CBasePin.EnumMediaTypes method
[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 EnumMediaTypes method enumerates the pin's preferred media types. This method implements the IPin::EnumMediaTypes method.
Syntax
HRESULT EnumMediaTypes(
IEnumMediaTypes **ppEnum
);
Parameters
-
ppEnum
-
Address of a variable that receives a pointer to the IEnumMediaTypes interface.
Return value
Returns an HRESULT value. Possible values include those in the following table.
| Return code | Description |
|---|---|
|
Success. |
|
Insufficient memory. |
|
NULL pointer argument. |
Remarks
Input pins are not required to enumerate any preferred types. Output pins must enumerate at least one preferred type. Otherwise, both pins could lack a preferred type, making a connection impossible.
The IEnumMediaTypes interface works like a standard COM enumerator. For more information, see Enumerating Objects in a Filter Graph. If the method succeeds, the IEnumMediaTypes interface has an outstanding reference count. Be sure to release it when you are done.
The CEnumMediaTypes base class implements IEnumMediaTypes. It calls the pin's CBasePin::GetMediaType method to enumerate the media types.
Requirements
| Requirement | Value |
|---|---|
| Header |
|
| Library |
|