WEBVTT

00:00:00.076 --> 00:00:01.746
>> I'm going to show you how to put a 3D object

00:00:01.746 --> 00:00:05.056
into your video using the camera
tracking features in Blender.

00:00:05.056 --> 00:00:08.316
And if you want to follow along with me
in this tutorial, click the link below

00:00:08.316 --> 00:00:10.466
to download this exact video clip.

00:00:10.466 --> 00:00:13.886
So open up Blender and go into the
motion tracking tab by clicking here.

00:00:13.886 --> 00:00:15.336
Then here.

00:00:15.336 --> 00:00:18.326
You can either drag your footage in here,

00:00:18.326 --> 00:00:20.596
but I'm going to click open
and select our video clip.

00:00:20.676 --> 00:00:24.156
The first thing I'm going to do is
click on set scene frames so that in

00:00:24.156 --> 00:00:26.786
and out points matches the
length of the video clip.

00:00:26.786 --> 00:00:29.566
Then click on prefetch to
load the clip into memory.

00:00:29.606 --> 00:00:32.156
Then under tracking settings,
I'm going to set the motion model

00:00:32.156 --> 00:00:34.986
to affine and the match to previous frame.

00:00:35.096 --> 00:00:37.656
Affine takes into account the
perspective changes in the shot.

00:00:37.656 --> 00:00:41.846
And previous frame basically just tracks the
pattern from the current frame to the next one.

00:00:42.016 --> 00:00:43.866
Then I'm going to tick normalize.

00:00:43.896 --> 00:00:46.146
This makes sure that if there's
any changes in light

00:00:46.146 --> 00:00:48.816
in the video clip, the track
is not affected by it.

00:00:49.006 --> 00:00:53.276
Now that's done, I'm going to go to the
first frame by pressing shift arrow,

00:00:53.476 --> 00:00:55.736
and then click on detect features.

00:00:55.736 --> 00:00:58.196
Now these boxes on the scene
are tracking markers.

00:00:58.256 --> 00:01:00.866
They track points of contrast within the clip.

00:01:00.936 --> 00:01:05.306
Now I want more tracking markers, so I'm going
to click on this little tab on the bottom left.

00:01:05.346 --> 00:01:08.106
I'm going to change the threshold to 0.1.

00:01:08.106 --> 00:01:10.826
I'm going to change the distance to, say, 50.

00:01:10.906 --> 00:01:13.766
And I'm going to set the margin
from the edge of the frame,

00:01:13.766 --> 00:01:16.916
or the borders of the frame, to about 50 pixels.

00:01:17.056 --> 00:01:21.006
Now if you go into our tracking setting
over here, we need to set the value

00:01:21.006 --> 00:01:24.096
of this margin lower than the
value of the other margin.

00:01:24.096 --> 00:01:25.846
So I'm going to set this to about 40.

00:01:25.846 --> 00:01:29.936
Now, with all the markers selected, I
want to press control T to track forwards.

00:01:31.136 --> 00:01:31.956
Yeah, brilliant.

00:01:32.026 --> 00:01:35.176
Once you've finished tracking forwards,
making sure all the markers are highlighted.

00:01:35.176 --> 00:01:37.436
And if you want to highlight all the
markers, just hover your mouse over here

00:01:37.436 --> 00:01:40.396
and press A. Now I'm going
to press H to hide them all.

00:01:40.396 --> 00:01:44.376
And while still being on the last frame, I'm
going to once again click on detect features

00:01:44.456 --> 00:01:46.286
to bring up all the tracking points.

00:01:46.286 --> 00:01:48.716
And I'm fully happy with these tracking
markers so I'm going to track backwards

00:01:48.716 --> 00:01:52.976
by pressing shift control
T, or control shift T. Nice.

00:01:53.646 --> 00:01:55.516
Next, I want to reveal all the trackers,

00:01:55.516 --> 00:01:58.266
so I'm going to press alt H
to bring up all the trackers.

