Video: A Technical Overview of AV1

If there’s any talk that cuts through the AV1 hype, it must be this one. The talk from the @Scale conference starts by re-introducing AV1 and AoM but then moves quickly on to encoding techniques and the toolsets now available in AV1.

Starting by looking at the evolution from VP9 to AV1, Google engineer Yue Chen looks at:

  • Extended Reference Frames
  • Motion Vector Prediction
  • Dynamic Motion Vector Referencing
  • Overlapped Block Motion Compensation
  • Masked Compound Prediction
  • Warped Motion Compensation
  • Transform (TX) Coding, Kernels & Block Partitioning
  • Entropy Coding
  • AV1 Symbol Coding
  • Level-map TX Coefficient Coding
  • Restoration and Post-Processing
  • Constrained Dire. Enhancement Filtering
  • In-loop restoration & super resolution
  • Film Grain Synthesis

The talk finishes by looking at Compression Efficiency of AV1 against both HEVC (x.265) & VP9 (libvpx) then coding complexity in terms of speed plus what’s next on the roadmap!

Watch now!

Speaker

Yue Chen Yue Chen
Senior AV1 Engineer,
Google

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

Video: Get Ready For A Multiple Codec World

The codec world is fragmenting. None of the new entrants on to the market is expected to ever gain the universal status that AVC enjoys. This panel from Streaming Media East takes a look at how to prepare for this.

The panel kicks off discussing the differences between AVC and HEVC, VP9 and AV1 and moves on to discuss the pros and cons of supporting multiple codecs. Tarek from Twitch explains its partial adoption of VP9 – the reasons that it makes sense but the overheads which it brings the business.

Vittorio Giovara from Vimeo explains their reasons for using HEVC including their drive to be able to encode and deliver 10-bit video. Ellation’s Subhrendu Sarakar makes the point that managing codec changes and bitrate changes needs to be done carefully to ensure viewers that notice the change understand them and don’t feel there has been a reduction of quality.

After a brief discussion of encoding strongly characterised video types such as anime and gaming, the conversation moves on to AV1 and migrating from VP9 and there is an audience question on HEVC licensing and the lack of use of SVC (Scalable Video Coding)

It’s now relatively well known that Twitch deployed VP9 using FPGAs rather than as a software encoder which was the only way to get the real-time speed at 1080p60. The panel discusses encoding speed both in the encoder and decoder for VP9 and AV1 then finishes with a Q&A from the audience.

Watch now!

Speakers

Tim Siglin Tim Siglin
Founding Executive Director
Help Me! Stream
Tarek Amara Tarek Amara
Principal Video Specialist,
Twitch
Vittorio Giovara Vittorio Giovara
Senior Engineer, Video Encoding
Vimeo
Nathan Egge Nathan Egge
Video Codec Engineer,
Mozilla
Subhrendu Sarkar Subhrendu Sarkar
Senior Engineering Manager, Video Infrastructure & CMS,
Ellation

Video: Analysis of emerging video codecs: coding tools, compression efficiency and complexity


Delivering great quality, live video without breaking the bank is difficult. This talk looks at the different ways companies are dealing with this challenge.

NGCodec’s founder, Oliver Gunasekara, starts by quantifying the millions of dollars spent just by one company each year just on delivering their video and introduces the difficulties of CPU encoding compared to dedicated chips – ASICS and looks at how FPGAs fit in. Cloud-based FPGAs are available on AWS, Baidu, Alibaba and others.

After covering Twitch’s move to VP9 on FPGA, the talk finishes looking at on-premise implementation, Oliver looks at the cost of ownership of servers compared to Xilinx FPGA.

Speakers

Oliver Gunasekara Oliver Gunasekara
Founder. & CEO,
NGCodec