All language subtitles for 08. Four Point Tracking

In this lesson, we're going to learn how to do a four point track.

OK, so we're right here where we left off in our last lesson.

We've gone ahead and stabilized our image.

Now, you don't have to pick up from exactly where I left off in the last lesson.

You could just start with your 08 underscore begin to follow along here.

So I'm going to go ahead and clear my Properties bin.

And then we'll just get started adding some new Nodes.

So the tracker we used before was only used to stabilize the image.

So we're actually going to need a second tracker to get

the four points of our screen tracked.

So let's go ahead and add that in.

It's going to be after the Transform Node though because we want it

to have the nice stabilized footage to look at so that it doesn't

have as much possibility for error.

So we'll go ahead and leave that Transform Node selected here.

Just make sure that's highlighted.

Then we'll come up here just over here to the empty area in your Node graph.

Hit Tab.

And type in Tracker.

And you select that.

And hit Enter.

It's going to drop in your Tracker 2 underneath your Transform Node.

And now we're going to go ahead and zoom in on this screen.

So the way I like to apply my trackers is by doing them one a time.

Now you're going to have four trackers.

So you might just want to click this Add Track four times.

But I think it's a little bit easier to do it one at a time.

So the way that these trackers need to be added is important

because of the four corners of the screen.

So once we start hooking the data up later to the transformation,

it's going to be important that this is in a certain order.

So the way I remember it is I start with my first tracker,

and I put it in the lower left hand corner.

Now it's lower left hand based on how your image is oriented.

So because she's looking at the phone this way,

I'm kind of looking at this as it's lower left to her,

lower right, upper right, upper left.

And you just go counterclockwise from there.

So your track one is going to go in the lower left.

We'll zoom in here.

The lower right we'll have as our Track 2.

Move up here to Track 3.

Add a track.

Put that in the upper right.

And add one last track, Track 4 for the upper left.

So it's not-- you definitely want your trackers in order as far as one,

two, three, four if you're going around the square like this.

If you do put them in a different order though,

you just have to be careful when you're hooking them up to the corner

pin node that we used to apply the data later on.

So now what we need to do is let's start with track 1 and kind of just

figure out exactly how big this pattern area needs to be.

So in the very first lesson-- or excuse me,

in lesson two, we were talking about what to look out for when you're tracking.

And one of things was to watch out for areas in shadow.

But one of the problems we have is that our corner is in a shadow.

Her finger's casting a shadow on it.

So we don't really have much choice.

The good news is we still have quite a good bit of contrast between that

white phone and the black background of the phone.

So that's going to help a little bit.

So I'm just going to make this a little bit smaller so

there's a smaller pattern area there.

And then let's just continue doing this for our other tracks.

So obviously, that pattern area is way too big.

We'll make this a little bit smaller.

And you can make the search area a little bit smaller as well.

We'll do this for all three of these simply because it's

going to help the tracks go faster.

And it's also going to help them be more accurate to have less of

a large kind of confusing area to deal with.

Now I think that probably the one that's going to have

the most trouble right off the bat, I can already tell you,

is going to be Track 1.

But we'll just kind of track through the rest of this and just see what happens.

So I'm going to go ahead, and we'll come up here.

Select all four of your trackers.

Now that's important.

You want to make sure that they've all been selected,

that they're all highlighted in orange.

And honestly,

it doesn't matter if you check any more of these

options here for the translation, rotation,

and scale because all of the data is still going to be captured here.

And the way that we apply it it's not very necessary

for it to have any of those checked.

So you can just stick with the default on that one.

So again, it looks like we set our trackers up on 19,

which we probably should have started at zero.

No big deal.

We'll just track forward and then track backward from that point.

So go ahead.

And let's just hit track to end and just see what happens.

So the most part, these look pretty good.

I'm sure we'll have to get back in here and do some adjusting.

But let's just get a rough track kind of finished up just for this first part.

