to NULL, this method returns the size of the buffer required in the pcbType parameter.

[in, out] pcbType

On input, the size of the pType buffer. On output, if pType is set to NULL, the value this points to is set to the size of the buffer needed to hold the media type structure.

Return value

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

Return code	Description
S_OK	The method succeeded.
E_INVALIDARG	The pcbType parameter is NULL.
ASF_E_BUFFERTOOSMALL	The pcbType parameter is not large enough.

Remarks

You must make two calls to GetMediaType. On the first call, pass NULL as pType. On return, the value of pcbType will be set to the buffer size required to hold the WM_MEDIA_TYPE structure. Then you can allocate a buffer of the required size and pass a pointer to it as pType on the second call.

Requirements


Minimum supported client	Windows 2000 Professional [desktop apps only],Windows Media Format 7 SDK, or later versions of the SDK
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	wmsdkidl.h (include Wmsdk.h)
Library	Wmvcore.lib; WMStubDRM.lib (if you use DRM)