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Comment by WhitneyLand | Hacker News Reader

And yet phones are already doing real-time 4k video encoding.

In other words, since a lot of compute intensive scenarios are already being served by less general purpose hardware, what are the most recognizable scenarios where AVX-512 will make a big difference over AVX-256?

I know video encoding can be an integer only algorithm while AVX seems to help floats more but still...

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Which phone can do realtime 4k encoding? Can you tell me which SoC it uses?

Edit: It's the Acer Liquid S2, with Qualcomm Snapdragon 800 SoC

All Snapdragon 800-based phones, and there are quite a few of them, and there will be more in the coming months (and of course later even more chips doing the same). Right now it's the one you said, LG G2, Sony Xperia Z1, Samsung Galaxy Note 3, and soon the Nexus 5.

Now I'm not 100 percent sure if every single one of them has that as a user-centric feature (maybe they didn't enable it), but the chip supports 4k video recording.

Surely you'd prefer to encode video much faster than real time.

If it can do it instantly, that would be great. But why does it need to be faster than real-time? You can't capture video any faster. (Though, "real-time" probably needs some sort of framerate qualifier… no doubt 60 fps is harder to encode than 30 fps.)

Unless you're thinking of re-encoding … on a phone?

Sure, that way you could apply shake-reduction or framerate adjustments (like slow motion) after capture. Or, re-encode to send as MMS or something.

Yeah, there's always more processing on a video that can be done. Shake/Jitter reduction, histogram normalisation, hipster-like (instagram) filters, etc. (Just imagine a real time instagram filter for video on your phone.)

Edit: Plus it means less power used since the processor doesn't need to be on for as long to process the video (duty throttle / pulse width modulation etc).

I think AVX is for scientific computing where there are a variety of algorithms that can't justify specific offloads like video encoding.

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