There are so many ways to stream video, how can you find the one that suits you best? Weighing up the pros and cons in this talk is Robert Reindhardt from videoRx.
Taking each of the main protocols in turn, Robert explains the prevalence of each technology from HLS and DASH through to WebRTC and even Websockets. Commenting on each from his personal experience of implementing each with clients, we build up a picture of when the best situations to use each of them.
Manipulating the manifest of streamed video allows localisation of adverts with the option of per-client customisation. This results in better monetisation but also a better way to deal with blackouts and other regulatory or legal restrictions.
Using the fact that most streamed video is delivered by using a playlist which is simply a text file which lists the locations of the many files which contain the video, we see that you could deliver different playlists to clients in different locations – detected via geolocating the IP address. Similarly different ads can be delivered depending on the type of client requesting – phone, tablet, computer etc.
Here, Imagine’s Yuval Fisher starts by reminding us how online streaming typically works using HLS as an example. He then leads us through the possibilities of manifest manipulation. One interesting idea is using this to remove hardware delivering cost savings using the same infrastructure to deliver to both the internet and broadcast. Yuval finshes up with a list of “Dos and Don’ts” to explain the best way to achieve the playlist manipulation.
Sarah Foss rounds off the presentation explaining how manifest manipulation sits at the centre of the rest of the ad-delivery system.
Streaming on the net relies on delivering video at a bandwidth you can handle. Called ‘Adaptive Bitrate’ or ABR, it’s hardly possible to think of streaming without it. While the idea might seem simple initially – just send several versions of your video – it quickly gets nuanced.
Streaming experts Streamroot take us through how ABR works at Streaming Media East from 2016. While the talk is a few years old, the facts are still the same so this remains a useful talk which not only introduces the topic but goes into detail on how to implement ABR.
The most common streaming format is HLS which relies on the player downloading the video in sections – small files – each representing around 3 to 10 seconds of video. For HLS and similar technologies, the idea is simply to allow the player, when it’s time to download the next part of the video, to choose from a selection of files each with the same video content but each at a different bitrate.
Allowing a player to choose which chunk it downloads means it can adapt to changing network conditions but does imply that each file has contain exactly the same frames of video else there would be a jump when the next file is played. So we have met our first complication. Furthermore, each encoded stream needs to be segmented in the same way and in MPEG, where you can only cut files on I-frame boundaries, it means the encoders need to synchronise their GOP structure giving us our second complication.
These difficulties, many more and Streamroot’s solutions are presented by Erica Beavers and Nikolay Rodionov including experiments and proofs of concept they have carried out to demonstrate the efficacy.
Will Law from Akamai proves his chunky credentials by telling us how to achive very low-latency streaming in his talk at Demuxed 2018.
In the jungle of solutions for low latency live streaming, there are many current options ranging from WebRTC, to proprietary UDP protocols to standard segmented media with ever-shortening segments. This session highlights one of these – chunked-encoded chunked-transferred CMAF – as a optimal and practical confluence of both reach and performance. On the technical side we’ll investigate the underlying technology, the latency regimes possible, compatibility with legacy players, cachability on delivery networks and player behavior requirements. Including live demonstrations of several streams on a production network. This talks brings a standards perspective from DVB and DASH as well as CDN support. As a sweetener, Will points you at open source code on both the encoder and player side for doing this all yourself.
Chief Architect, Media Cloud Engineering