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Video: NMOS IS-07, GPI Replacement and Much, Much More…

Posted on 15th January 2020 by Russell Trafford-Jones

GPI was not without its complexities, but the simplicity of its function in terms of putting a short or a voltage on a wire, is unmatched by any other system we use in broadcasting. So the question here is, how do we do ‘GPI’ with IP given all the complexity, and perceived delay, in networked communication. CTO of Pebble Beach, Miroslav Jeras, is here to explain.

The key to understanding the power of the new specification for GPI from NMOS called IS-07 is to realise that it’s not trying to emulate DC electronics. Rather, by adding the timing information available from the PTP clock, the GPI trigger can now become extremely accurate – down to the audio sample – meaning you can now use GPI to indicate much more detailed situations. On top of that, the GPI messages can contain a number of different data types, which expands the ability of these GPI messages and also helps interoperability between systems.

Miroslav explains the ways in which these messages are passed over the network and how IS-07 interacts with the other specifications such as IS-05 and BCP-002-01. He explains how IS-07 was used in the Techno Project – tpc, Zurich and then takes us through a range of different examples of how IS-07 can be used including synchronisation of the GUI and monitoring as well as routing based on GPI.

Watch now! | Download the slides

Speakers

Miroslav Jeras
CTO,
Pebble Beach Systems

Video: Wide Area Facilities Interconnect with SMPTE ST 2110

Posted on 17th December 2019 by Russell Trafford-Jones

Adoption of SMPTE’s 2110 suite of standards for transport of professional media is increasing with broadcasters increasingly choosing it for use within their broadcast facility. Andy Rayner takes the stage at SMPTE 2019 to discuss the work being undertaken to manage using ST 2110 between facilities. In order to do this, he looks at how to manage the data out of the facility, the potential use of JPEG-XS, timing and control.

Long established practices of using path protection and FEC are already catered for with ST 2022-7 for seamless path protection and ST 2022-5. New to 2110 is the ability to send the separate essences bundled together in a virtual trunk. This has the benefit of avoiding streams being split up during transport and hence potentially suffering different delays. It also helps with FEC efficiency and allows transport of other types of traffic.

Timing is key for ST 2110 which is why it natively uses Precision Timing Protocol, PTP which has been formalised for use in broadcast under ST 2059. Andy highlights the problem of reconciling timing at the far end but also the ‘missed opportunity’ that the timing will usually get regenerated therefore the time of media ingest is lost. This may change over the next year.

The creation of ST 2110-22 includes, for the first time, compressed media into ST 2110. Andy mentions that JPEG XS can be used – and is already being deployed. Control is the next topic with Andy focussing on the secure sharing of NMOS IS-04 & 05 between facilities covering registration, control and the security needed.

The talk ends with questions on FEC Latency, RIST and potential downsides of GRE trunking.

Watch now!
Speaker

Andy Rayner
Chief Technologist,
Nevion

Video: Broadcast 101 – Audio in an IP Infrastructure

Posted on 15th November 2019 by Russell Trafford-Jones

Uncompressed audio has been in the IP game a lot longer than uncompressed video. Because of its long history, it’s had chance to create a fair number of formats ahead of the current standard AES67. Since many people were trying to achieve the same thing, we find that some formats are compatible with AES67 – in part, whilst we that others are not compatible.

To navigate this difficult world of compatibility, Axon CTO Peter Schut continues the Broadcast 101 webinar series with this video recorded this month.

Peter starts by explaining the different audio formats available today including Dante, RAVENNA and others and outlines the ways in which they do and don’t interoperate. After spending a couple of minutes summarising each format individually, including the two SMPTE audio formats -30 and -31, he shows a helpful table comparing the,

Timing is next on the list discussing PTP and the way that SMPTE ST 2059 is used then packet time is covered explaining how the RTP payload fits into the equation. This payload directly affects the duration of audio you can fit into a packet. The duration is important in terms of keeping a low latency and is restricted to either 1ms or 125 microseconds by SMPTE ST 2110-30.

Peter finishes up this webinar talking about some further details about the interoperability problems between the formats.

Watch now!

Speaker

Peter Schut
CTO,
Axon

Video: IP Test and Measurement for ST 2110 Systems

Posted on 30th October 2019 by Adam K

As the transition to IP-based transport for video, audio, and data continues. The early adopters have already demonstrated the operational and commercial benefits of COTS IP infrastructure and SMPTE ST 2110 video-over-IP standard suite becomes mature now. However, configuration and troubleshooting of IP systems requires a completely new skillset. Broadcast engineers need to gain an understanding of the technology and the new techniques required to monitor these signals.

In this video Kevin Salvidge from Leader shows what test and measurement tools you need to ensure you continue to deliver the same quality of service that can be achieved with SDI systems.

Kevin looks at the main differences between traditional and IP systems which stem as much from a move from synchronous to asynchronous infrastructure as the way you measure how well the system is working.

The following topics are covered:

Frame Check Sequence (FCS), Cyclic Redundancy Check (CRC)
Packet jitter measurement (avoiding buffer underrun)
Monitoring ST 2022-7 path delay between the two feeds
PTP synchronization (offset and delay graphs, synchronisation accuracy)
Checking that video, audio and ANC signals are synchronised with PTP and RTP timing measurement
Packet Header Information looking at MAC, IP, UDP, RTP as well as the payload
SFP Information (10/25 Gb, multimode / single mode etc.)
IP Event Log e.g. Grand Master change
Hybrid IP and SDI Video and Audio Test and Measurement

You can see the slides here.

Watch now!

Speaker