Media Size handled diff if "Legacy AVC Decoder" isn't used! RE: Neat

RedRob-CandlelightProdctns wrote on 5/14/2025, 8:28 PM

REF: I believe this is related to a prior thread, but is a different topic:

https://www.vegascreativesoftware.info/us/forum/what-frame-size-is-handed-to-neat-video-project-or-actual-media-res--145055/

Project Setup/Background:

Vegas Version: Latest V22 build
Project is 1080p60
Media: Most media is 1080p60. My wide cam is 4Kp30
Render Format: Magix AVC 1080p59.94
Setting we'll be discussing: File I/O "Use Legacy AVC Decoder"
Add-in discussed: Neat Video v6.5

Observed Problem:

NEAT is applied to some of the 4K wide events, to the LEFT of Pan/Crop. I'm using a saved profile that was sampled while using a project that was set to 4K on that same camera media.

During playback, sometimes the preview window shrinks the image to 1/4 of the preview display, top-left corner, then it jumps back to properly fill the preview.
When rendering, that 4K wide event is rendering filling only the top-left 1/4 of the output (2nd image above)

Troubleshooting and Finding!!

I changed various Vegas and Neat settings to reproduce and eliminate this problem. In the process, I found something very interesting that may reveal an underlying problem with the newer Vegas Decoder... read on!

The following made no difference (same results)
1. Changing Render profile (using AMD or not)
2. Changing the selected Hardware Decoder (RX470 or Intel 630)
3. Changing Neat Video to only use CPU vs CPU+GPU
The following resulted in correct render:
1. Disabling Neat Video on that event
2. --> Enabling Legacy AVC Decoding

Enabling Legacy AVC Decoding fixed this problem.

I then noticed something else that I believe is related to the thread mentioned at the top. I think this is significant.

When Legacy AVC Decoding is checked -- Looking at the "General" info in Neat, it properly shows the event is 4K
When Legacy AVC Decoding is UNchecked -- Looking at the "General" info in Neat, it incorrectly shows the event at 1080p

It seems something about the new decoder is incorrectly handling the 4K event as it passes it (or info about it) to Neat Video.

I suspect this is the root cause of the problem here.

Thoughts?

Back to post

Comments

RedRob-CandlelightProdctns wrote on 5/15/2025, 10:23 AM

Have you sent message to them or posted in forum? I cannot find your message in their forum (wanted to add my comment there and confirm the issue on different system).

Via support email

RedRob-CandlelightProdctns wrote on 5/28/2025, 12:27 PM

Update: I heard from Vlad at Neat that they were able to reproduce the problem using a different tool (not Neat) and it appears Vegas isn't passing accurate/correct frame information for frames surrounding the current frame to 3rd party tools. They're reportedly working with the Vegas team to get this fixed up. I have no further info but am happy to hear of progress getting it resolved! :-) :-)

bitman wrote on 5/29/2025, 4:48 AM

@RedRob-CandlelightProdctns Thanks for the update! I am monitoring this post, as I was about to purchase a license for NEAT. This issue is holding me back however. I have good experience with denoising using AI based Boris FX ML denoiser. It is extremely simple to use and gives excellent results, the drawback is there is not much you can configure and it is also extremely slow. Neat in demo on the same clip is about 2x faster timeline play on my system.

I do set pretty most of all my FX (including Denoise) after pan/crop. I know this will work on the reduced data (project set to full HD and source 4K), and as such uses less pixels to work with, but for my use I think this is the preferred way: I tend to film handheld wildlife, so I crop in post to zoom 2x (so I can have 1200 mm in 35 mm equivalent and no HD quality loss if I use 4K source) and do some stabilization (which requires a crop anyway to get rid of black bars and corners) + I usually need to boost shadows by FX's which increases noise, so denoise is usually towards the end of the FX chain, with the FX chain after the pan/crop.

Putting your FX's after the pan/crop (when project has a lower resolution than the source) also speeds up timeline play and rendering as less pixels need to be treated by the various FX's.

bitman wrote on 5/29/2025, 5:01 AM

@RedRob-CandlelightProdctns I forgot to ask: does the issue with neat (and apparently with other applications), also is a problem when placing neat after pan/crop?

I wonder if providing incorrect information to third party applications about the frames surrounding the current frame could be negated (implicitly solved) by the pan/crop conversion itself if the third party application is placed after the pan/crop.

bitman wrote on 5/29/2025, 5:05 AM

I can think of other third party applications such as Mercalli V6 OFX plugin for stabilization, probably also uses surrounding frames...

Andreas-T wrote on 5/29/2025, 9:11 AM

@bitman

Placing Neat video after pan/crop has no problem.

Placing Neat video before pan/crop but zoom with pan/crop just a few pixels also has no problem.

Mercalli v6 has no problem before or after.

Twixtor has a similar problem with Neat but also is solved by zooming in pan/crop.

bitman wrote on 5/29/2025, 12:27 PM

@Andreas-T Thanks for the clarification!

Dexcon wrote on 5/30/2025, 7:44 AM

In a long-form project (e.g 1.5 hours +), some FX including Neat NR if applied to a lot of video events can really slow down the render time of the project, so what I've done for a long time is to create another project solely to apply FX such as Neat NR (as well as some BCC FX involving Mocha tracking) to the original video event with no pan/crop or other FX involved and render the individual events to an UHD .mp4 or .mov (ProRes) media to replace those particular events in the main project. Pan/crop adjustments and other FX can then be made in the main project on that rendered media.

fifonik wrote on 5/31/2025, 4:30 AM

In a long-form project (e.g 1.5 hours +), some FX including Neat NR if applied to a lot of video events can really slow down the render time of the project,

FYI: NeatVideo has cool feature that allow you to turn off its processing in all fragments for a session.
You can turn it on in the session if required or it will turn on automatically if you close/open VP.