Collapse All Expand All

IltmfConvert::GetPreferredMediaSourceHandler

#include "ltmf.h"

C Syntax	HRESULT IltmfConvert_GetPreferredMediaSourceHandler(pConvert, MediaSourceHandlerType, pVal)
C++ Syntax	HRESULT GetPreferredMediaSourceHandler(MediaSourceHandlerType, pVal)

 

IltmfConvert *pConvert;	/* pointer to an interface */
long MediaSourceHandlerType	/* value of a media source handler type */
BSTR *pVal;	/* pointer to a string */

Retrieves the preferred media source handler's GUID set using IltmfConvert::SetPreferredMediaSourceHandler.

Parameter	Description
pConvert	Pointer to an IltmfConvert interface.
MediaSourceHandlerType	Value that indicates the media source handler type. For a list of possible values, refer to ltmfConvert_PreferredMediaSourceHandler Constants.
pVal	Pointer to a string to be updated with the media source handler's GUID. For a list of possible values, refer to ltmfMediaSourceHandler Constants.

Returns

S_OK	The function was successful.
<> S_OK	An error occurred. Refer to the Error Codes or the HRESULT error codes in the MediaFoundation documentation.

Comments

This method can be used to determine whether a preferred media source handler has been set by IltmfConvert::SetPreferredMediaSourceHandler. It will return NULL (if no preferred filter has been set) or a GUID indicating the preferred media source handler.

This GUID uniquely identifies the media source handler. Every media format has a registered media source handler(s) who are responsible of creating a media source for this media type.

For example, the GUID for the LEAD MPEG2 Transport Media Source Handler is:

EFE626C3-0A2C-49FA-8A01-3768B559B6DA

If the method succeeds, the caller must free the returned string by calling the SysFreeString function.

A list of display names for common LEAD filters can be found in ltmfMediaSourceHandler Constants.

Please see IltmfConvert::SetPreferredMediaSourceHandler for more information on media source handler GUID.

Required DLLs and Libraries

LTMF For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64

See Also

Elements:	IltmfConvert::SetPreferredMediaSourceHandler
Topics:	Media Foundation Function Groups
	ltmfMediaSourceHandler Constants
	ltmfConvert_PreferredMediaSourceHandler Constants

Example

For a C++ example, refer to .IltmfConvert::SetPreferredMediaSourceHandler Example for C++