Single-Point Tracking in Blender
Preview
1. Tracking the Footage
Step 1
Open
Blender.
Step 2
Click on Editor and select Movie Clip Editor.
Step 3
Click
on Open to import the footage into the Movie Clip Editor.
Step 4
Go
to the folder with the image sequence of the footage. Select the first frame
and click the Open Clip button.
Step 5
Now you can see the footage inside the movie clip editor window. Click on Prefetch Frames button to load the image sequence in the RAM. Alternatively, press the P key.
Step 6
Try to search for a good contrast point to track the footage. Once you have searched a point, press and hold the Ctrl key and secondary-click with the mouse button onto that point.
A tracker appears on the footage.
Step 7
Click on Track Forward button to track the footage.
Step 8
Within
a couple of seconds, the footage gets tracked. You can play the footage to
check the reliability of the track. In my case, the footage has been tracked
without any problem.
2. Compositing of the Footage in Node Editor
Step 1
The next stage is to work in Compositor mode. Click Editor and select Node Editor.
Step 2
This is how the default interface of the node editor looks. If you've ever worked in Fusion or Nuke, you will find the process quite familiar. Click on little tiny + sign on the left.
Step 3
It
opens the node panel.
Step 4
Go
to Input > Movie Clip. The Movie Clip node appears inside the Node
Editor window.
Step 5
Following the same way, go to Output > Composite and Viewer. You get Composite and Viewer nodes as well.
Step 6
In
the Movie Clip node, click on Open and import the background footage.
Step 7
Connect the Movie Clip node’s image string to the Viewer node’s image string.
Alternatively, with the Movie Clip node selected, press and hold Ctrl-Shift together and click on Movie Clip node. This will connect together both nodes.
Step 8
Turn on Backdrop option to see the footage inside the compositor.
Step 9
Go
to Input > Image. The Image node appears inside the Node Editor window. I'm using this
node to import the foreground image which I want to place over the background
footage.
Step 10
In
the Image node, click on Open and import the foreground image.
Step 11
You
can see the foreground image, by pressing and holding Ctrl-Shift together and click on Image node. This is a simple sign image with alpha channel.
Step 12
It’s
time to merge both nodes together to see the final composited result. So, go to
Color > Mix. The Mix node appears inside the Node Editor window.
Step 13
Drag and drop the Mix node between the Movie Clip and Viewer Nodes.
Step 14
Connect the Image node’s image string to the Mix node’s image string.
Step 15
Turn
on Alpha option of the Mix node.
Step 16
The
size of the foreground image is quite big and it overlaps the background footage.
Go to Distort > Transform. The Transform node appears inside the Node Editor window. I will use this
node to scale down the size of the foreground image.
Step 17
Drag
and drop the Transform node between
the Image and Mix Nodes. I've used its transform values to position and scale
the image according to the need.
Step 18
Go to Input > Track Position. The Track Position node appears inside the Node Editor window.
Step 19
Click Browse ID Data icon of the Track Position node. Select the footage which has been tracked.
Step 20
You get two new options-Camera and Tracking Data. Click on Camera and select the Blender’s camera. Click on Tracking Data and select the tracker from the list.
Step 21
Go to Distort > Transform once again. A new Transform node appears inside the Node Editor window. I will use this node to connect with the Track Position node.
Step 22
Drag and drop the new Transform node between the earlier Transform node and Viewer Nodes.
Step 23
Connect X and Y strings of Track Position node to the new Transform node’s string respectively.
Change the Track Position node’s mode from Absolute to Relative Frame.
Step 24
The work is done. Play the footage and you will see the foreground image going perfectly with the background footage.
A little bit, however, of post production work is needed here.
Step 25
Change
the Mix node to Overlay.
See how the foreground image now mixes with the background footage perfectly.
Step 26
You
can add a Blur node also. Applying a
tiny amount of blur matches the foreground image with the background image
perfectly.
Conclusion
In this part of the tutorial series, I showed you how to create single-point tracking. In the next part of the tutorial, I will show how to set up tracking from two points.