I'm going to go ahead and pause this so you don't have

to watch this calculating through.

And we'll come back when that's finished.

OK, so our tracker finished up.

Now let's go ahead and just select these tracks one my one.

And we'll watch them through.

And I'm actually going to start with Track 4 because I think

that probably had the highest success rate.

And I want to hear some good news.

So let's go ahead and just kind of scrub backwards.

What I'm doing is I'm watching this area here to make sure that

stays in basically the same place on the phone.

It looks a little jumpy but not terrible.

Now right about here we get a huge change in our brightness

because we get a large reflection on our phone.

And it really moves a little more that I'm comfortable with.

So I'm going to move this back to right in here about frame 170.

And with only Track 4 selected, I'm going to delete everything before that.

Now we may have had some good data.

But it's about half and half.

And because we're scrubbing backwards, I'm just going to do it that way.

So we'll clear backwards.

And let's just go ahead and even maybe move this up a little bit closer.

And then we'll start just by hand tracking previous.

And there it starts to kind of get off kilter a

little bit because it's much lighter.

So we'll just move that back into place.

And you may have to do this for a few frames until it

gets used to that change in the color.

And now it looks like it's getting a little too close to the edge.

So we can pull that back down maybe a little far to the right.

And you just do a few until you get several in a row that look very consistent.

So now it's starting to look very consistent again.

I'm just going to hit the automatic Track to Start.

And that looks pretty good.

Now it looks like we may have gotten a little bit of a hiccup in there.

But we can go back and check that in a moment.

And we're just going to let that finish up.

That looked pretty good there.

OK so let's just kind of scrub backwards.

Got a little bit of a hiccup in that area, not terrible.

Just continuing to scrub backwards there.

And right there, we get a pretty good little kind of jump.

It's not the worst.

But I think this one could probably be moved down a little bit.

So let's just go ahead and do that.

We might not have to do it where we delete anything.

So I think that's probably close enough.

Let's go ahead and move this one down as well.

And it looks like we have quite a few in this area.

I don't want to have to delete too much because it looked so good at the end.

But we may have to.

Let's just go ahead and delete everything backwards of this point.

So Clear Backwards.

We'll move that tracker down and just do a few tracks,

just a few Track Previous.

And that can happen for a lot of reasons,

changes in brightness,

the pixels kind of shifting in color because of that brightness change.

And now this is looking very consistent.

So let's just go ahead and Track Backwards to the start.

That looks great.

Really, really consistent.

Perfect.

OK so now we're pretty happy with the way Track 1 looks.

For the most part, it's really staying in place.

And this is very, very zoomed in.

If you come out here to almost that full size,

that's almost going to look perfect.

So we're being very meticulous here.

Now Track 3 and Track 2 I know are going to be very similar.

So I'm going to challenge you to take care of those in between lessons.

Just double check them the same way we did Track 4.

But I'm going to help you with Track 1 because I

know that it's going to be tough.

So we're going to skip over to Track 1.

And we'll start on frame 297.

And let's just watch this as we go here.

So we're just kind of trying to stay in that corner.

And already you can see it's kind of bouncing around a little bit here.

So we probably need to redo lot of this data.

So I'm going to come over here to 297.

We'll just start there.

And honestly,

I think that this could actually be a little bit closer in the corner.

So you know what I'm going to do?

I'm just going to delete all the previous data.

And we'll move that tracker up into the corner a little bit better.

Since we're starting so early on, we might as well.

Now let's just Track Backwards a few.

And it looks like it starts to get off there.

So we'll pull that back.

And you don't have to be as meticulous every time as I'm being here.

But whenever you have a screen replacement like this,

it's very easy for it to become really distorted looking by

just having a few pixels wrong in your track.

So I would definitely say that this is where you want to spend

the most time on getting your track perfect,

even if it means doing it by hand.

And you can see that I'm still moving through it at a pretty decent pace.

