Video

Video: RIST – an evolutionary video transport protocol

Posted on by Russell Trafford-Jones

Delivering low-latency live-video over the public internet, or any network which sees packet loss is ever a challenge, but recently there have been a number of protocols which have been created to allow this to work.

The problem to be fixed is that packets get lost and when you have a video decoder trying to output 50 images every second, there really isn’t time to deal with missing packets. Protocols such as SRT, Zixi and, now, RIST allow a mechanism which adds a small buffer and a mechanism to request missing data.

This isn’t a problem, in general, for live streaming to consumers on devices or computers such as Netflix or iPlayer because they use HLS or similar protocols based on TCP, but for low-latency streams this is not practical.

In this talk Kieran Kunhya explains more about these basics, the challenges to be overcome and the ways of dealing with them.

He covers:

  • UDP & TCP.
  • RIST and other similar protocols
  • Retransmissions
  • Negative Acknowledgements
  • Implementations of RIST
  • Future plans for RIST
  • A live demo

Watch now!

Speaker

Kieran Kunhya Kieran Kunhya
Founder,
Open Broadcast Systems

Video: Scalable Video Coding in HEVC & AV1

Posted on by Russell Trafford-Jones

While it has never played a big role in practical applications, scalable video coding has been around since the times of MPEG 2, and might actually have some advantages over the multi-rate transmission often applied today. The purpose of scalable coding is to efficiently compress multiple different versions of the same video in one “scalable” bitstream. Actually this sounds like the perfect solution for VOD and streaming applications, but unfortunately it has some downsides and few vendors ever used it. In this talk, Chrstian will review the basic idea of scalable coding, how it is enabled in modern coding standards and the pros and cons of implementing the technology in streaming applications.

Speaker

Christian Feldmann Chrisitan Feldmann
Codec Engineer,
Bitmovin

Video: AES67 Open Media Standard for Pro-Audio Networks

Posted on by Russell Trafford-Jones

AES67 is a method of sending audio over IP which was standardised by the Audio Engineering Society as a way of sending uncompressed video over networks between equipment. It’s become widespread and is part of SMPTE’s professional essences-over-IP standards suite, ST 2110.

Here, Conrad Bebbington gives us an introduction to AES67 explaining why AES67 exists and what it tries to achieve. Conrad then goes on to look at interoperability with other competing standards like Dante. After going into some implementation details, importantly, the video then looks the ‘Session Description Protocol’, SDP, and ‘Session Initialisation Protocol’, SIP which are important parts of how AES67 works.

Other topics covered are:

  • Packetisation – how much audio is in a packet, number of channels etc.
  • Synchronisation – using PTP
  • What are SDP and SIP and how are they used
  • Use of IGMP multicast
  • Implementation availability in open source software

Watch now!

For a more in-depth look at AES67, watch this video

Speakers

Conrad Bebbington Conrad Bebbington
Software Engineer,
Cisco

Video: Designing and Utilising SMPTE 2110 for Broadcast: Opportunities and Challenges

Posted on by Russell Trafford-Jones

A meeting of experienced minds here at the Pittsburgh SMPTE section talking about the opportunities and challenges of ST-2110. Phil Myers from Lawo talks optimistically about the challenges that can and often have been solved in implementing 2110 whether that be network infrastructure or timing, giving a good primer on the whole topic as he starts the session.

Hugo Gaggioni from Sony, talks about NMOS, explaining what AMWA does and the difference between their IS-04,05 and 06 specifications.

Karl Kuhn from Tektronix then discusses packet pacing, PTP and network architectures. He then looks at how to monitor PTP and see it is working well.

With the panel session at the end, joined by Dan Turk from NEP, there is a free-ranging discussion covering some of the following topics:

  • Control of IP networks
  • The limits of IP
  • Multicast traffic
  • Network Architecture
  • True non-blocking switches
  • Break-even points of IP systems
  • Split essences & dropping blanking
  • Network planning for UHD
  • Handling loss of network on PTP implementations
    plus much more!

Watch now!

Speakers

Phil Myers Phil Myers
Senior Director, IP Systems,
Lawo
Karl Kuhn Karl Kuhn
Senior Field Video Applications Engineer,
Tektronix
Hugo Gaggioni Hugo Gaggioni
CTO, Broadcast and Production Systems Division
Sony
Dan Turk Dan Turk
Chief Engineer, Mobile Units
NEP