Using NDI Standard

Network Device Interface (NDI) is a standard used to receive, deliver, and control live video streams over an IP network, typically within a live production workflow. NDI uses a low-latency and high-quality compression codec, a typical HD stream (1080i) requiring about 100Mbps of data throughput.

Important

• StreamHub can support Full NDI, either for inputs or outputs.
• StreamHub does not support NDI HX nor HXv2.

NDI Inputs

StreamHub can receive the following protocols:

• Unicast UDP and TCP
• Multipath TCP
• Multicast UDP

No configuration is required. These protocols are automatically detected.

StreamHub can use simultaneously up to three discovery methods to combine and use multiple NDI sources on the network. The three discovery methods available are:

• mDNS (Multicast DNS)
  NDI Senders 'advertise' themselves on the network by emitting a multicast message which provides information about their IP address and port along with some other information. This is the discovery method used by default, no specific configuration is required on the StreamHub.
• Active Polling through Extra IP list
  • A list of IP addresses can be defined in the NDI input configuration, each IP address should correspond to a NDI source device
  • StreamHub will issue an active query message over TCP to each configured NDI source device and ask for a list of NDI Sources which are on offer
• Discovery Server (NDI Messaging server)
  • You can activate an NDI Messaging server in Settings > Network > NDI.
  • The NDI Discovery Server works by every NDI Source and every NDI receiver making a persistent socket connection to the server using TCP port 5959, and either announcing itself (sender), or constantly being informed of any changes in source availability (receiver).

NDI Outputs

• By default, only unicast transmission is activated.
• You can activate multicast transmission in Settings > Network > NDI.
• Enabling multicast mode activates multicast transmission for all NDI outputs of the StreamHub server. It is not possible to mix unicast and multicast outputs on a same server.

StreamHub supports mDNS to allow NDI receivers to detect NDI streams coming from the StreamHub.

Optionally, an NDI Discovery server (NDI messaging server) can also be used, for example in the case mDNS is not possible on the network.

If an NDI Discovery server is set, mDNS is not used by the NDI Outputs. This means that receivers must be connected directly to the StreamHub or to the same NDI Discovery server to see this source.

Note

• To receive NDI video streams from third-party devices, you must configure NDI input profiles and define transmission settings (please see the Configuring IP Input Profiles).
• In the Outputs section, the number of NDI outputs available depends on your StreamHub license. You can configure them by clicking on the

  

  icon in the output thumbnail, then on the

  

  icon. To get some help for configuration, click on the

  

  icon.

Audio level correction

When connecting an NDI device to the StreamHub, either on input or output, you can adjust the audio level to conform to the audio standard implemented by this device.

For both NDI input and output profiles, you can select among 3 possible values for the “Audio Standard”:

• None (default setting)
• EBU
• SMPTE 

The table below presents the effect in terms of dB offset for each input/output possible pairs.