A video wall is actually a two or more TV displays, assembled together to form either a complete single large screen or a splitted large screen, or a group of screens which each one shows more than one input. Sometimes, a bunch of TVs showing the same content at the same time (like what you see in electrical depots) is also considered as a video wall.

When using NoviSign digital signage software on your Windows, Android or Chrome OS devices, you can form a video wall in one of 3 ways which I will specify in this technical post:

1) Using a video wall switcher

The switcher is also known as “matrix switcher” or “switch” or “splitter” or “controller” or “video wall processor”. This is the most simple video wall implementation. The video wall switcher is a device (bigger than a TV box) that can take input from one or more video feeds (usually by HDMI port). The switcher will then split the video signal into multiple outputs (each one goes to a simple TV display). Depending on the video wall switcher, you can set your output to different formats: Example: 2 x 2, 3 x 3, 4 x 4, 4 x 1, or else. Some video wall switchers can show you 2 or 4 video inputs on each of your TV displays. A good switcher we tried was of Kramer Electronics, which has branches at 35 countries in the world. Also, another interesting solution is by a company called Userful, which has unique video wall combinations. Of course, you can use other video wall hardware solutions, together with your NoviSign based mini PC / TV box / dongle. Usually, a switcher is an expensive hardware, but does the job very well.
Video wall switcher

2) Using professional TV displays

For this option (which is also known as “Daisy chain” or “chaining displays”), you need to purchase industrial and/or professional TV displays, which cost 2 or 3 times more than a simple TV display. Professional digital signage displays have built-in features to allow you creating video walls. This is done by connecting one screen to another through HDMI, DVI or DisplayPort. This process is called daisy chaining, since the displays are like one chain: the 1st one is connected to the 2nd one, the 2nd one is connected to the 3rd one, the 3rd one is connected to the 4th one and so on. You can have 2 or more TVs like that in this constellation. Your NoviSign based mini PC / TV box / dongle will be connected to the 1st display. Each display TV should be configured according to its position on the video wall. Here is a tutorial video of how to create a videowall using LG professional TV display.
Chaining professional TV displays

3) Using NoviSign sync feature

This option is unique to NoviSign. The synchronization feature allows you to synchronize the clock of multiple separate units (which can be an assortment of Android, Windows or ChromeOS players). Each unit is connected to a simple TV display. One of the synched units will act as an NTP server that sends time pluses every minute to all the other units. The main advantage of this option is that you can put a different playlist in each synched unit, in order to display something which is made of different content (like a sentence, in which each word appears on a different screen). Another important advantage of this option is the resolution: while in the 2 above options, you are limited to the maximum screen resolution supported by the TV box which is connected to the video wall (which is probably not more than 4K, which is 3840 x 2160; on a 2 x 2 video wall each TV will have a resolution of a portion of the original content, i.e. 1920 x 1080 and on a 4 x 4 video wall each TV will have a resolution of 960 x 540 pixels, which might look pixelated or blur on big TVs). In this option you are not limited like that: each TV box is independent, that means you can have a video of 7680 x 1080 pixel (which cannot be played by any TV box, due to its high resolution), then cut it (using a cropping software tool like Movavi) into 4 different 1920 x 1080 videos (which any TV box which supports full HD resolution can display), which will be used in 4 different creatives / playlists to be displayed synchronized, each one one on each of the 4 different TV boxes.
There are 2 disadvantages to this options: a. if the network stops working or no communication to the NTP server, the units may get out of synchronization after awhile; b. you can use only single slide playlist, which has a slideshow widget with multiple slides (videos, images, text) within. Playlist with more than one slide won’t work.
To use this option, please refer to this user guide.
Synchronized separate units

Other interesting options

Other options can be using a Chromebox that plays NoviSign app and shows the same content on 2 different displays (by connecting the 1st display TV to the HDMI port of the Chromebox and connecting the 2nd display TV to the DisplayPort of the Chromebox). This can be done also in Windows miniPC with more than one HDMI port. You can also use an extended display (only when using a Windows TV box of 8GB RAM, strong processor and more than one HDMI port) to run the NoviSign app in more than once instance on the same player, when each app instance is broadcasted to a different display (see this post, under the title “How to run the native Windows app in extended displays?”). Please notice that using videos in this case will look good on not more than 2 displays.

Nir.