Video: Pervasive video deep-links

Google have launched a new initiative allowing publishers to highlight key moments in a video so that search results can jump straight to that moment. Whether you have a video that looks at 3 topics, one which poses questions and provides answers or one which has a big reveal and reaction shots, this could help increase engagement.

The plan is the content creators tell Google about these moments so Paul Smith from theMoment.tv takes to the stage at San Francisco Video Tech to explain how. After looking at a live demo, Paul takes a dive into the webpage code that makes it happen. Hidden in the tag, he shows the script which has its type set to application/ld+json. This holds the metadata for the video as a whole such as the thumbnail URL and the content URL. However it also then defines the highlighted ‘parts’ of the video with URLs for those.

Whiles the programme is currently limited to a small set of content publishers, everyone can benefit from these insights on google video search. It will also look at YouTube descriptions in which some people give links to specific times such as different tracks in a music mix, and bring those into the search results.

Paul looks at what this means for website and player writers. On suggestion is the need to scroll the page to the correct video and make the different videos on a page clearly signposted. Paul also looks towards the future at what could be done to better integrate with this feature. For example updating the player UI to see and create moments or improve the ability to seek to sub-second accuracy. Intriguingly he suggests that it may be advantageous to synchronise segment timings with the beginning of moments for popular video. Certainly food for thought.

Watch now!
Speaker

Paul Smith Paul Smith
Founder,
theMoment.tv

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: SRT – How the hot new UDP video protocol actually works under the hood

In the west, RTMP is seen as a dying protocol so the hunt is on for a replacement which can be as widely adopted but keep some of it’s best parts including relatively low latency. SRT is a protocol for Secure, Reliable Transport of streams over the internet so does this have a role to play and how does it work?

Alex Converse from Twitch picks up the gauntlet to dive deep into the workings of SRT to show how it compares to RTMP and specifically how it improves upon it.

RTMP fails in many ways, two to focus on are that the spec has stopped moving forward and it doesn’t work well over problematic networks. So Alex takes a few minutes to explain where SRT has come from, the importance of t being open source and how to get hold of the code and more information.

Now, Alex starts his dive into the detail reminding us about UDP, TS Packets and Ethernet MTUs has he goes down. We look at how SRT data packets are formed which helps explain some of the features and sets us up for a more focussed look.

SRT, as with other, similar protocols which create their resilience by retransmitting missing packets, need to use buffers in order to have chance to send the missing data before it’s needed at the decoder. Alex takes us through how the sender and receiver buffers work to understand the behaviour in different situations.

Fundamental to the whole protocol is packet the packet acknowledgement and negative acknowledgements which feature heavily before we discuss handshaking as we start our ascent from the depths of the protocol. As much as acknowledgements provide the reliability, encryption provides the ‘secure’ in Secure Reliable Transport. We look at the approach taken to encryption and how it relates to current encryption for websites.

Finally Alex answers a number of questions from the audience as he concludes this talk from the San Francisco Video Tech meet up.

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Speaker

Alex Converse Alex Converse
Streaming Video Software Engineer,
Twitch

Video: How Libre Can you Go?


Many companies would love to be using free codecs, unencumbered by patents, rather than paying for HEVC or AVC. Phil Cluff shows that, contrary to popular belief, it is possible stream with free codecs and get good coverage on mobile and desktop.

Phil starts off by looking at the codecs available and whether they’re patent encumbered with an eye to how much of the market can actually decode them. Free codecs and containers like WebM, VP8 etc. are not supported by Safari which reduces mobile penetration by half. To prove the point, Phil presents the results of his trials in using HEVC, AVC and VP8 on all major browsers.

Whilst this initially leaves a disappointing result for streaming with libre codecs on mobile, there is a solution! Phil explains how an idea from several years ago is being reworked to provide a free streaming protocol MPAG-SASH which avoids using DASH which is itself based on ISO BMFF which is patent encumbered. He then explains how open video players like video.js can be modified to decode libre codecs.

With these two enhancements, we finally see that coverage of up to 80% on mobile is, in principle, possible.

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Speakers

Phil Cuff Phil Cluff
Streaming Specialist,
Mux