CoInitialize/CoUninitialize will be unbalanced if app under single threaded COM

[ot32em]

At the videoInput::comInit, https://github.com/ofTheo/videoInput/blob/master/videoInputSrcAndDemos/libs/videoInput/videoInput.cpp#L1451

comUnInit() does not check whether the previous CoInitializeEx call in comInit() is failed or succeeded to call CoUninitialize. If the CoInitializeEx is failed because thread mode change, its internal reference count will not be added. Then still calling the CoUninitialize would cause the the CoInitialize/CoUninitialize unbalanced. Currently, it only send the warning as react.

See the remark of CoInitializeEx.

To close the COM library gracefully on a thread, each successful call to CoInitialize or CoInitializeEx, including any call that returns S_FALSE, must be balanced by a corresponding call to CoUninitialize.

In my project (under single threaded com), I met a bug that my internal COM dll is always unloaded too early only on Windows 7 x86 (still don't know why it only happen on win7). I used the IInitializeSpy to monitor the changes of reference count of CoInitialize. I notices the reference count is always dropped by 1 if one of my module using opencv library was loaded by LoadLibrary. Issue is gone after I unlink the highgui.dll from my project.