It is an OFX version of the plug-in but it is modified for the use in Vegas Pro.
I kind of figured that out earlier after installing the different demo versions of NV 5.1.4. My summary of being someone with an audio background who is trying to expand my video background knowledge is that like with most things video related I'm finding there are no standards where logic can be followed. Instead you have a supposed standard video plugin OFX format, and Vegas is an OFX host but none of the OFX versions of NV shows up in Vegas but instead you need to purchase the Vegas specific version of NV and it then shows up in Vegas as an OFX plugin. This makes sense to anyone how?
My original thought was that I was thinking I may want to get more into using Adobe AE along with Vegas, and therefore I should purchase the OFX version of NV so that NV would be available for me to use within AE as well as Vegas but instead what I'm learning is that if I would like that scenario, I need to purchase an AE version of NV as well as a Vegas version of NV.
Every time I feel like I'm taking one step forward on expanding my working with video knowledge, it turns into 2 steps backwards. Good grief. 😆
Yes, OFX is a standard with many blackboxes left. It does not necessarily mean one kind of OFX plug-in will work in all host apps which support OFX. Dependend on which particular kind of processing an OFX plug-in needs it may need particular modifications to work in certain host apps (just like some plug-ins need to be fed by more than just one frame at a time) which then may drop the compatibility to other OFX host apps.
As I indicated before, there is no Neat Video (NV) OFX for VP. If one happens to work, great, but I would not chance it. I have various OFX plugins for my 3 video editors and they are specific to the editor, not interchangeable.
Do not compare VST plugins with OFX. They are not the same at all. DAWs pretty much all do the same thing - create and edit audio. VST plugins, including instruments, come with their own interface and they work with most DAWs. They can do this because they do not use the DAW interface in the same way that OFX has to.
With OFX, it does not come with its own interface; it uses the video editor's interface, monitor and built-in tools. If the plugin requires something that cannot be done in the video editor, then it will come as a plugin with its own interface, not as an OFX.
In the case of NV, look at the interface with everything that can be done on the screen itself, including thumbnails of frames before and after the selected frame, etc. You trace rectangles on the screen to identify areas that have the same colour to build a profile (where possible). In a video editor, the second that you move out of the OFX component of sliders and whatnot, the video editor's tools take over. NV may eventually find a way to sort this out, but I expect that it will be difficult to have all of NV's features show up in the OFX area.
Even Mercalli V4 OFX has an Edit button that opens the external editor. NV could have some simple sliders for template effects, but would need the external interface to be able to be fully use the application.
Forget about a version that will work across editors. Get it for one editor and work with that one. With NV, you are best to stabilize, if necessary, apply NV scene by scene, and export to an intermediate format, and use that for editing in a project. Otherwise you are trying to live render NV and it will drag down your editor. Without pre-rendering, you will not get a smooth playback, and when you export, it can take a long, long time if you have a lot of NV treated material.
I don't know what type of material you are using NV for. I use it for videos imported from old VHS cassettes, digitized 8mm and Super8 film, and the occasional video shot in much less than ideal lighting conditions. They all have video noise of one kind or another, and the films have dust that NV can remove. If you don't have video noise, you don't need NV. If you only have a small amount of video noise, there are other tools that do an acceptable job that cost a lot less.
From my recollection, NV started as Virtual Dub Plugin, and I see that it's still available.
Looks like latest NV is up to date with V18.