ShotANVIL: Enhancing AI Generated Masks (Tutorial)

Hi. So I would recommend you watch the tutorial on ShotANVIL Basic Concepts before this one. And this is going to explain to you how to add and subtract from the keys that are generated automatically by the various, uh, templates we have, which either have AI mask person on the end, or, uh, there's Grade Person and Key Person.

So in this case we're using Key Person on the clip and you can see what that does automatically. Um, and obviously it's not gonna get it right a lot of cases. And you're gonna want to use either paint strokes, track paint, strokes, or tracked masks to improve the result. Okay? So we open the editor and key person here is generating the mask internally to the layer.

So you can't directly edit it, but I'll show you the of various ways we can, we cannot modify it and the source layer is switched off because of this case. We want to key over nothing.

So you could put it over another clip, uh, of a timeline. Uh, you turn that back on if you want to, but for now we'll leave that off. Okay? And so first of all, the, the basics for built-in controls.

You've got three quality levels for the, uh, estimation of what's a person and what's not. You can of course invert it and blur the edge and then expand or shrink the mask, which work as you'd expect, that's expanding it, and this a shrinking it, okay?

But we wanna do obviously more than that, uh, although we probably would wanna shrink it about that much to get rid of some of the fringing on the edge in this case. So let's leave, leave it like that.

And there's multiple ways you could do this. As with everything in ShotANVIL, lots of different ways to do it. So first of all, let's say you wanted to fix edges with um, painting frame by frame. So we'll show you that first. Okay?

So in a case of frame by frame painting, we can do it in the same layer as the generated key. And what you need to do is click here. This button changes from a stroke, which lasts the entire clip to a stroke that's only on one frame.

And then if you want to add to the mask, you use this one here, which is called the reveal source brush because what it's doing, doing is painting the background back over. So I can go like that and that's adding more of a background and then if I went to the next frame, it disappears, but I could just paint again and so on to fix an issue with a mask that way. Obviously not the best way,

but that's possible. Okay, let's just delete those. Hold shift minus button there. If we wanted to subtract from a mask, you use this one here called the mask brush, but make sure you change the mask mode to subtract.

And then the same I can cut away from a mask. Next frame, next frame. So on lot. So that would work. You could do as many strokes as you want if you need to do frame by frame touchups either to add or subtract.

But now let's move on to doing it with tracked brush strokes and or tracked shapes. Okay? Again, delete these hold shift. Now in this case I'm going to make a new layer before I add a track because every layer could only have one track as we set in the basics tutorial. Okay? So first of all, remember to turn off the single frame mode that's puts it back to the default where every brush stroke lasts the entire clip.

Now I want to go here to add a new layer and I want to change for layer to minimum. And we'll name this to subtract mask. And then we've gotta do one thing. We've gotta add in here a mask to alpha and then draw a shape and set that shape to subtract. Okay?

So the reason we did the mask to alpha is because we want this shape to not only affect what's in the layer, we want it to actually cut out the um, alphabet's generated for all the layers.

So that's why we need the mask to alpha. Now that mask can now be tracked. I can just go ahead and Check The settings, hit the track button and, and it will follow. Now that's the same as we've seen in size X and the other plugins. If you wanted to instead, uh, subtract using subtract brush stroke, then again we would use the same technique we used before.

Use this one here, which is for mask brush. Make sure it's set to subtract, draw a stroke and then hit the track button. And that is subtracting from a mask. Now if it's not working, make sure that you have the mask to alpha on the top.

So you can put shapes, multiple shapes and brush strokes below this, right? So I could again go here and eat away of air and then track again. That will all work fine as long as master alpha is for top thing in the layer.

Okay? So turn that off and now show you how to add to the mask. Okay, let's go ahead and add a new layer. Call this add to mask. And again, I can do this either with a brush stroke or the shape.

We'll use this one here that we used before called reveal source brush. And when I paint to anywhere, what this is doing is expanding the mask to show more of the original source clip. So if I had eaten into the hair too much, I would use this to expand it back out again. Okay, so turn that off. Uh, sorry, before quickly just show you that that can be tracked the same as normal.

Just go ahead, hit the track, track motion button. Okay, let's stop that. Go back to the start and turn that off. And now to add a shape, it's a little bit more complicated because uh, we've already kind of erased the, uh, the outside. And to bring it back with a mask, you need to add a source clip like this and then apply a mask with a default settings for mask mode, et cetera.

Now that's bringing back, or it's expanding the mask to show more of a background. And the only thing is this polygon shape, I need to make sure that it's not a child of a source clip, right?

It needs to be here, right? So it's on the same level as the source clip, not a child of a source clip. And then I could just hit the track forward button And it works as you'd expect, adding to the, to the mask that we've created. We've a key person.

Now you can combine both shapes and masks in the same track layer. So I can turn this back on the only figures that any, if you want to use reveal source brush and make brush strokes to add to the mask, they need to be at the bottom. The reason is because the polygon shape is applying (*masking) everything above it.

So if I put this up here, it doesn't do anything 'cause it's not inside the mask. So again, hwne building masks, they work in order from bottom to the top. And so because this is below the shape, it's not being limited by the shape.

Um, again, you can use the eye icon here to see that because you can look at the mask for each layer and we can see that the mask here is only that shape.

So anything that's outside that shape that's above that won't be seen. But anyway, let's go back to looking at the result and just summarize what we've done. So to subtract the mask, we could do, have done it a couple of different ways.

We could have painted stroke by stroke using this one here or with these layers. Here I showed you how to use the, uh, mask brush set to subtract or to use a shape set to, uh, subtract as long as the layer here is set to minimum.

And then to summarize how to add to the mask, we just added a default layer, left it, the default settings, added a source clip, and then a polygon shape again of the default layers.

And that will add back to the mask as long as I'm looking up here or turn that off. And then if you want to, um, add to the mask with a brush stroke, you make sure it's at the bottom and use reveal source brush. Okay?

If you've got questions, let us know.