IAMStreamConfig::SetFormat method (strmif.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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 SetFormat method sets the output format on the pin.


HRESULT SetFormat(
  [in] AM_MEDIA_TYPE *pmt


[in] pmt

Pointer to an AM_MEDIA_TYPE structure that specifies the new format.

Return value

Returns an HRESULT value. Possible values include the following.

Return code Description
Insufficient memory.
NULL pointer value.
This media type is not valid.
The input pin is not connected.
Cannot set the type; the filter is not stopped.
Cannot set the type; the filter is not stopped.


This method specifies the format for the output pin. If the pin is not connected, it will use this format for its next connection. If the pin is already connected, it will attempt to reconnect with this format. The method might fail if the other pin rejects the new type.

If this method succeeds, subsequent calls to the IPin::EnumMediaTypes method will return the new type, and no others.

On most filters, this method fails if the filter is paused or running. On some compression filters, the method fails if the filter's input pin is not connected.

With some filters, you can call this method with the value NULL to reset the pin to its default format.

Filter Developers: The following remarks describe how to implement this method:

If the output pin is not connected, and the pin supports the specified media type, return S_OK. Store the media type and offer it as format number zero in the CBasePin::GetMediaType method. Do not offer other formats, and reject other formats in the CBasePin::CheckMediaType method.

If the pin is already connected, and the pin supports the media type, reconnect the pin with that type. If the other pin rejects the new type, return VFW_E_INVALIDMEDIATYPE and restore the original connection.


Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header strmif.h (include Dshow.h)
Library Strmiids.lib

See also

Error and Success Codes

IAMStreamConfig Interface