You are talking about digital signage and there are about 1,000 different companies making hardware and software for it. It is almost all remotely managed. Making content for the displays is the tough part of it all.
Google 'DIGITAL SIGNAGE' and you will get a ton of hits.
Visix, VBrick, Broadsign, Haivision, and Scala are just a few of the companies out there involved with digital signage.
Here is a website that has a list of the hundreds of companies involed with digital signage with links to their websites.http://www.digitalsignageexpo.net/exhibitor-list?items_per_page=20
- Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.