Video: Where can SMPTE 2110 and NDI co-exist?

When are two video formats better than one? Broadcasters have long sought ‘best of breed’ systems matching equipment as close as possible to your ideal workflow. In this talk we look getting the best of both compressed, low-latency and uncompressed video. NDI, a lightly compressed, ultra low latency codec, allows full productions in visually lossless video with a field of latency. SMPTE’s ST-2110 allows full productions with uncompressed video and almost zero latency.

Bringing together the EBU’s Willem Vermost who paints a picture from the perspective of public broadcasters who are planning their moves into the IP realm, Marc Risby from UK distributor and integrator Boxer brings a more general view of the market’s interest and Will Waters who spent many years in Newtek, the company that invented NDI we hear the two approaches of compressed and uncompressed compliment each other.

This panel took place just after the announcement that Newtek had been bought by VizRT, the graphics vendor, who sees a lot of benefit in being able to work in both types of workflow, for clients large and small and who have made Newtek its own entity under the VizRT umbrella to ensure continued focus.

A key differentiator of NDI is it’s focus on 1 gigabit networking. Its aim has always to enable ‘normal’ companies to be able to deploy IP video easily so they can rapidly benefit from the benefits that IP workflows bring over SDI or other baseband video technologies. A keystone in this strategy is to enable everything to happen on normal, 1Gbit switches which are prevalent in most companies today. Other key elements to the codec are: free, software development kit, bi-directionality, resolution independent, audio sample-rate agnostic, tally support, auto discovery and more.

In the talk, we discuss the pros and cons of this approach where interoperability is assured as everyone has to use the same receive and transmit code, against having an standard such as SMPTE ST-2110. SMPTE ST-2110 has the benefit of being uncompressed, assuring the broadcaster that they have captured the best possible quality of video, promises better management at scale, tighter integration into complex workflows, lower latency and the ability to treat the many different essences separately. Whilst we discuss many of the benefits of SMPTE ST-2110, you can get a more detailed overview from this presentation from the IP Showcase.

Watch now!

This panel was produced by IET Media, a technical network within the IET which runs events, talks and webinars for networking and education within the broadcast industry. More information

Speakers

Willem Vermost Willem Vermost
Senior IP Media Technology Architect,
EBU
Marc Risby Marc Risby
CTO,
Boxer Group
Will Walters Will Waters
Vice President Of Worldwide Customer Success,
VizRT
Russell Trafford-Jones Moderator: Russell Trafford-Jones
Exec Member, IET Media
Manager, Support & Services, Techex
Editor, The Broadcast Knowledge

Video: 2019 What did I miss? – Introducing Reliable Internet Streaming Transport

By far the most visited video of 2019 was the Merrick Ackermans’ review of RIST first release. RIST, the Reliable Internet Stream Transport protocol, aims to be an interoperable protocol allowing even lossy networks to be used for mission-critical broadcast contribution. Using RIST can change a bade internet link into a reliable circuit for live programme material, so it’s quite a game changer in terms of cost for links.

An increasing amount of broadcast video is travelling over the public internet which is currently enabled by SRT, Zixi and other protocols. Here, Merrick Ackermans explains the new RIST specification which aims to allow interoperable internet-based video contribution. RIST, which stands for Reliable Internet Stream Transport, ensures reliable transmission of video and other data over lossy networks. This enables broadcast-grade contribution at a much lower cost as well as a number of other benefits.

Many of the protocols which do similar are based on ARQ (Automatic Repeat-reQuest) which, as you can read on wikipedia, allows for recovery of lost data. This is the core functionality needed to bring unreliable or lossy connections into the realm of usable for broadcast contribution. Indeed, RIST is an interesting merging of technologies from around the industry. Many people use Zixi, SRT, and VideoFlow all of which can allow safe contribution of media. Safe meaning it gets to the other end intact and un-corrupted. However, if your encoder only supports Zixi and you use it to deliver to a decoder which only supports SRT, it’s not going to work out. The industry as accepted that these formats should be reconciled into a shared standard. This is RIST.

