While I’ve made programs that play in a vertical screen, I’ve never done it for multiple monitors in a video wall. I did it all in AfterFX. There are different control boxes for video walls that can affect which feeds to the system are displayed where. You need to find find what equipment they’re using. Then you can contact the manufacturer for all the details.
Maybe a search on the AfterFX forum for video wall will turn up some guidance. I seem to recall reading a thread about how someone approached this issue. I think they made a composition for each screen then added those comps into a master comp that displayed them as one. That way the synchronization could be checked. If you need to supply just one stream to the video wall, it would be that master comp’s movie. If you need 4 streams then just the individual comp’s movies.
Check out Alcorn McBride. They make a line of digital players used in many museums, themeparks, etc. If your client hasn’t chosen a playback system, maybe you can influence that decision. I’ve worked with Alcon’s tech support and they’re first rate. https://www.alcorn.com/
John
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