How to realize aggregation of multiple IP cameras?

Question

Video

We need a software (*nix, windows) solution that will help implement the following idea:
There are several IP cameras that broadcast rtsp streams. It is necessary to combine these streams into one, which will subsequently be given, for example, to YouTube, with a change of cameras (automatic, timed or random).
Leave options, paid or free - it doesn't matter. Xsplit has this functionality, but the switching of cameras there takes place with a delay of a couple of seconds, and at the same time switching a dark screen, which, as it were, does not suit at all.

Answer 1

Look towards ZoneMinder and ffmpeg . Here is a small example.