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Viz Engine Administrator Guide

Version 5.2 | Published March 20, 2024 ©

Shared Usage of Input Channels

This feature allows two or more instances of Viz Engine on one system to show the same content by using the same physical input without the need for a distribution amplifier.

Configuration

To share the input, all instances must have their corresponding input channels configured the same to be used.

Example: live_type1 = SDI1

The Viz Engine instance hosting the physical input needs the following value set in the config file:

Matrox.InputHost = 1

Important: Using shared inputs and setting this configuration value increases the overall in-to-out delay by 1 frame.

Important

The first instance of Viz Engine that is started owns the physical connector of the input. All other instances started after share the content on the video board. If the first instance (in control of the input connector) is closed, all other instances referring to that connector lose their content as well, and need to be closed and restarted again. There is no automatic recovery when the owning instance of Viz Engine crashes.

Note: It is imperative that the first engine fully boots before the others can allocate the shared resource.

Watchdog configuration is also not supported in this case.

Info: This feature is available on system topology SDI boards only (x.mio3, DSX.LE4 and successors).

Info: This feature also works if the requested connector is physically allocated by a Channel Recorder instance.

Sharing Inputs on X.mio5 ST 2110 Boards

This feature works differently on ST 2110 boards. It is possible to subscribe to the same multicast address on multiple connectors. Network switches won't send the same IP packet twice, so no bandwidth is lost. In an NMOS environment, this is straight forward by connecting the same sender to different receivers. For static (and potentially some SDN) setups, it is necessary to configure the same multicast address on the inputs in ipconfig.xml.

The important benefit of this approach compared to the dual channel SDI setup is that the inputs work individually, and the shutdown or stopping of one Viz Engine instance doesn't influence the other.