Bitrate capped in constant quality mode with NVENC encoders

[BK-Morpheus]

Bitrate capped in constant quality mode with NVENC encoders

[galad87]

AV1 level it's something that can be added. For now you can try to add level=5.1 or the one you want in the advantage options textfield.

Regarding HEVC, the nvenc encoder is probably setting a sane level if you leave it you automatic, because it's hard to know what will be the peak, in this case setting a level manually is the right thing to do.

[BK-Morpheus]

Thanks for the tip with the advanced option parameter for AV1 NVENC.
Indeed, level=5.1 raises the max bitrate to 40Mbit/s, level 6.0 raises the cap to 60Mbit/s, while level=6.1 seems to be capped at 100Mbit/s.

What confuses me is that the NVENC encoder in OBS is able to record (quality based) with way over 160Mb/s while keeping the AV1 encoder at encoder level 5.0

[galad87]

Maybe it's using the high tier, HEVC and AV1 have the concept of "tier", high tier has got an higher limit at the same level.
Try with tier=1

[BK-Morpheus]

Indeed, the tier=1 parameter also increases the bitrate cap, even with only encoder level 5.1.
Thanks for the quick response.

Maybe Handbrake can incorporate the encoder level dropdown menu for AV1 NVENC in the GUI version and also increase the default tier.
With H265 NVENC it would be smart if Handbrake would set the appropriate level when using Auto encoder level to allow for sufficient bitrates.

[galad87]

There is no way to set the appropriate level when using constant quality. It's always a guess. Set it too high, and some hardware players or software players won't handle the bitrate spike, set it too low and some parts will be bit starved. It's always a tradeoff.

[sr55]

Looks like a duplicate of #2873

[galad87]

Yes it's the same, I opened a PR for the AV1 levels: #6020