Synchronized content

This page is related to Multiscreen synchronization.

Introduction

In the digital signage context, synchronized content refers to the seamless coordination of multimedia elements across multiple displays. There are several ways to create synchronized content, depending on whether that content is meant to be displayed over a video wall and/or it is bound to the real time (as in "play this video synchronously on all screens from 9:15 to 9:30 on workdays and one hour later during weekend").

To ensure that the multimedia elements are perfectly timed and aligned across multiple displays, the players must be time-synchronized as well.

How to create synchronized content

Using an Elementi schedule

This method is employed when the content must be synchronized with the real time, as in "play this video synchronously on all screens from 9:15 to 9:30 on workdays and one hour later during weekend". Follow these steps:

Create an Elementi schedule in your project,
Add it to the main index.svg
Include the rest of the content through this schedule.

Using a multiscreen project

This method is employed when the content must be synchronized on multiple screens, usually grouped as a video wall, without an explicit bound to the real time, as above. It could also be used when the screens are not part of a video wall, however, since the multiscreen project contains the content for all the screens, it might get quite large, thus you need to make sure the storage space on each player is sufficient.

See how to create a multiscreen project.

Combining both methods

If the content must be synchronized on a video wall and also linked to the real time, then use a multiscreen project with an Elementi schedule inside it, driving the content.

Note:

The begin attribute should be removed from the main index.svg.

Advanced users

You can also use the begin attribute technique or even the Shared Variables mechanism to make synchronized content.

Content requirements

The most important requirement is to have content that either has an indefinite duration, or has a fixed duration (e.g. "0:01:00") and is set to repeat.

That means an "Automatic" (or "media") value as duration must be avoided.
The video layers usually have the duration set to their length, but it's always good to check if that's set or not.
Layers like text, images, backgrounds, clocks etc. don't need any changes (can be left with their default values).
Some widgets (or templates) might come by default with the duration set to "media" - make sure to change it to a fixed duration.

Additional requirements:

For Elementi:

The playlist can be set to loop only if all the media items within have fixed durations. If this condition is not respected, then the following warning message will be shown on the screen: Playlist is looping inside a schedule but does not meet the condition to be synchronised. See Playlist Troubleshooting page for more details.

For HMD:

start-at-random-time attribute

fixed duration & repeat

When including an SVG file, like playlist, news template, interactivity template, SVG animation etc., that has an indefinite duration into another SVG document, the new layer will get by default a "media" duration. This must be changed to a fixed duration (e.g. "0:01:00") and must be set to repeat indefinitely using the layer properties (as shown in the image on the right).
If you are using the news templates in your project, make sure that they are not displayed on more than one screen (see limitations section) and that the spx:start-at-random-time attribute is set to "Off".
The playlist should not loop - i.e. make sure that Enable Looping is set to "off" in the Properties tab.

If the above are not set correctly, the players might restart and end-up in safe mode!