DirectShow 设置回调函数返回失败
如下设置回调函数 hr = m_pF->QueryInterface(IID_IVRControl, (void **)(&m_pVRControl)); 返回m_pVRControl为空;
是否IID_IVRControl错误? 有人遇到过吗?
// 接口的 GUID
static const GUID IID_IVRControl = {0x244df760, 0x7e93, 0x4cf0, {0x92, 0xf4, 0xdc, 0xb7, 0x9f, 0x64, 0x6b, 0x7e}};
IID_IVRControl
BOOL CDXGraph::CreateGrabber()
{
if(mGraph == NULL)
return FALSE;
HRESULT hr;
hr = CoCreateInstance(CLSID_lwVideoRenderer, NULL, CLSCTX_INPROC_SERVER,
IID_IBaseFilter, (void **)(&m_pF));
if(NULL == m_pF)
{
return false;
}
hr = mGraph->AddFilter(m_pF, L"VideoRenderer");
hr = m_pF->QueryInterface(IID_IVRControl, (void **)(&m_pVRControl));
return TRUE;
}