Per-title encoding with machine learning is the topic of thie video from MUX.
Nick Chadwick explains that rather than using the same set of parameters to encode every video, the smart money is to find the best balance of bitrate and resolution for each video. By analysing a large number of combinations of bitrate and resolution, Nick shows you can build what he calls a ‘convex hull’ when graphing against quality. This allows you to find the optimal settings.
Doing this en mass is difficult, and Nick spends some time looking at the different ways of implementing it. In the end, Nick and data scientist Ben Dodson built a system which optimses bitrate for each title using neural nets trained on data sets. This resulted in 84% of videos looking better using this method rather than a static ladder.
From event to event it’s not a surprise that streaming traffic increases, but this look at the Wolrd Cup 2018 shows a very sharp rise beating many expecatations. Joachim Hengge tells us what hte World Cup looked like from Akamai’s perspective.
Joachim takes us through the stats for streaming the World Cup where they peaked at 23Tbps of throuhgput with nearly 10 million concurrent viewers. The bandwidth was significantly higher than the last World Cup but looking at the data, we can learn a few more things about the market.
After looking at a macth-by-match breakdown we look at a sytsem architecture for one customer who delivered the World Cup to highlight the importance of stable content ingest, latency and broadcast quality. Encoding and packaging into HLS with 4-second chunks were tasks done on site with the rest happening within Akamai and being fed to other CDNs. Joachim pulls this together into three key recommendations for anyone looking at streaming large events before delvingin to some Sweden-specific streaming stats where over 81% of feeds were played back at the highest quality.
This talk is from Streaming Tech Sweden, an annual conference run by Eyevinn Technology. Videos from the event are available to paid attendees but are released free of charge after several months. As with all videos on The Broadcast Knowledge, this is available free of charge after registering on the site.
Senior Product Manager, Media Services,
As HDR continues its slow march into use, its different forms both in broadcast and streaming can be hard to keep track of and even differentiate. This talk from the Seattle Video Tech meetup aims to tease out these details.
Brian Alvarez from Aamzon Prime Video starts with a very brief look at how HDR has been created to sit on top of the existing distribution formats: HLS, DASH, HEVC, VP9, AV1, ATSC 3.0 and DVB. The way it does this is in a form based on either HLG or PQ.
Brian takes some time to discuss the differences between the two approaches to HDR. First off, he looks at HLG which is an ARIB standard freely available, though still with licencing. This standard is, technically, backwards compatible with SDR but most importantly doesn’t require metadata which is a big benefit in the live environment and simplifies broadcast. PQ, then, is next when we hear about the differences in approach from HLG and suggests that this gives better visual peformance than HLG. In the PQ ecosystem, Brian works through the many standards explaining how they differ and we see that the main differences are in in colour space and bit-depth.
The next part of the talk looks at the, now famous, venn diagrams showing which copmanies/products support each variant of HDR. This allows us to visualise and understand the adoption of HDR10 vs HLG for instance, to see how much broadcast TV is in PQ and HLG, to see how the film industry is producing exclusively in PQ and much more. Brian comments and gives context to each of the scenarios as he goes.
Finally a Q&A session talks about displays, end-to-end metadata flow, whether customers can tell the difference, the drive for HDR adoption and a discussion on monitors for grading HDR.
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.