Slates: An Overview

When building the final playlist for playout, the system needs some specific videos to be able to round out the schedule, called Slates. These are critical for a smooth playback and a good user experience under a variety of scenarios. 

An important thing to keep in mind about slates in linear channels: they cannot be scheduled in the traditional fashion; so when you go to plan out your schedule for the hour and day in the CMS, slates don't appear as pluggable content in your scheduler. Instead, they'll automatically supplement your scheduled content as needed. More details on the when's and why's of that process below.

If you'd rather not read through the different types of slates below, check out this handy video guide! 

Note: The playout engine requires videos to be a minimum of 15 seconds long. The ONLY exception is that bumpers before/after ad breaks are allowed to be as short as 3 seconds, but they can only be used in that context. 

General slate requirements:

Slates should have some branding for your channel to better help viewers know your linear channel and brand.

Slates should be of the same quality as your highest quality linear playback environment-- for example if you are scheduling a 1080p stream, then you should have 1080p slates. 

Please deliver separate slates with Audio and with the Audio Track Muted as certain platforms require no audio on slates. If you have no audio in your slate, please still include an audio track.

Ideally, your slates framerate should try to match the framerate of the content.  If most of your content is at 24fps then your slate should be at 24fps.  If your content has varying framerates, then try to get something that is mathematically close-- i.e. going from 23.97fps to 24fps is not ideal, but 23.97fps to 29.97fps is ok. 30fps to 24fps and back is fine, but 30fps to 23.97fps is not ideal.

Placeholder Slate

We request a 5 minute video. This should be branded, and have some minimal motion visible, so the end user can tell their device is still playing back. Think of this as a block of clay that we can use to fill in gaps in the schedule. Placeholder is only inserted by the system if there is a break in the schedule that cannot be filled by any Fallback lists you have assigned, and will be cut to fill the break.

If there are multiple placeholder slates associated with a given channel, the system will randomly select them to fill breaks.  Placeholder slates should NOT have countdown timers.

Ad Slate

If no specific ad slate(s) are uploaded, the system will use the first two minutes of the Placeholder Slate. 

Ad Slate runs during ad breaks. Any ads that fill will replace that portion of the ad break. 

For example, if I have a 2 minute ad break, and I get a :30 second and a :15 second ad, then I will see :45 seconds of ads, then the remaining 1:15 of ad slate, then back to my programming. 

As with placeholder slates, it is important to have an interruptible ad slate, because actual commercials will replace some or all of it, and you want to make sure that the user has a smooth experience-- it can be jarring to jump back into loud music, or some piece of larger movement that is already in-process.

It is helpful to have a countdown timer that counts back from from 2:00 to 00:00 to let the view know when the ad slate will end and programming with begin.

Some distribution partners have very specific requirements about ad slates, and we will advise you of any specific requirements if distributing to those platforms. 

If there are multiple ad slates associated with the linear channel, the playback engine will randomly select an ad slate per video. It is not a rotation of ad slates, so it is not guaranteed that they will alternate. The system will also use the same ad slate for every ad break within a given video-- it is only when a new video is loaded that the system will randomly select a new ad slate. 

Emergency Slate

The playback engine has a default "We'll be right back" slate in black and white, but you are free to provide a branded message. The emergency slate should be:

• 3-4 seconds long
• silent
• loopable (meaning it can be repeated smoothly)
• 1920x1080 at 5Mbps at a similar frame rate to the rest of your content
• should be distinct from any other slates in the system, so that your administrative users and/or the OTTera team can easily identify the slates' playback, without alerting your viewers to any problems. 

Emergency Slate plays out in the following scenarios:

1. Video file can't be reached for a scheduled segment and/or transcoding issues with the scheduled asset. If for some reason the playback engine has trouble reaching a video for some reason, or is unable to correctly load all of the scheduled video's resources, it will insert in the Emergency Slate to prevent the channel from going dark entirely. It will loop the emergency slate, and continue trying to retrieve the scheduled video.
2. Gap or misalignment in schedule. As above, if the system cannot fit another video in fallback, or the gap is sub 3s, the playback system will automatically insert the Emergency Slate. It sometimes happens that the a given video length is slightly over-reported, and it completes before the playback system "expects" it to. In order to stay consistent with the EPG, the playback engine will automatically insert Emergency Slate until the next video is scheduled to start.

To learn more about scheduling additional content to flush out your linear schedule, please see our article about adding Bumpers.