File-based workflows are mainly based on TCP (Transmission Control Protocol) although, notably, some file transfer service just as Aspera are based on UDP where packet recovery, not unlike RIST, is managed as part of the the protocol. This is unlike web sites where all data is transferred using TCP which sends an acknowledgement for each packet which arrives. Whilst this is great for ensuring files are uncorrupted, it can impact arrival times which can lead to live media being corrupted.

RIST is being created by the VSF – the Video Standards Forum – who were key in introducing VS-03 and VS-04 into the AIMS group on which SMPTE ST 2022-6 was then based. So their move now into a specification for reliable transmission of media over the internet has many anticipating great things. At the point that this talk was given the simple profile has been formed. Whist Merrick gives the details, it’s worth pointing out that this doesn’t include intrinsic encryption. It can, of course, be delivered over a separately encrypted tunnel, but an intrinsic part of SRT is the security that is provided from within the protocol.

Despite Zixi, a proprietary solution, and Haivision’s open source SRT being in competition, they are both part of the VSF working group creating RIST along with VideoFlow. This is because they see the benefit of having a widely accepted, interoperable method of exchanging media data. This can’t be achieved by any single company alone but can benefit all players in the market.

This talk remains true for the simple profile which just aims to recover packets. The main protocol, as opposed to ‘simple’, has since been released and you can hear about it in a separate video here. This protocol adds FEC, encryption and other aspects. Those who are familiar with the basics may whoosh to start there.

Speaker

Merrick Ackermans Merrick Ackermans
Chair,
VSF RIST Activity Group

Video: 2019 What did I miss? – SRT

We’re looking at the most popular posts of 2019 now as The Broadcast Knowledge takes a break over the holiday season. Twitch’s Alex Converse had one of the most visited posts of the year in his video detailing how SRT works. It’s a great technical resource for developers and engineers wanting to understand more than just the highlights of SRT. Did it do well because it was Alex? Because the San Francisco’s Video Tech meet up is a well known part of Demuxed’s community for ‘engineers working with video’ or because its title? Any or all of these could be true and it wouldn’t invalidate it’s usefulness or its popularity. So if you haven’t already, read more about it here, or click play below.

Another SRT talk of interest this year you may want to catch up on was the IBC SRT Open Source Technical panel which looked at the general SRT features and looked at the pros and cons against SRT. The panel looked at a case study with Red Bee Media and South American broadcaster Globo and the use of RTP and SRT together. Read more detail here or click here to watch for free

Speaker

Alex Converse Alex Converse
Streaming Video Software Engineer,
Twitch

Video: RIST Main Profile Description

RIST solves a problem by transforming unmanaged networks into reliable paths for video contribution in an interoperable way. RIST not only improves reliability through re-requesting missing packets, but also comes with a range of features and tools, not least of which is tunnelling. Cobalt Digital’s EVP of engineering, Ciro Noronha explains how the protocol works and what’s next on the roadmap.

Ciro starts with a look at the RIST Simple Profile covering the ARQ negative acknowledgement (NACK) mechanism, link bonding and seamless switching. He then moves on to examine the missing features such as content encryption, authentication, simpler firewall configurations, in-band control, high bitrates, NULL packet extraction. These features define RIST’s Main Profile.

Tunnelling and Multiplexing is a technique to combine Simple Profile flows into a bi-directional tunnel, providing simpler network and encryption configuration. Using a GRE (RFC 8086) tunnel, RIST provides a full, protocol agnostic tunnel and a UDP-only reduced overheard mode which only requires 0.6% data overhead to implement. Ciro explains a number of setups, including one where the connection is initiated by the receiver – something that the Simple Profile doesn’t allow.

Authentication and Encryption are covered next. DTLS us the UDP implementation of TLS which is the security mechanism used on secure websites. This provides security to the tunnel so everything which travels through is covered. Ciro explains the pre-shared key (PSK) mechanism in the Main Profile.

The talk finishes by covering NULL Packet removal, also known as ‘bandwidth optimisation’, header extension which extends RTP’s sequence number to allow for more in-flight packets and questions from the audience.

Watch now!
Speaker

Ciro Noronha Dr. Ciro Noronha
Executive Vice President of Engineering,
Cobalt Digital