Interlaced Constant Frame Rate being changed to Variable Frame Rate

The issue occurs in Version
Does NOT occur in Version 4…

Using DV footage at constant frame rate (29.970) all enhancements are coming out with Variable frame rate, a nightmare for NLEs.

I9 12th Gen, 64gb, dual M2 990 pros, RTX 4070 (351.7 KB)

Screenshots are here:

I only received one response from a tech, and he referred to variable BIT rate, which of course is not an issue.

thanks very much,

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BTW: Happens on all these:

I think it has to do with the fact that you are encoding with H264/H265 and using the quality control profile in TVAI.


With NVEnc, the equivalent to CRF is ‘rc=vbr’ with ‘cq’, ‘qmin’ and ‘qmax’ set (I don’t think Topaz uses that approach, shame), which produces an actual Constant Quality / CRF in one pass, but with a variable bit rate, and thus without the downside of wasting disk space like ‘rc=constqp’ (what Topaz is using).

I know, to much technical…don’t bother with it…

Simply try encoding with FFV1 and see if it alters with your Frame rate as well or not. if it doesn’t then, you know it is the hevc_nvenc command and not something else. and that could easily be fixed in the CLI until Topaz will actually change their encoding command…

Hi @Akila,

Thanks for taking the time.

No, I don’t think that is it. I’ve only used ProRes since TVAI added it. In fact I had to look around for the screen of your screenshot. I did find it. (Prefs-Export). I didn’t find it overly technical, I appreciate your note. Perhaps a Topaz person can confirm they are aware/looking into it.

I just did an export using FFV1, and had the same results.

There’s no problem with VBR, it’s a good thing. But VFR is a very bad thing. Hopefully it’s an oversight, but the only Topaz tech who responded was only talking about VBR, which was not part of the issue.

Thanks again.

with FFV1 I am getting constant fps. with H265 I am getting variable fps.

Are you using a mkv container when getting CFR ?
If so export using mov container and see what happens.

Yes, I just tried with an .mkv extension, and indeed that comes out as CFR. Apparently the .avi comes out with CFR.

None of those will go into Premiere Pro, giving an ‘Unsupported format’ message.

Hi @gpasquini this should be resolved in the 5.0.2 update that just went live.

Thanks Tony.

I’ve been waiting for the beta link, but finally realized it was an actual release. I’ve only just been running the beta’s.

This was nearly a show stopper, but I’ll call it fixed now! :-).

Thanks again.

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