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Comment by ksec | Hacker News Reader

I am more looking forward to future release. The current version is mostly a bitstream freeze. And it is anywhere from few hundred to few thousands times slower at encoding. While the current version isn't optimized at all, I wonder how long would it take them to reach, say within 5x the speed of x265.

In another news, we have xvc, which is taking most of the H.266 purposed ideas into its implementation. And it is already showing 30% better compression then AV1.

Note: AOMedia have also updated its website.[1] One thing i notice is Apple is the only one not using its Logo in the member site. And this feels a little strange.

[1]https://aomedia.org/membership/members/

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> I am more looking forward to future release. The current version is mostly a bitstream freeze.

It's not even a bitstream freeze. This 'release' was put out by the marking folks, and wasn't even discussed with people on the AOM list (I'm part of AOM via VideoLAN). The bitstream remains under development.

Near as I can tell this is just a PR piece before NAB.

Oh Christ. I thought they were fast, only last week they said they have a few bugs still left to be fixed. ( And only last month they said they were still listening to hardware makers on suggestions and changes to improve decoding speed )

Thanks for pointing this out.

One reason why I dont like / trust the folks at On2 / VP8, it is nice AOMedia now has folks like you to keep them honest and humble.

Have a nice day.

There is concerted effort on the AOM list to finish and close all bugs or features that require normative bitstream changes, so I would expect it isn't too much longer. The number of remaining issues is small-ish, but not zero.

The involvement of hardware people has been a boon, though tough for software people at times :).

Oh no :( I monitor the AV1 bugs, and repos and was indeed puzzled to see this. So it hasn't actually been released. OMG, this is really bad and could backfire.

Even following the things above, it can be pretty hard to see what's going on.

EDIT: mailing list is not accessibly, had some bits flipped in my wetware

I check bugs and repos often, but I don't know about the mailing list, where is it located?

The AOM engineering list and kavi tracker is restricted to members of organizations in AOM, as far as I am aware.

Oops, I mixed up TLS and AV1. Right, mailing list is off limits to me.

I figured everyone understood this, but you are right, it bears spelling out:

Any modern [video] compression format is extremely flexible and allow great liberty for the compressor (whereas the decompressor is strictly defined). This means that there is ample room for work on improving the quality and efficiency of the compressor for years to come.

In other words, AV1, the spec, isn't some magical unicorn. It's the sandbox in which the 'corns can be raised.

Compressing a video looks like a huge decision tree to me, and newer standards add more interdependencies and more variables at each stage. I'd expect that the resulting optimization problems approximated by encoders are computationally difficult. (Which would explain why they always get better even after many years)

Short answer: yes Long answer: yes

My personal analogy for this is that video encoding standards are basically like toolkits for building houses, while encoding software is like a robot trained to build those houses using the tools in question. New standards bring new tools to the toolkit, but training the robots to use them effectively is going to take its time and is often even worse than the previous robots in the beginning simply because the older robots have gotten so proficient with their respective toolkits. x264 in particular is basically the top robot in this department and the standard which any new entrants should aim to beat both in quality (not necessarily too hard) and in time efficiency (which is the much bigger challenge).

I don't think time efficiency is the primary concern for the big encoders like Netflix and YouTube. They're more interested in lowering the bitrate while maintaining image quality and are willing to throw compute resources at slower encoders which achieve that. Netflix, for example, does multiple encodes per scene in multiple formats to get the best possible quality for each format for each scene.

VP9 outperforms H.264 (libvpx versus x264) for Netflix's use case. Here are some articles from the Netflix TechBlog on their experiences with VP9 and their encoding approach in general:

https://medium.com/netflix-techblog/optimized-shot-based-enc...

https://medium.com/netflix-techblog/more-efficient-mobile-en...

https://medium.com/netflix-techblog/netflix-downloads-on-and...

You're right, time efficiency certainly isn't as big of a concern for companies with effectively infinite resources to throw at encoding, but the rest of us probably want to finish our encodes within this decade :) (the reference AV1 encoder is extremely slow)

Time efficiency is still important for live streaming. Last time I checked (OK that was one year ago) x265 was way too slow for live, even at not so high resolution.

Bitmovin produced an AV1 live stream a year ago using 200 cores: https://bitmovin.com/bitmovin-supports-av1-encoding-vod-live...

And six months ago they had improved on that to do live streaming with 32 cores: https://bitmovin.com/constantly-evolving-video-landscape-dis...

So I'll be interested to read about any live streaming demos they do at NAB in the next couple of weeks.

It's impressive that AV1 allows so much parallelism. That's great news.

It is a concern even for Netflix. The number only starts to make sense assuming a 30% bitrate reduction and 5x speed encoding time. This means the current encoder needs to speed up anywhere from 50x to 500x to get to that point.

Imagine if Netflix spends 1M on encoding, even 5x is 4M more, and the current encoder is anywhere from 250M to 2.5B more. This is not a small sum of money.

I think before they talk about speed up, they just need to iron out all the bugs and bitstream freeze before we speak.

Netflix have said they'll roll it out once it's below 5x slower.

But they can start with only the most popular videos to get the most bang per buck, they'll also likely target geographic areas with low bandwidth but decent spec desktops, which means they're getting a return on investment by increasing reach, not just saving bandwidth.

So basically, there's plenty of niches where it makes sense almost as soon as the spec is frozen and they can expand the roll out as it proves itself and speeds up.

Potentially unrelated but having run events with Apple as a sponsor in the past, they are especially stringent on how/if they allow you to use their logo or branding. We were also forced to go this route.

I'm trying to make sense of the xvc licensing. Is it some sort of weird licensing joke?

It is if you think about it from a patents and licensing perspective. However I will try to take another spin to it which might be something they are trying to do without actually saying it.

They implement all the H.266 JVET ideas and tools into xvc. Not every one will make it into the standard due to speed, politics or whatever. Once the H.266 has been standardise, they now have a decent working encoder they could turn on the the features are in JVET and be the first JVET encoder on the market.

The JVET working group knows there is a threat in Royalty free codec like AV1. So I am hoping they take the patents and cost into account. But given how Qualcomm, Ericsson, Sharp has been acting in HEVC i am not entirely sure it will be smooth. Or if JVET has a future at all.

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