Low latency Archives – Page 7 of 14 – The Broadcast Knowledge

Video: Introducing Low-Latency HLS

Posted on 14th November 2019 by Russell Trafford-Jones

HLS has taken the world by storm since its first release 10 years ago. Capitalising on the already widely understood and deployed technologies already underpinning websites at the time, it brought with it great scalability and the ability to seamlessly move between different bitrate streams to help deal with varying network performance (and computer performance!)

HLS has continued to evolve over the years with the new versions being documented as RFC drafts under the IETF. Its biggest problem for today’s market is its latency. As originally specified, you were guaranteed at least 30 seconds latency and many viewers would see a minute. This has improved over the years, but only so far.

Low-Latency HLS (LL-HLS) is Apple’s answer to the latency problem. A way of bringing down latency to be comparable with broadcast television for those live broadcast where immediacy really matters.

Please note: Since this video was recorded, Apple has released a new draft of LL-HLS. As described in this great article from Mux, the update’s changes are

“Delivering shorter sub-segments of the video stream (Apple call these parts) more frequently (every 0.3 – 0.5s)

Using HTTP/2 PUSH to deliver these smaller parts, pushed in response to a blocking playlist request

Blocking playlist requests, eliminating the current speculative manifest request polling behaviour in HLS

Smaller, delta rendition playlists, which reduces playlist size, which is important since playlists are requested more frequently

Faster rendition switching, enabled by rendition reports, which allows clients to see what is happening in another playlist without requesting it in its entirety”[0]

Read the full article for the details and implications, some of which address some points made in the talk.

Furthermore, THEOplayer have released this talk explaining the changes and discussing implementation.

This talk from Apple’s HLS Technical Lead, Roger Pantos, given at Apple’s WWDC conference this year goes through the problems and the solution, clearly describing LL-HLS. Over the following weeks here on The Broadcast Knowledge we will follow up with some more talks discussing real-world implementations of LL-HLS, but to understand them, we really need to understand the fundamental proposition.

Apple has always been the gatekeeper to HLS and this is one reason the MPEG DASH exists; a streaming standard that is separate to any one corporation and has the benefits of being passed by a standards body (MPEG). So who better to give the initial introduction.

HLS is a chunk-based streaming protocol meaning that the illusion of a perfect stream of data is given by downloading in quick succession many different files and it’s the need to have a pipeline of these files which causes much of the delay, both in creating them and in stacking them up for playback. LL-HLS uses techniques such as reducing chunk length and moving only parts of them in order to drastically reduce this intrinsic latency.

Another requirement of LL-HLS is HTTP/2 which is an advance on HTTP bringing with it benefits such as having multiple requests over a single HTTP connect thereby reducing overheads and request pipelining.

Roger carefully paints the whole picture and shows how this is intended to work. So while the industry is still in the midst of implementing this protocol, take some time to understand it from the source – from Apple.

Watch now!
Download the presentation

Speaker

Roger Pantos
HLS Technical Lead,
Apple

Video: Understanding esports production

Posted on 29th October 2019 by Russell Trafford-Jones

Esports is here to stay and brings a new dimension on big events which combine the usual challenges of producing and broadcasting events at scale with less usual challenges such as non-standard resolutions and frame rates. This session from the IBC 2019 conference looks at the reality of bringing such events to life.

The talk starts with a brief introduction to some Esports-only terms before heading into the discussions starting with Simon Eicher who talks about his switch toward typical broadcast tools for Esports which has helped drive better production values and story telling. Maxwell Trauss from Riot Games explains how they incubated a group of great producers and were able keep production values high by having them working on shows remotely worldwide.

Blizzard uses the technique of using a clean ‘world feed’ which is shared worldwide for regions to regionalise it with graphics and language before then broadcasting this to the world. In terms of creating better storytelling, Blizzard have their own software which interprets the game data and presents it in a more consumable way to the production staff.

Observers are people who control in-game cameras. A producer can call out to any one of the observers. The panel talks about how separating the players from the observers from the crowd allows them to change the delay between what’s happening in the game and each of these elements seeing it. At the beginning of the event, this creates the opportunity to move the crowd backwards in time so that players don’t get tipped off. Similarly they can be isolated from the observers for the same effect. However, by the end of the game, the delays have been changed to bring everyone back into present time for a tense finale.