00:01:58.426 --> 00:02:00.606
Now we have a couple of trackers
that are problematic.

00:02:00.606 --> 00:02:03.286
For instance, maybe these ones
here that follow the cars.

00:02:03.286 --> 00:02:05.616
So what I'm going to do, you
can either delete them manually

00:02:05.616 --> 00:02:07.656
by selecting them and pressing X to delete.

00:02:07.656 --> 00:02:11.516
Or you can also click on solve right here.

00:02:12.056 --> 00:02:17.816
Then select cleanup to get rid of any glitchy
tracks or tracks that have high error value.

00:02:17.816 --> 00:02:19.696
I'm going to click on filter tracks.

00:02:19.696 --> 00:02:22.166
And, as you can see, it's selected
all the markers that are glitchy.

00:02:22.166 --> 00:02:26.926
So all I have to do is hold my mouse
over the footage, press X and delete.

00:02:26.926 --> 00:02:30.006
I'm going to go halfway throughout
the clip and select filter tracks.

00:02:30.006 --> 00:02:30.766
And there's none.

00:02:30.946 --> 00:02:34.356
And just to make sure, I'm going to go to
the last frame and select filter tracks.

00:02:34.486 --> 00:02:36.016
And there's none showing up, so that's good.

00:02:36.226 --> 00:02:42.226
Okay, so next, while still on the solve tab, I'm
going to select focal length and optical center.

00:02:42.486 --> 00:02:47.036
Then for keyframe A and B, so you want to pick
a frame range where the camera is moving a lot

00:02:47.036 --> 00:02:49.216
so Blender can actually track the shot.

00:02:49.216 --> 00:02:52.716
So I'm going to pick a frame range
between 100 to, say, frame 180.

00:02:52.816 --> 00:02:56.526
I've just seen some tracks that are
wild, so I'm going to delete them now.

00:02:56.726 --> 00:02:58.316
Like so. Get rid of this.

00:03:01.166 --> 00:03:02.966
Get rid of that one.

00:03:02.966 --> 00:03:03.696
Yeah, that's cool.

00:03:03.696 --> 00:03:04.176
That's fine.

00:03:04.176 --> 00:03:06.966
Now I'm going to click on solve camera motion.

00:03:07.306 --> 00:03:12.346
And we have a solve error
of 0.35 which is fantastic.

00:03:12.456 --> 00:03:14.246
Any solve error below a pixel is good.

00:03:14.246 --> 00:03:16.716
And anything below 0.5 is great.

00:03:16.716 --> 00:03:20.616
Any solve error above one pixel is
not a good track, I wouldn't use it.

00:03:20.686 --> 00:03:23.796
Now in the scene setup, on the
left, click on set as background.

00:03:23.796 --> 00:03:25.996
And, as you can see, it puts the
video in the background of the camera.

00:03:26.156 --> 00:03:28.966
Then I'm going to select setup tracking scene.

00:03:31.376 --> 00:03:34.986
Next, I'm going to hold shift
and select these three tracks,

00:03:35.306 --> 00:03:37.926
and click on floor to set the floor plane.

00:03:37.926 --> 00:03:41.686
Now I'm going to set the origin of my scene by
clicking this track and selecting set origin.

00:03:41.686 --> 00:03:46.526
Just to make sure that's the middle of
my scene, I'm going to delete this cube

00:03:46.736 --> 00:03:48.926
and I'm going to go into the layout view.

00:03:48.926 --> 00:03:50.916
So I'm going to click this tab.

00:03:51.946 --> 00:03:56.286
Then I'm going to press zero on my
numpad to look through the camera.

00:03:56.286 --> 00:04:01.526
And I'm going to click this little scroll down
button here and I'm going to select 3D cursor.

00:04:01.526 --> 00:04:04.966
Once I've selected 3D cursor, I'm going
to make sure my camera is highlighted.

