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Video: The Past, Present and Future of AV1

Posted on 15th August 2019 by Russell Trafford-Jones

AV1 has strong backing from tech giants but is still seldom seen in the wild. Find out what the plans are for the future with Google’s Debargha Mukherjee.

Debargha’s intent in this talk is simple: to frame a description of what AV1 can do and is doing today in terms of the history of the codec and looking forward to the future and a potential AV2.

The talk starts by demonstrating the need for better video codecs not least of which is the statistic that by 2021, 81% of the internet’s traffic is expected to be video. But on top of that, there is a frustration with the slow decade-long refresh process which is traditional for video codecs. In order to match the new internet landscape with fast-evolving services, it seemed appropriate to have a codec which, not only delivered better encoding but also saw a quicker five-year refresh cycle.

As a comparison to the royalty-free AV1, Debargha then looks at VP9 it is deployed. Furthermore, VP10 who’s development was stopped and diverted into the AV1 effort which is then the topic for the next part of the talk; the Alliance for Open Media, the standardisation process and then a look at some of the encoding tools available to archive the stated aims.

To round off the description of what’s presently happening with AV1 trials of VP9, HEVC and AV1 are shown demonstrating AV1s ability to improve compression for a certain quality. Bitmovin and Facebook’s tests are also highlighted along with speed tests.

Looking, now, to the future, the talk finishes by explaining the future roadmap for hardware decoding and other expected milestones in the coming years plus the software work such as SVT-AV1 and DAV1D for optimised encoding and decoding. With the promised five-year cycle, we need to look forward now to AV2 and Debargha discusses what it might be and what it would need to achieve.

Watch now!
Speaker

Debargha Mukherjee
Principal Software Engineer,
Google

Video: A Study of Protocols for Low Latency Video Transport Over the Internet

Posted on 21st June 2019 by Russell Trafford-Jones

Contribution via the internet is tricky but has great promise. With packet loss and jitter all over the place, how can you deliver perfect video?

Ciro Noronha from Cobalt Digital explains the two ways people get around the unreliability of the internet: FEC and retransmission. Forward Error Correction uses some maths to transmit extra data on top of the stream which allows the receiver to correct for any packet losses. This method is standard in satellite transmission where it is always used to add robustness.

Retransmission is different in that it requires a return channel. When a receiver spots a missing packet, it asks for it to be resent. Being that it has to wait for a reply, retransmission protocols like SRT, ARQ and RIST run with a configurable buffer which needs to be big enough for at least one round trip. FEC schemes also require a buffer as it needs to wait for a number of packets before it can complete the maths required.

Ciro introduces FEC and ARQ before presenting work showing experiments he’s run on both FEC and ARQ to see the limits of their signal-correcting capabilities and latency. He finishes explaining what RIST is and its status.

Bring yourself up to date with RIST!
Watch now!

Speaker

Ciro Noronha
Director of Technology,
Cobalt Digital

Video: Performance Measurement Study of RIST

Posted on 23rd May 2019 by Russell Trafford-Jones

RIST solves a problem by transforming unmanaged networks into reliable paths for video contribution. This comes amidst increasing interest in using the public internet to contribute video and audio. This is partly because it is cheaper than dedicated data circuits, partly that the internet is increasingly accessible from many locations making it convenient, but also when feeding cloud-based streaming platforms, the internet is, by definition, part of the signal path.

Packet loss and packet delay are common on the internet and there are only two ways to compensate for them: One is to use Forward Error Correction (FEC) which will permanently increase your bandwidth by up to 25% so that your receiver can calculate which packets were missing and re-insert them. Or your receiver can ask for the packets to be sent again.
RIST joins a number of other protocols to use the re-request method of adding resilience to streams which has the benefit of only increasing the bandwidth needed when re-requests are needed.

In this talk, Ciro Noronha from Cobalt Digital, explains that RIST is an attempt to create an interoperable protocol for reliable live streaming – which works with any RTP stream. Protocols like SRT and Zixi are, to one extent or another, proprietary – although it should be noted that SRT is an open source protocol and hence should have a base-level of interoperability. RIST takes interoperability one stage further and is seeking to create a specification, the first of which is TR-06-1 also known as ‘Simple Profile’.

We then see the basics of how the protocol works and how it uses RTCP for singling. Further more RIST’s support for bonding is explored and the impact of packet reordering on stream performance.

The talk finishes with a look to what’s to come, in particular encryption, which is an important area that SRT currently offers over and above reliable transport.
Watch now!

To dig into SRT, check out this talk from Chris Michaels
For more on RIST, have a look at Kieran Kunhya’s talk and Rick Ackerman’s introduction to RIST.

Speaker

Ciro Noronha
Director of Technology, Compression Systems,
Cobalt Digital

Webinar: What to See at NAB

Posted on 21st March 2019 by Russell Trafford-Jones

Date: Friday, March 29th 2019
Time: 11am PT / 2pm ET / 18:00 GMT

NAB is coming around again and the betting has started on what the show will bring. Whilst we can look to last year for hints, here editors from Streaming Media come together to discuss the current trends in the industry and how they will be represented at NAB.

Some highlights of the conversation will be:

What HEVC solutions people are showing – the ongoing codec wars are captivating to most people as AV1 tries – and gradually succeeds – to break its ‘too slow’ label, whilst HEVC continues to grow acceptance with its ‘ready to deploy’ label despite the fees.
UHD production and delivery – We know that production houses prefer to capture higher resolution as it increases the value of their content and gives them more options in editing. But how far is UHD developing further down the chain. Is it just for live sports?
Live Streaming – SRT is bound to keep making waves at NAB has Haivision plans its biggest event yet discussing the many ways it’s being used. SRT delivers encrypted, reliable streams – while there are competitors, SRT continues to grow apace.
NDI – This compressed but ultra low latency codec continues to impress for live production workflows – particularly live events, though it’s not clear how much – if at all – it will make its way into top-tier broadcasters.

Much more will be on the cards, so register now for this session on Friday March 29th.

Speakers

	Troy Dreier Senior Editor, Streaming Media
	Steve Nathans-Kelly Editor Streaming Media
	Eric Schumacher-Rasmussen VP & Editor-in-Chief Streaming Media