The following set the callback function hr=m_pF - & gt; QueryInterface (IID_IVRControl, (void * *) (& amp; M_pVRControl)); Return m_pVRControl is empty;

Whether IID_IVRControl mistake? Someone met?

//interface GUID
X244df760 static const GUID IID_IVRControl={0, 0 x7e93, 0 x4cf0, {xf4 0 x92, 0, 0 XDC, 0 xb7, 0 x9f, x64, 0 0 x6b, 0 x7e}};

IID_IVRControl

BOOL CDXGraph: : CreateGrabber ()
{
If (mGraph==NULL)
Return FALSE;

Retrieves the hr;

Hr=CoCreateInstance (CLSID_lwVideoRenderer, NULL, CLSCTX_INPROC_SERVER,
IID_IBaseFilter, (void * *) (& amp; M_pF));

If (NULL==m_pF)
{

return false;
}

Hr=mGraph - & gt; AddFilter (m_pF, L "VideoRenderer");

Hr=m_pF - & gt; QueryInterface (IID_IVRControl, (void * *) (& amp; M_pVRControl));

Return TRUE;
}

CodePudding user response:

Refer to the http://www.360doc.com/content/13/1105/10/10724725_326751558.shtml