00:04:05.016 --> 00:04:10.406
And I'm going to place R for rotation and I'm
just going to line up the camera's perspective

00:04:10.536 --> 00:04:15.436
so that the Y direction is going
along the road and the X is going

00:04:15.436 --> 00:04:17.956
across the road, just like that, in this field.

00:04:17.956 --> 00:04:18.956
Just so it lines up like that.

00:04:18.956 --> 00:04:19.456
That's perfect.

00:04:19.456 --> 00:04:23.296
I'm going to select the scroll down button
again and select bounding box center.

00:04:23.296 --> 00:04:25.796
Next, I'm going to change the scale.

00:04:25.796 --> 00:04:30.616
And I'm going to move the plane about here.

00:04:30.616 --> 00:04:31.536
Yeah, that's nice.

00:04:31.536 --> 00:04:32.086
That's perfect.

00:04:32.086 --> 00:04:32.886
I'm happy with that.

00:04:33.046 --> 00:04:36.856
Now I'm going to press space bar just to make
sure that the plane is sticking to the ground.

00:04:36.856 --> 00:04:37.556
Yeah, that looks good.

00:04:37.746 --> 00:04:39.746
Now we can easily put a 3D
object into the scene.

00:04:39.746 --> 00:04:42.516
I'm going to press shift A,
mesh, and select the monkey.

00:04:42.516 --> 00:04:44.876
I'm going to place the monkey so
that it's kind of facing the camera.

00:04:44.876 --> 00:04:47.106
Also so that it's just sitting above the plane.

00:04:47.276 --> 00:04:47.926
Yeah, that's good.

00:04:48.186 --> 00:04:50.896
I'm going to decrease the scale a bit.

00:04:51.686 --> 00:04:52.436
Yeah, perfect.

00:04:52.436 --> 00:04:55.996
Now I'm going to go into render view by
either pressing Z then clicking render.

00:04:55.996 --> 00:04:58.376
Now, as you can see, we can't
really see the video footage.

00:04:58.506 --> 00:05:01.786
But to show the video clip, click
on the render properties tab,

00:05:01.896 --> 00:05:03.776
go to film, then select transparent.

00:05:03.776 --> 00:05:06.316
And we can now view the clip through the camera.

00:05:06.316 --> 00:05:07.856
Now, as you can see, we don't
have any shadows cast.

00:05:07.856 --> 00:05:09.796
That's because we need to bring the ground plane

00:05:09.796 --> 00:05:12.096
from the ground collection
into the foreground collection.

00:05:12.166 --> 00:05:13.476
So I'm going to do that.

00:05:13.776 --> 00:05:17.616
I'm going to change the light to a
sunlight by clicking on this light.

00:05:17.956 --> 00:05:20.866
And clicking on the light
properties and selecting sun.

00:05:20.866 --> 00:05:23.746
I'm going to decrease the
power to about three or five.

00:05:23.946 --> 00:05:28.456
And I'm going to change the angle to match
where the sun is coming from in our clip.

00:05:31.046 --> 00:05:35.226
And I'm going to change the angle
so that the shadows aren't so harsh.

00:05:35.226 --> 00:05:36.176
Nice. Perfect.

00:05:36.436 --> 00:05:39.916
Now there's a lot of other things you can do
to increase the realism of this object fitting

00:05:39.916 --> 00:05:44.336
in this clip, like adding realistic reflections,
lighting with a HDRI, adding blur and glare.

00:05:44.336 --> 00:05:46.016
But I'll cover that in another tutorial.

00:05:46.066 --> 00:05:49.046
There's also several other ways you
can track a more difficult shot,

00:05:49.046 --> 00:05:51.016
and I'll also cover that in another tutorial.

00:05:51.016 --> 00:05:53.776
But, for now, I hope you learned something
new and any questions let me know.

00:05:53.826 --> 00:05:54.806
And I'll see you in the next one.

00:05:55.056 --> 00:05:55.446
Take care.

00:05:55.446 --> 00:05:55.776
Cheers.

00:05:56.516 --> 00:06:14.230
[ Music ]