Netflix Finds x265 20% More Efficient than VP9

[Baldrick]

Netflix compared 5,000 clips from 500 titles in its library using the x264, x265, and libvpx codecs. x265's implementation of HEVC was the clear winner on quality and efficiency, but whether that matters in light of compatibility and licensing issues isn't so obvious.

http://www.streamingmedia.com/Articles/Editorial/Featured-Articles/Netflix-Finds-x265-...P9-113346.aspx

[racer-x]

Efficiency is one thing, Licensing costs is another. For that reason, I'll predict that VP9 will win out on broadcasting networks.

[KarMa]

Efficiency is one thing, Licensing costs is another. For that reason, I'll predict that VP9 will win out on broadcasting networks.

If they don't already have invested VP9 equipment, then it would just be best to wait for AV1 coming out next year. Which is really just VP10, as Google redirected their unfinished VP10 format into AV1.

[sophisticles]

I admire their patience, they encoded with placebo and single thread for both x264 and x265.

Personally, I see no reason to use a pure software encoder anymore, as MSU proved Intel's Quick Sync is able to beat both x264's and x265's placebo and very slow (respectively) settings and it's many orders of magnitude faster in doing so (has anyone ever tried to encode 1080p with these settings with either codec, it takes forever) and it uses way less power as well.

[-Habanero-]

20% sounds about right, for animated content at least. For all my cartoon samples I got 20-30% efficiency over x264 for medium-to-high bitrates.

[ezcapper]

I think with HEVC being the codec used for UHD Blu-Ray, broadcasters will use it as well for 4k. I would have thought the licensing fees would be waived for broadcasters.

[usually_quiet]

Efficiency is one thing, Licensing costs is another. For that reason, I'll predict that VP9 will win out on broadcasting networks.

VP9 won't last long. AV1 is due to be released next year.

ATSC 3.0 over-the-air TV will use HEVC. The spec is supposed to be completed next year. Other OTA broadcast systems are also already using or experimenting with HEVC. HEVC is relatively mature and hardware decoders are not terribly expensive. At this point I doubt the parties responsible for creating broadcast standards would consider changing to something else, although it might be added later.

Cable TV and commercial satellite services will do whatever they want to. My provider, Comcast, is in the process of switching to H.264 for HD cable-only channels. SD channels and re-broadcast OTA TV channels will remain MPEG-2. UHD on their X1 system is supposed to use HEVC.

[SameSelf]

Netflix compared 5,000 clips from 500 titles in its library using the x264, x265, and libvpx codecs. x265's implementation of HEVC was the clear winner on quality and efficiency, but whether that matters in light of compatibility and licensing issues isn't so obvious.

http://www.streamingmedia.com/Articles/Editorial/Featured-Articles/Netflix-Finds-x265-...P9-113346.aspx

Thanks for this. Interesting. However, I think "clear winner" needs qualification. "Clear winner" if you don't mind the performance hit of placebo (or they don't want to give away their true settings). But as NFLX stated, they take up 35% of peak internet bandwidth, so for them, placebo speeds are a non-issue when encoding once and decoding millions of times. How many times did he say that? I think I counted a dozen. Thus their motivation is a very specific use case, plus I get the feeling they take an OSFA approach to their encode solution. I see bad encodes all the time when streaming, and I don't even go actively looking for artifacts. I am going to go out on a limb and say that Hollywood studios know a thing or two more about encoding for quality.

[_Al_]

I see bad encodes all the time when streaming, and I don't even go actively looking for artifacts. I am going to go out on a limb and say that Hollywood studios know a thing or two more about encoding for quality.

For BD you have more bitrates and you encode parts of video with different settings. They cannot introduce that approach with streaming, so that comparison is not ideal. Watching Netflix, one can see the actors nose hairs during still close up but terrible banding while low light, same gradient, same shadow scene. You might watch actual bitrate distribution watching Netflix on PC I think, there is some key shortcut for that. Or mostly simply they do not have more bitrate available for a scene.

I try to bring it up from time to time, like zones in x264. But all you can hear is - what is the best setting, which does not exist for movie feature for example. Without zones, one just simply must overshoot the quality not getting bad scenes. Video from camcorder, that is a bit different story, differences are usually not that big, here or there, but anyway ...

[KarMa]

I see bad encodes all the time when streaming, and I don't even go actively looking for artifacts. I am going to go out on a limb and say that Hollywood studios know a thing or two more about encoding for quality.

Assuming you have a fast enough connection with your local ISP office, it's not like you get the same speed to every website. Depending on the connections your ISP pays for, they may have a bottleneck with such sites like Youtube or Netflix during prime times of the day. So even though you may have a 100Mbit connection (for example), downloading from Netflix may be limited to a few Mbit due to undersized node connections between your ISP and Netflix. Causing you to stream one of the lower tier encodings.

That being said, why are you even comparing Netflix to Bluray. Netflix uses like 3-6Mbit for their 1080p videos, while Bluray peaks out at 40Mbit and can store 25-50GB for one movie. What do you expect? Are you new to video encoding?

[_Al_]

Also it depends on hardware using Netflix app. Not all devices are "allowed" by Netflix to deliver fullHD for example, not sure how much changed in about a year, read here. Higher resolution means higher bitrate.
For example, allowed Android phones and tablets capable of fullHD streaming are listed here, that is from Netflix website, click on "Netflix in HD" TAB.

[SameSelf]

Are you new to video encoding?

You guys totally missed my point. I am not comparing streaming to bd. Don't put words in my mouth, and don't waste my bandwidth with patronizing descriptions. I was pointing out that nflx's study and their conclusions don't exactly apply to authoring, and I would be much more interested in hearing how Hollywood studios go about encoding their bd's. But I ain't holding my breath. I know those are closely guarded secrets.

But most on this forum know nothing about generating their own content for consumption via web, dvd, or bd. They are too busy ripping and capping. And if that is your schtick, then more power to ya.

[pandy]

My 2 cents:

VP9 is no competition to H.265 due poor specification - Google has no experience in specifying video codecs - this is classic software developers approach...