Hello,
As much as I could understand from your description, you're using the C++ code as a COM object, which automatically reads its settings from registry (URL, username, password and video size) and starts streaming. So you want to have 6 instances, all with different settings written in the registry, so you could initiate Instance 1 with URL 1, Instance 2 with URL 2, etc.. Is this correct?
Where do you actually use the streaming object? On a web page? Who starts the streaming?
Anyway, I'm DirectShow proficient (as you can see from my past projects here) and I will have no problem in changing/adding those registry settings. I imagine that you have a custom DirectShow source filter built, that is using libcurl, so I would have to check the code to see if it is maybe using some static variables, in which case multiple instances from the same process would be difficult. But I will have to check first.
Thanks,
Goran.