H.264 High 4:4:4 Lossless - doesn't appear to work with any options through NVenc. Bug?

Hello, Posted in the premiere forum but thought i'd put it here.

Perhaps i don't know the correct settings but i can't seem to get any lossless output from the NVenc using H.264 output in High 4:4:4 lossless profile.

I am trying to upconvert 4:2:2 ALL-I 10bit footage to AVC 4:4:4 10-bit ALL-I footage..

Any thoughts here?

Also, for the NVenc HEVC (h.265) lossless.. its outputting 4:2:0 chroma subsampling? is there no 4:4:4 option for the NVEnc ? I know the NVEnc has the capability of outputting full 4:4:4 10-bit files...

hey thanks for responding..

So far my tests for 4:4:4 have come back with 8-bit results not 10-bit. Also i had errors trying to get 4K footage to output at high enough bitrates. GH5 footage are 400Mbps ALL-I 10-bit 4:2:2 variable frame rate files normally. The NVEnc is capable of 10-bit YUV with ffmpeg and the sdk as of version 9. (https://developer.nvidia.com/FFmpeg). I was hoping since the GH5 footage for H.264 ALL-I 10-bit 4:2:2 that there was an ability of upconverting that footage in that format to Intra 10-bit uncompressed lossless in 10-bit (4:4:4). I know the codec supports it. Since the NVEnc does not hardware accelerate 4:2:2 footage natively, it would be useful to be able to upconvert either to uncompressed 4:4:4 10-bit footage ALL-I for my comparison on the timeline as opposed to using intermediary codecs like ProRes to keep detail and color. I have tried H.265 with some success but the GH5 only outputs 8-bit HEVC footage so not as useful with that codec (yet).

I want to see if the GPU will actually accelerate footage through the entire timeline because the footage is native to the hardware while keeping its detail at 10-bit 4:4:4 Intraframe. I believe its the "H.264 High 4:4:4 Intra Profile  (Hi444PP) 10-bit" is what i'm after for doing this.

If possible this could be a very useful way of avoiding proxy generation while accelerating the footage without having to go to Prores to preserve color and footage detail.

Also what the settings would be to implement this.

I just noticed you have a beta version of 2.1.1 that i just downloaded as well that i'm going to test out to see if this works in that as well.

Thanks.

Again, not sure if this is possible but would like to know for sure within your product and the NVidia RTX 2070 GPU of which i am using for this.

P.S. I Love what you are doing with this addon so far BTW! Performance is a LOT faster for 1080p and regular 4K on the new RTX series cards!