Profile Main10 doesn't work right after driver 555.85

[intellq]

With driver 555.85, the following command line:

nvencc64 -i movie.mkv -c hevc --profile main10 --vbr 20000 -o video.hevc

Creates a file with wrong bitrate (and size). The resulting file would be with ~5000 kbps, instead of 20000.

Reverting back to 554.42 (or any older driver) results in a file being created with the right size/bitrate.

Tested nvencc 7.53 and 7.51, same behavior.

[rigaya]

I suppose something weird going on with the new driver, as I also can reproduce the issue by just updating the driver.

At this time. I can only suggest a workaround, please have a try adding --qp-min 1.

[intellq]

Thanks for the quick reply.

--qp-min 1 seems to fix the issue.

Can you explain what it does, instead of the "unset" default?

[rigaya]

Nice to hear the workaround works. I’ll make that default in the next release.

qs-min simply sets minimum value of the qp. qp-min 1 should be same as unset (no limit), but somehow it seems like that the new driver is doing something weird when unset.

[rigaya]

NVEnc will apply "--qp-min 0" by default, so will have no problem with 555.85 driver.

(Previously I suggested to apply --qp-min 1, but after further testing --qp-min 0 also seems ok, so I've made --qp-min 0 default)

Thank you for your report, I'll close this issue as the problem was solved.

[k4oma]

--qp-min 0 and qp-min 1 do not work with [Forced 3 strip split frame encoding set.] CBR bitrate of 3500kbps becomes excessive during hardware encoding. < 18000kbps.