2.8 NDI, SRT and UDP Streaming Out (v.5.0 & v5.5)
With version 5.0, NDI® based Playout was introduced, and with version 5.5 we added support for SRT, UDP and ST-2110 Playout using qualified Apple hardware. Please note the following points when configuring a machine for streaming playout:
NDI will work just fine on INTEL-based Macs (Macmini8,1). For SRT and UDP Playout, an Apple silicon-based Mac mini (M1/M2), Mac Studio (Max or Ultra) or Mac Pro 2023 (Mac14,8) is highly recommended.
The faster the Mac, the more functions and a higher video codec quality can be achieved at the same time.
Although it is possible to run Just Out and Just Control on the same machine, we highly recommend running Just Control on a separate machine.
Realtime graphics are supported, but especially complex templates must be tested thoroughly before using them on air.
Notes
Setting up a Channel for streaming out is as easy as setting up a Channel using an AJA/Blackmagic Design SDI out, using the Wizard or the Channel setup inside the Just Control Configuration window.
The delay, between the time the signal is generated by the Just Out engine and received by the receiver, depends mainly on the buffer settings defined for the engine and the “application” that receives/requests the stream.
When the “Switch to Live” function is activated, but no live stream is received, the Just Out engine to reconnect to the defined stream every few seconds. The interval will depend on the used streaming format (NDI®, SRT or UDP) - and when using SRT, if the Just Out engine is the Caller (~0,5 sec.) or the Listener (~3 sec).
Using NDI, the “Live Input” stream can be changed in the “Settings” tab of the Multi Viewer while the channel is ON AIR. Using SRT or UDP, the Input stream has to be defined in the Streaming settings (“Just Control Configuration → Layers & Engines → Video → Configure Engines → Streaming”) and therefore cannot be changed while the channel is running.
Using NDI, we insert metadata like we would do it using SDI. This is because there is no standard available which describes the method which has to be used.
SRT and UDP streams support the SMPTE 2038 specifications related to the transport of VANC data (e.g. CEA-708, OP-47, SCTE-104) for both the output and the live input.
SRT and UDP streams support ATSC A/53 closed captions in the MPEG transport stream for both the output and the live input. When using a live input, the ATSC A/53 closed captions are disabled if the stream contains SMPTE 2038 information.
SRT and UDP streams support SCTE-35 events in the MPEG transport stream for both the output and the live input. When using a live input, SCTE-35 is disabled if the stream contains SMPTE 2038 information. Any SCTE-104 events scheduled using the “Event” option will be automatically converted to SCTE-35.
Adjustable encoding parameters. When configuring the engine, there is now a new “Streaming tab”, which allows to define the IP Address/Port for the outgoing and for the incoming “Live” stream. Additionally, the H.264 profile/bitrate as well as the AAC audio bitrate can be defined here for the outgoing SRT or UDP stream.
Supported “live” audio formats. Incoming SRT and UDP streams with MP2 (MPEG-1 Layer II) audio tracks in the MPEG transport stream are supported in addition to AAC encoded audio.
Limitations
The output stream is always progressive, but we do not deinterlace field-based movies at the moment. So please use movies which are progressive for the highest quality possible.
The incoming “Live signal” MUST match the Output Format defined for the Playout channel.
Only the “Buffered In” method to switch to live and 8bit modes are available using one of the available streaming methods.
Using SRT, we support Caller and Listener mode, but not Rendezvous at the moment.
Using UDP, only Unicast connections are supported at the moment.
It is possible that there are no “Skipped Frames” shown in the Just Out Diagnostic window, even there are skipped frames in the final stream.