Video: SCTE 224? ESNI? What is Everyone Talking About?

Ad insertion with SCTE 35 is common enough in streaming today, but it can be a blunt tool when it comes to running a complex service which requires complex scheduling and switching plus more detailed control of advert playback and geographical deployment. SCTE 224 is here to meet the challenge by increasing the range of metadata that can be signalled.

Stuart Kurkowski from Comcast explains this need for SCTE 224 and what it delivers. For instance, a lot of SCTE 224 is devoted to controlling the US-style blackouts where viewers close to a sports game can’t watch the game live on TV. Whilst this is relatively easy to deal within the US for local terrestrial transmitters, in OTT, this is a new ability. But SCTE 224, however, isn’t just able blackouts. It also transmits accurate, multi-level, schedule information which helps to schedule complex ad breaks providing detailed, frame-accurate, local ad insertion.

It shouldn’t be thought that SCTE 35 and SCTE 224 are mutually exclusive. SCTE 35 can provide very accurate updates to unscheduled programmes and delays, where the 224 information still carries the rich metadata.

Find out more in this short primer!/a>
Speakers

Stuart Kurkowski Stuart Kurkowski
Distinguished Engineer and Principal Architect,
Comcast Technology Solutions

Video: DASH: from on-demand to large scale live for premium services

A bumper video here with 7 short talks from VideoLAN, Will Law and Hulu among others, all exploring the state of MPEG DASH today, the latest developments and the hot topics such as low latency, ad insertion, bandwidth prediction and one red letter feature of DASH – multi-DRM.

The first 10 minutes sets the scene introducing the DASH Industry Forum (DASH IF) and explaining who takes part and what it does. Thomas Stockhammer, who is chair of the Interoperability Working Group explains that DASH IF is made of companies, headline members including Google, Ericsson, Comcast and Thomas’ employer Qualcomm who are working to promote the adoption MPEG-DASH by working to imrove the specification, advise on how to put it into practice in real life, promote interoperability, and being a liaison point for other standards bodies. The remaining talks in this video exemplify the work which is being done by the group to push the technology forward.

Meeting Live Broadcast Requirements – the latest on DASH low latency!
Akamai’s Will Law takes to the mic next to look at the continuing push to make low-latency streaming available as a mainstream option for services to use. Will Law has spoken about about low latency at Demuxed 2019 when he discussed the three main file-based to deliver low latency DASH, LHLS and LL-HLS as well as his famous ‘Chunky Monkey’ talk where he explains how CMAF, an implementation of MPEG-DASH, works in light-hearted detail.

In today’s talk, Will sets out what ‘low latency’ is and revises how CMAF allows latencies of below 10 seconds to be achieved. A lot of people focus on the duration of the chunks in reducing latency and while it’s true that it’s hard to get low latency with 10 second chunk sizes, Will puts much more emphasis on the player buffer rather than the chunk size themselves in producing a low-latency stream. This is because even when you have very small chunk sizes, choosing when to start playing (immediately or waiting for the next chunk) can be an important part of keeping the latency down between live and your playback position. A common technique to manage that latency is to slightly increase and decrease playback speed in order to manage the gap without, hopefully, without the viewer noticing.

Chunk-based streaming protocols like HLS make Adaptive Bitrate (ABR) relatively easy whereby the player monitors the download of each chunk. If the, say, 5 second chunk arrives within 0.25 seconds, it knows it could safely choose a higher-bitrate chunk next time. If, however the chunk arrives in 4.8 seconds, it can choose to the next chunk to be lower-bitrate so as to receive the chunk with more headroom. With CMAF this is not easy to do since the segments all arrive in near real-time since the transferred files represent very small sections and are sent as soon as they are created. This problem is addressed in a later talk in this talk.

To finish off, Will talks about ‘Resync Elements’ which are a way of signalling mid-chunk IDRs. These help players find all the points which they can join a stream or switch bitrate which is important when some are not at the start of chunks. For live streams these are noted in the manifest file which Will walks through on screen.

Ad Insertion in Live Content:Pre-, Mid- and Post-rolling
Whilst not always a hit with viewers, ads are important to many services in terms of generating the revenue needed to continue delivering content to viewers. In order to provide targeted ads, to ensure they are available and to ensure that there is a record of which ads were played when, the ad-serving infrastructure is complex. Hulu’s Zachary Cava walks us through the parts of the infrastructure that are defined within DASH such as exchanging information on ‘Ad Decision Parameters’ and ad metadata.

In chunked streams, ads are inserted at chunk boundaries. This presents challenges in terms of making sure that certain parameters are maintained during this swap which is given the general name of ‘Content Splice Conditioning.’ This conditioning can align the first segment aligned with the period start time, for example. Zachary lays out the three options provided for this splice conditioning before finishing his talk covering prepared content recommendations, ad metadata and tracking.

Bandwidth Prediction for Multi-bitrate Streaming at Low Latency
Next up is Comcast’s Ali C. Begen who follows on from Will Law’s talk to cover bandwidth prediction when operating at low-latency. As an example of the problem, let’s look at HTTP/1.1 which allows us to download a file before it’s finished being written. This allows us to receive a 10-second chunk as it’s being written which means we’ll receive it at the same rate the live video is being encoded. As a consequence the time each chunk takes to arrive will be the same as the real-time chunk duration (in this example, 10 seconds.) When you are dealing with already-written chunks, your download time will be dependent on your bandwidth and therefore the time can be an indicator of whether your player should increase or decrease the bitrate of the stream it’s pulling. Getting back this indicator for low-latency streams is what Ali presents in this talk.

