How to trigger repeating keep-alive SCTE messages

Available in OnTheAir Video versions 4.5.7 and later. 

For some workflows, encoders downstream of OnTheAir Video may expect SCTE-35 messages to arrive regularly. OnTheAir Video now has a simple solution to this in the Actions Editor pane (Toolbar> Window> Actions editor…). 

Send SCTE Splice Null Request 

As the name suggests, this new action sends a null splice request. This is a useful message when needing to receive the splice command structure and timing reference, but not necessarily a splice event to execute. Once you have configured the null action's AS Index and DPI PID, you may click "Save As…". A new dialog window will ask you to name this user action. Let's call this one "Null KeepAlive", then click save. You should see "Null KeepAlive" as a user action. Now that we have the user action made from above, we can begin a repeated command.  

Repeated Commands

First, let's discuss why a repeated null might be useful. Sending a Splice Null regularly is commonly used as a keep alive or heartbeat for processing chains. This tells equipment that the SCTE signal is still flowing, that there is no drift in the splice_time, and validation for broadcasters who want to confirm the SCTE path integrity outside of ad breaks. 

Click on your newly made user action and you will see there is a new checkbox in the dialog. Here you may set the repeat time in seconds with the lowest being 1 second intervals. Enabling the repeat will immediately begin the function. Make sure to click save when making any timing changes.