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Old 30th May 2019, 22:20   #1697  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by nevcairiel View Post
Encoders are no longer being made for this crowd. The primary design goal is massive-scale cloud encoding for YouTube, Netflix, Amazon, and everyone else that fits the encode-once, download hundreds of thousands of times scenario.

In such a scenario, even the slowest encoder is acceptable if it saves enough bytes.
Oh, these things are always down to cost benefit. Google is just willing to subsidize VPx/AV1 to a huge degree, and likely has a lot of spot-idle capacity in data centers to do the encoding.

But high quality encoding doesn't work with chunks of a few seconds. Encoding longer sequences allows for IDRs and shot changes and more aggressive VBV use. YouTube can have quite a bit of keyframe strobing with difficult content for these reasons. YouTube quality wouldn't be acceptable for lots of premium content.

There has never been a VP9 encoder that offers sufficient quality OR performance for premium content, and there isn' one for AV1 yet either. I don't think this is because the VP9 bitstream wasn't capable of it, it's just that no one wrote an encoder with good psychovisual tuning, intra-frame parallelism, and other stuff.

Encoders are a real chicken-egg problem. There needs to be enough companies willing to pay for better encoders to create a competitive market so that companies work hard to make better encoders than each other. That market never emerged for VP9, so libvpx never saw the kind of quality and performance improvement of, say, the H.264 or HEVC reference encoders to the best available commercial encoders.

There is clearly more interest in AV1 than there ever was for VP9, and more quality innovation already than VP9 has had to date. Which is very promising.

Quote:
In that scenario, VP9 also didn't fail. It gets used for a lot of content on the web.
Other than YouTube?

VP9/s niche is user-generated non-DRM social media content. And in practice, H.264 would have offered at least equivalent quality at equal encoding time due to faster and more psychovisually tuned encoders. An x264 running at veryslow speed is going to be the same speed as a quite low-complexity VP9 encoder, especially on high-core systems. The quality comparison for high volume use are done at quality @ bitrate @ time.
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