Based on this paper Ali co-authored with Christian Timmerer, he explains a way of looking at the idle time between consecutive chunks and using a sliding window to generate a bandwidth prediction.

Implementing DASH low latency in FFmpeg
Open-source developer Jean-Baptiste Kempf who is well known for his work on VLC discusses his work writing an MPEG-DASH implementation for FFmpeg called the DASH-LL. He explains how it works and who to use it with examples. You can copy and paste the examples from the pdf of his talk.

Managing multi-DRM with DASH
The final talk, ahead of Q&A is from NAGRA discussing the use of DRM within MPEG-DASH. MPEG-DASH uses Common Encryption (CENC) which allows the DASH protocol to use more than one DRM scheme and is typically seen to allow the use of ‘FairPlay’, ‘Widevine’ and ‘PlayReady’ encryption schemes on a single stream dependent on the OS of the receiver. There is complexity in having a single server which can talk to and negotiate signing licences with multiple DRM services which is the difficulty that Lauren Piron discusses in this final talk before the Q&A led by Ericsson’s VP of international standards, Per Fröjdh.

Watch now!
Speakers

Thomas Stockhammer Thomas Stockhammer
Director of Technical Standards,
Qualcomm
Will Law Will Law
Chief Architect,
Akamai
Zachary Cava Zachary Cava
Software Architect,
Hulu
Ali C. Begen Ali C. Begen
Technical Consultant, Video Architecture, Strategy and Technology group,
Comcast
Jean-Baptiste Kempf Jean-Baptiste Kempf
President & Lead VLC Developer
VideoLAN
Laurent Piron Laurent Piron
Principal Solution Architect
NAGRA
Per Fröjdh Moderator: Per Fröjdh
VP International Standards,
Ericsson

Video: Harness SSAI’s Superpowers

Server-side Ad Insertion (SSAI) is a great option for streaming services delivering video to a wide variety of devices and for those who need to avoid ad blockers. Whilst ad insertion can happen in the player, this mechanism can be interfered with allowing users to avoid ads. Whilst client-side ad insertion can much more easily create a unique stream for each client, dynamic SSAI can now do the same with a better user experience.

This panel from the OTT Leadership Summit at Streaming Media West 2019 brings together Disney, WarnerMerdia and Crunchyroll to share their experiences with SSAI. They discuss beaconing, ad standards, scaling, SCTE and more.

Beaconing goes hand in hand with ad playback providing metrics on what happened. When you perform certain actions, the player will reach out to a URL. This can be used to indicate such things as users skipping or pausing a video. The beacon information can then be used to verify how much of which ads were seen by whom and charge advertisers accordingly.

The panel moves on to discussing scaling using live sports as an example and cover questions to ask vendors to ensure you and they are ready for maximum scale. Bandwidth, is declared the biggest challenge, but a less obvious problem is that your upstream ad providers can’t always scale well. If you rely on calls from your server to others, then it’s vital to understand their scaling capacity and strategy. They discuss issues with losing beacons when operating at scale and the need for detailed logging and debugging in order to spot errors and reconcile the results.

Some time is next spent on VPAID and VAST 4 which are both messaging specifications to allow ad servers to tell applications which ads to play. The panel discusses the pros and cons in their use for SSAI where the stitcher needs to reach out to and ad server in real time to find out which ads to play.

At the end of the discussion, the panel takes questions from the floor but not before discussing SCTE Markers and ‘content conditioning’ which surrounds taking care of your source videos and encoder such that the two assets fit together properly at I-frame boundaries.

Watch now!
Speakers

Robert Jameson Robert Jameson
Technical Director, Media Enablement
Turner | WarnerMedia
Stephen Gray Stephen Gray
Director, Ad Tech Systems
Walt Disney Direct-to-Consumer & International
Michael Dale Michael Dale
VP Engineering,
Crunchyroll
Nadine Krefetz Nadine Krefetz
Consultant, Reality Software
Contributing Editor, Streaming Media

Video: Simplifying OTT Video Delivery With SCTE 224

Life used to be simple; you’d fire up your camera, point it at a presenter and it would be fed to the transmitter network. When on-going funding came into play, we wanted each transmitter to be able to show local ads and so, after many years, SCTE-35 was born to do exactly that. In today’s world, however, simply telling a transmitter when to switch doesn’t cut it. To deliver the complex workflows that both linear and OTT delivery demand, SCTE 224 has arrived on the scene which provides very comprehensive scheduling and switching.

Jean Macher, from Harmonic explains this need for SCTE 224 and what it delivers. For instance, a lot of SCTE 224 is devoted to controlling the US-style blackouts where viewers close to a sports game can’t watch the game live. Whilst this is relatively easy to deal within the US for local terrestrial transmitters, in OTT, this is a new ability. Traditionally, geo-location of IP addresses is needed for this to work where each IP address is registered against a provider. If this provider is Chinese, then at the very least, you should be able to say that this IP address is in China. However, for ISPs who have an interest in the programming, they can bring in to effect their own data in order to have very accurate geolocation data.

SCTE 224, however, isn’t just able blackouts. It also transmits accurate, multi-level, schedule information which helps to schedule complex ad breaks providing detailed, frame-accurate, local ad insertion.

It shouldn’t be thought that SCTE 35 and SCTE 224 are mutually exclusive. SCTE 35 can provide very accurate updates to unscheduled programmes and delays, where the 224 information still carries the rich metadata.

To finish up the talk, Jean looks at a specific example of the implementation and how SCTE 224 has been updated in recent years.

Watch now!

Speakers

Jean Macher Jean Macher
Director, Market Development – Broadcast
Harmonic Inc.