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Old 11th June 2019, 17:17   #1725  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
Posts: 4,750
Quote:
Originally Posted by sneaker_ger View Post
If only Youtube had like .. multiple .. videos coming in daily. Then they could encode them simultaneously on a single CPU each. (And serve AVC or fast setting VP9/AV1 until they are done.)
You could do a fast first pass for scenechange detection and vbv estimation and send the chunks along with that info.
Yeah, something like that would work. It's more overhead, of course, and reduces total throughput. But that's what I'd do if I was trying to get good quality out of what are essentially spot instances.

Quote:
Originally Posted by nevcairiel View Post
This is not something any streaming service does though, so why should they invest into developing stuff for a goal they don't even need?
Its just how it goes. And for UHD Blu-ray discs, they can just throw massive bitrates at it to solve any such issues.
Streaming services for premium content do target really high quality, and most of the time at the top bitrate you won't see visible artifacts.

It's the user-generated content world where you see a visible quality ceiling. The sources aren't as good, and the economics for how many MIPS/pixel and how many Mbps to spend yield more conservative choice.

Also there is a big political motivation to use of non-MPEG codecs by some of the biggest UGC platforms, even when it doesn't make strict economic sense.

Quote:
Originally Posted by vidschlub View Post
AV1 /at scale/ when a video is being watched upwards of 500 times a week, makes so much more sense. Those encode times will eventually pay for themselves.
That's the hope of AV1. At this point H.264 has very mature encoders, so quality @ bitrate @ speed of AV1 and VP9 really don't offer any substantial improvements, and there are quality regressions versus x264 for some content types.

Quote:
Originally Posted by birdie View Post
When I was writing that comment I was thinking about VP9. Aside from YouTube/Netflix you'd consider this codec a failure. The scene doesn't use it. Doom9 users don't really use it. It's become a great codec for content delivery. It's not really used anywhere else.

It's kinda strange we have projects like x264/x265 for patent encumbered H.264/H.265 codecs, yet nothing like that for VP9/AV1.
Yeah, it's a chicken-and-egg thing. Because the market assumes that MPEG codecs are going to be widely used, a lot of people start building commercial codecs while the spec is still being finalized.

Also, the MPEG reference encoders just aren't useful for production due to speed and features. The vp* and AV1 series get a sort of hybrid reference/production encoder. It's "good enough" so people haven't bothered with ground-up new encoders. And specs haven't been close to MPEG quality before AV1.

And we can't discount the unique impact of x264. Legions of video pirates competing on making the best looking files as small as possible as quickly as possible to post to torrent sites meant lots of eyeballs on a very wide range of source content; much more diverse than typical encoder test content libraries. Dozens of people deep diving on tunings instead of a handful. Lots of eyeballs on every new beta to see what's different.

x264 just got good in ways that might be impossible to ever replicate. HEVC is close enough to H.264 that things like CRF and psychovisual tuning worked well enough to refine from. And x264 set a high bar that commercial encoder vendors had to strive to beat.

VP9 never had that kind of interest. AV1 is certainly showing much more competition in commercial encoders already than any vp* codec ever did.
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