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Comment by shmerl | Hacker News Reader

Isn't it supposed to have lower bitrate for the same quality? If there wouldn't have been any benefits they wouldn't have developed a whole new codec.

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You want low latency encoding. It doesn't matter if you can half the bitrate of Video but requires 3s delay to encode it. Something which as far as I am concern is done better with VVC.

And that's exactly why OP asked for GPU encoder, those are low-latency and if the resulting stream requires less bandwidth it means that there can be fewer packets on the network, meaning lower absolute re-transmits (the networks relative error rate is the same independent of the data transferred) and faster transmission for slower networks, i.e., in general also lower latency as by-product; latency, available bandwidth and packet amount are often coupled.

Some codecs might be more suitable for encoding video streams which are known ahead of time and utilize similarity of frames both before and ahead to maximize compression (multi pass encoding); they might also require larger buffer. With real time video calls you can't really do that. There is no codec-fits-all solution unfortunately.

Low-latency encoder are not exactly known for producing bit-efficient streams.

Their purpose is to dump the frame into compliant stream in least possible time, so the compliant decoder can decode it back. It doesn't concern itself with using less bits; if it does, it is nice, but not deal breaker.

So if the hardware encoders can produce VP9/HEVC/AV1 at roughly the same bit-budget, it doesn't make sense to use the more complicated one. It makes sense to use the one, where you do have to pay less fees, though.

I don't think bandwidth is the main challenge with video calls. Packet loss and latency cause far more quality issues.

Packet loss and increased latency are the main symptoms of using more bandwidth than the network can reasonably provide.

In live video, latency from encoding is a limiting factor for what types of compression you can use. Its not like bandwidth is the sole limiting factor here.

I don't think you can just dismiss bandwidth concerns, especially when you consider video conferencing.

I can still see compression artifacts, so it's clearly not using enough bandwidth. It could probably compress it better if it had hardware available, rather than needing to do real-time encoding in software (since it doesn't have a VP9 encoder either).

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