Corey Smith from Blizzard explains the cloud setup including clean feeds where GFX is added in the cloud. This would lead to a single clean feed from the venue, in the end. ESL, on the other hand choose to create their streams locally.

Ryan Chaply from Twitch explains their engagement models some of which reward for watching. Twitch’s real-time chat banner also changes the way productions are made because the producers have direct feedback from the viewers. This leads, day by day, to tweaks to the formats where a production may stop doing a certain thing by day three if it’s not well received, conversely when something is a hit, they can capitalise on this.

Ryan also talks about what they are weighing up in terms of when they will start using UHD. Riot’s Maxwell mentions the question of whether fans really want 4K at the moment, acknowledging it’s an inevitability, he asks whether the priority is actually having more/better stats.

The panel finishes with a look to the future, the continued adoption of broadcast into Esports, timing in the cloud and dealing with end-to-end metadata and a video giving a taste of the Esports event.

Watch now!
Speakers

	Simon Eicher Executive Producer, Director of Broadcast, eSports Services, ESL
	Ryan Chaply Senior Esports Program Manager, Twitch
	Corey Smith Director, Live Operations Broadcast Technology Group, Blizzard
	Maxwell Trauss Broadcast Architect, Riot Games
	Jens Fischer Global Esport Specialist and Account Manager D.A.CH, EVS

Video: Streaming Live Events: When it must be alright on the night

Posted on 20th September 2019 by Russell Trafford-Jones

Live Streaming is an important part of not only online viewing, but increasingly of broadcast in general. It’s well documented that live programming is key to keeping linear broadcast’s tradition of ‘everyone watching at once’ which has been diluted – for both pros and cons – by non-linear viewing in recent years.

This panel, as part of IBC’s Content Everywhere, looks at the drivers behind live streaming, how it’s evolving and its future. Bringing together ultra-low-latency platform nanocosmos with managed service provider M2A Media and video player specialists Visual On, Editor of The Broadcast Knowledge, Russell Trafford-Jones starts the conversation asking what gamification is and how this plays in to live streaming.

nanocosmos’s Oliver Lietz explains how gamification is an increasing trend in terms of not only monetising existing content but is a genre in and of itself providing content which is either entirely a game or has a significant interactive element. With such services, it’s clear that latency needs to be almost zero so his company’s ability to deliver one-second latency is why he has experience in these projects.

We hear also from VisualOn’s Michael Jones who explains the low-latency service they were involved in delivering. Here, low-latency CMAF was used in conjunction with local synced-screen technology to ensure that not only was latency low, but second screen devices were not showing video any earlier/later than the main screen. The panel then discussed the importance of latency compared to synchronised viewing and where ultra-low latency was unnecessary.

Valentijn Siebrands from M2A talks about the ability to use live streaming and production in the cloud to deliver lower-cost sports events but also deliver new types of programming. Valentijn then takes us into the topic of analytics, underlining the importance of streaming analytics which reveal the health of your platform/infrastructure as much as the analytics which are most usually talked about; those which tell you the quality of experience your viewers are having and their activities on your app.

The talk concludes with a look to the future, talking about the key evolving technologies of the moment and how they will help us move forward between now and IBC’s Content Everywhere Hub in 2021.

Watch now!

Speakers

	Oliver Lietz CEO & Founder, nanocosmos
	Michael Jones Former SVP and Head of Business Development, VisualOn Inc
	Valentijn Siebrands Solutions Architect, M2A Media
	Russell Trafford-Jones – Moderator Manager, Support & Services – Techex Executive Member – IET Media Technical Network

Video: The Evaluation Process of Ultra Low-Latency Solutions

Posted on 5th September 2019 by Russell Trafford-Jones

Patrick Debois summarises the world of low-latency players from his perspective of wanting to deploy his own solution.

Low- and ultra low-latency is an emerging market in the sense that there are few standards and getting the solutions working at scale and across all platforms is difficult and is a ‘work in progress’. As such, selecting a player is a compromise and there are many issues at play.

Patrick covers the following aspects: