DMOEnum
The DMOEnum function enumerates DMOs listed in the registry. The caller can search by category, media type, or both.
Syntax
HRESULT DMOEnum(
REFGUID guidCategory,
DWORD dwFlags,
DWORD cInTypes,
const DMO_PARTIAL_MEDIATYPE *pInTypes,
DWORD cOutTypes,
const DMO_PARTIAL_MEDIATYPE *pOutTypes,
IEnumDMO **ppEnum
);
Parameters
guidCategory
GUID that specifies which category of DMO to search. Use GUID_NULL to search every category. See DMO GUIDs for a list of category GUIDs.
dwFlags
Bitwise combination of zero or more flags from the DMO_ENUM_FLAGS enumeration.
cInTypes
Number of input media types to use in the search criteria. Use zero to match any input type.
pInTypes
Pointer to an array of DMO_PARTIAL_MEDIATYPE structures that contain the input media types. Specify the size of the array in the cInTypes parameter.
cOutTypes
Number of output media types to use in the search criteria. Use zero to match any output type.
pOutTypes
Pointer to an array of DMO_PARTIAL_MEDIATYPE structures that contain the output media types. Specify the size of the array in the cOutTypes parameter.
ppEnum
Address of a variable to receive the IEnumDMO interface of the enumerator.
Return Value
Returns an HRESULT value. Possible values include the following.
| Result Code | Description |
| E_FAIL | Failure |
| E_OUTOFMEMORY | Insufficient memory |
| S_OK | Success |
Remarks
This method returns a pointer to an enumerator object that supports the IEnumDMO interface. The application uses the IEnumDMO interface to enumerate over the set of DMOs that match the search criteria.
Requirements
Header: Declared in Dmoreg.h; include Dmo.h
Library: Msdmo.lib.
Example Code
The following example enumerates all audio effect DMOs on the user's system, including keyed DMOs.
IEnumDMO* pEnum = NULL;
HRESULT hr = DMOEnum(
DMOCATEGORY_AUDIO_EFFECT, // Category
DMO_ENUMF_INCLUDE_KEYED, // Included keyed DMOs
0, NULL, // Input types (don't care)
0, NULL, // Output types (don't care)
&pEnum);
if (SUCCEEDED(hr))
{
CLSID clsidDMO;
WCHAR* wszName;
do
{
hr = pEnum->Next(1, &clsidDMO, &wszName, NULL);
if (hr == S_OK)
{
// Now wszName holds the friendly name of the DMO,
// and clsidDMO holds the CLSID.
// Remember to release wszName!
CoTaskMemFree(wszName);
}
} while (hr == S_OK);
pEnum->Release();
}
See Also