It's not like it's taking me all day.

And honestly,

sometimes doing it just by hand like this is faster than letting the

whole thing track through to the end and then realizing that it

really wasn't as good as you thought it was.

And you have to start it over and delete frames.

Sometimes it's a good tool.

It's definitely going to work for you to do that for

Track 2 and 3 and between your lessons.

But for this one, it's tough.

Now another thing that you can do to kind of help boost this is

to change one of the options in your tracker.

So what I'm going to do is come over here to my settings.

So just go ahead and click that Settings tab.

And then you're going to just take a look down here at this box

where it says Adjust For Luminous Changes.

It tells you right here when you hover over it.

If your footage changes brightness suddenly,

then it's going to help to do some filtering to compensate for those changes,

which is exactly the problem we're having here.

It's getting brighter whenever those reflections happen on the screen.

So by checking that and going back over here to our tracker,

we might be able to track automatically a little bit more effectively now.

So let's go ahead and just try tracking to start with that option pushed.

And it looks like it's sticking to that corner, honestly, much better.

Now it's dancing around a little bit.

But it's not terrible.

So that option definitely looks like it helped a little bit.

Now you don't want to check that unless you absolutely must.

And here it looks like it's pretty far down from the corner.

So I'm going to go ahead and stop that.

And we'll back it up to let's say just kind of right probably

this area here is where it starts to get off.

Not a whole lot more,

but we'll just do a little bit by hand because it doesn't

take much to really throw your track off and make something

really start to look strange.

So I'll just kind of get a few more of these frames done.

And this is what the problem is is this big glare right

here is where it really goes crazy.

So this is definitely helping.

I'm just going to move that back into position.

Just get a few more frames here.

I'm just kind of going through these quickly.

And having this option even helps as I do this by hand.

Now that one, just one frame back, looked a little bit strange.

So let's see what we have here.

I'm just going to move back to 158 and then go back to zero.

So I'm going to hit the left arrow key.

That one right there looks a little bit off.

So let's grab that and pull that down.

This one as well.

And then we're back to kind of where we left off.

So we'll just track backwards a few more times.

Track to the last frame, pull this up a bit.

And I mean, honestly, you can see,

it's a little bit of a tedious process when you have an

area that has a lot of changes like this.

So sometimes you just have to get down and dirty and do it by hand.

And the tracker, no matter how sophisticated it gets over time,

you're probably always going to have some of these difficult tracks.

And unfortunately, sometimes it happens with a screen replacement like this.

So you have to do a little bit of it by hand.

And that's just the way that it is.

Let's go ahead and try to see if we can Track to Start

from frame 112 where we were at.

So it looks like it's doing a pretty good job.

It's pretty close.

Probably not as good as it would look if we did it by hand but pretty good.

Now it looks like we got one point in there that really went crazy.

So right there something went wrong.

So let's go ahead.

And we'll move this one back into position.

And that's just, again, because of that luminous change.

So let's come back here to about frame 101.

And I'm just going to hit the left arrow key.

And we'll just watch this through.

I'm just hitting it a few times.

Just watching that as it lines up in this area here

with the corner of the phone.

And it looks pretty good.

Just want to make sure there's no big major pops like what we just fixed.

And this one looks like it could go back into the corner a little bit better.

Even though that's light, we still know the corner is right there.

And this one as well, we'll move back down.

So I'm just kind of arrowing and moving back.

And once we hit that zero, all our tracking went away.

OK so now, we have our tracking data fixed for Track 4 and 1.

And I want to challenge in between lessons to finish up Track 3 and 2,

make sure those are sticking to their spots.

And then in between lessons, I'm going to do the same thing.

We're going to pick back up in lesson nine.

And then we'll learn how to apply this data and also how to get

that screen to look like it's been replaced with an image or a

video that's playing on the phone.

So stick around.

We're going to learn how to do that in our next lesson.