Ffmpeg mitli pass passlogfile

After a lot of experiments and vmaf/eye measurments we concluded that SD video we do on cpu decoding/encoding (with libx264 library) with 2 passes (cause quality is more better then any gpu SD encoding)
HD we do with cpu decoding and h264_nvenc encoding (we got 3x speeder than on cpu encoding) and we have good quality

I got some idea, when 2 pass gpu encoding is used, then passlog file creates, but it is zero inside, all data is in memory as i get it.
When we use cpu 2 pass encoding, first pass without audio, which gives ~10x speed, if we do first pass on gpu then it gets 20x, but it does not make sense cause passlogfile is zero (so we cannot use it), and second pass on gpu encoding is bad on SD.
Is there any way to make a first pass on gpu and create passlogfile for use it on second pass with cpu encoding?

nvidia forum is dead?

As far as I can tell it is not dead. Just a bit slow on replies from time to time.

NVENC does not create the specific statistics data that ffmpeg needs to save intermediate data to pass log files.

Also you would need NVENC to do “Fake” 2-pass and have it skip the second pass while creating frame stats.

You might be able to implement something yourself by using the Video SDK directly instead of through ffmpeg.

Thanks for reply, i m not a developer, i just thought that it will be helpful for someone except me and for some developer it is about for 1-2 clicks/strings of code to make it happen, or maybe someone could give an advice where and how to add such function

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