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by ksec 19 days ago
Have you said this for Audio Codec I would have agreed. I do not know a single Smartphone Video Conferencing software that uses CPU encoding rather than hardware encoding. Neither WhatsApp or FaceTime, perhaps the largest of the two real time Video Call uses AV1.
2 comments

Yeah, no production or large scale VC system is running software AV1 encoders on smartphones. You will drain a full phone battery in 1-2 hours of calls.

It just doesn’t make sense and will result in extraordinary power/battery drainage at best, or output that’s worse than hardware encoding.

The only way you could get AV1 to software encode in realtime AND low latency on a mid-range Android chip is by disabling or skipping nearly all of the compression/encoding features that make it good at low bitrate.

> Yeah, no production or large scale VC system is running software AV1 encoders on smartphones. You will drain a full phone battery in 1-2 hours of calls.

Yeah but, half jokingly, Zoom does that (draining the battery in an hour) already :P

So, status remains quo, the commons remain tragic, and glory to H.264 forever?
> tragic

H.264 isn't even that bad at all, if not the best depending on how you look at it. Our Internet bandwidth, both on the backend and front end on Mobile 5G is increasing with plenty more room to grow. While computation decoding and storage isn't.

i.e If bandwidth is infinite and free, and we are only optimising for decoding power usage. H.264 wins in a lot of this scenario.

H264 is lacking a lot of features (behind patents) that are essential to real-time communications. It's available, but by far, the worst offender for call quality. Modern call technology will want to use temporal and spatial scaling which are not available in the profiles supported by most H264 encoders and decoders.

Those tools are available for VP8 (temporal only), VP9 and AV1 and improve the quality of calls quite a lot when used right. I don't know about about the internals of H265 and H266 as those are also behind patents and no one wanted to touch them in the real-time conferencing space.

At least until a better codec has widespread enough hardware support, I think.
Google Meet can do it. You don't want the full conference with AV1, just use it for very low bitrate scenarios with a high packet loss possibly. Phones are a good target system. And I know this is quite opposite to expectations.

It is a lot better to send a stable and visually ok stream with AV1 at 30KBps than fail to send a VP8 50KBps stream that is unusable anyway and is subject to twice as many packet lost than a lower bitrate solution.

It is possible they use AV1 in other scenarios now, but I left the team a while back now and I haven't checked what they are now using under the hood.