Stabilize Jittery Footage in Adobe After Effects

The first step is to download the AE project and footage from the tutorials page here.

Open up the comp and select the that is the single layer in the timeline. Go to the Animation menu and select . Note that in some cases you might want to scale the footage up by 10 percent. As AE stabilizes the motion, the frame will shift, resulting in white space around the edges. In our case, all the white space is outside the action safe area.

This opens up the movie in a separate tracking window, with the tracking UI and widget. The tracking widget is a "+" symbol (the crosshairs) within a small square, all of which is inside a larger square.

The tracking widget’s crosshairs determine the tracking point and the layer is offset relative to this point. You don’t want to move the crosshairs during stabilization or tracking. It’ll completely distort the results. Once you’ve found a nice home for it, leave it alone. If you find you need to adjust it, you’ll need to restart the tracking process.

The smaller box defines the pattern that the tracker is looking for. The MT works by taking this pattern and looking for it in each frame. When you’re stabilizing footage, it finds this pattern and moves the entire frame so the pattern falls in exactly the same spot as it did in the previous frame. How much the frame has to be moved is the offset amount. The goal is to have the tracker locate this pattern in each frame and have the MT line the pattern up so that every frame has it in the same location. (More on how to select the pattern in Step 4.)

The larger box is the search area. This is the area that the MT will look in for the pattern. Be warned: the larger you make this, the slower the MT will be and the more likely a similar but different pattern will be found. This will make the MT jump off track. But you do need to make this large enough that the pattern will be found in all frames. If the footage is really jumpy, the search area will have to be larger than the search area for footage with only a slight jitter. You can change search areas as the track progresses. If the footage is only jumpy for a second, you can make the search area larger or change the pattern for just those frames.

The key to motion tracking or stabilization is to find a pattern that is unique in the search area and is easily identifiable by the MT. Not by your eye, but by the MT’s calculations. People can easily identify all sorts of patterns and track them. Computers handle this task literally and it’s not something they excel at. But a pattern that’s easy for a computer to keep track of has several key attributes: 1) high contrast; 2) sharp, perpendicular edges; 3) no repetitions; 4) is not obscured during the length of the footage.

This is where the black art of motion tracking comes in. The pattern doesn’t have to have all these attributes, but the closer you get to fulfilling them, the easier the job will be. Also, since the footage re-positioned each frame to line up the pattern, you end up with transparent areas around the edge. In this case, that’s only going to be noticeable on the extreme edges outside of Action Safe. If the movement is more noticeable, you might want to scale the footage up by 5 to 10 percent.

Click and drag in the small square and move the crosshairs so they are on the corner of one of the buildings in the lower, right corner of the image.

This spot worked well for me, but there are other spots that would have worked too. Modify the small square a bit, as shown, then shrink the large square down so it forms a loose fit around it.

Make sure the Time Marker is at 00:00 and hit the play button on the Tracking Palette.

Sometimes it takes some trial and error to find a good tracking pattern. The pattern I used should work extremely well, but try and find another one. If you don’t find a good pattern, our tracking point will lose its way. The crosshairs start wandering away from the cluster of points that were created in the first part of the footage. If you can’t get it to work there are a couple of things to try.

If your original pattern changes (like the lighting in this footage) you may need to make adjustments. Sometimes, this is as easy as enlarging the pattern square a little. Sometimes it requires some creative thinking. (Notice I didn’t say "requires thinking outside the box." In some parts of the world uttering bad, overused clichà©is cause for imprisonment, forced labor and listening to Vogon poetry.)

The pattern square does not have to be centered around the crosshairs. If you enlarge the search area to include the entire building we can select a different pattern, such as the large, bright window below our original pattern.

In each case you’ll need to press the play button on the Tracking Palette to start the process. Remember not to move the crosshairs themselves. This will mess up the stabilization.

Once you get the track done, click the Apply button. This will transfer all the tracking info to your Anchor Point position and offset the layer as needed.

Now you can close the tracking window and go back to your main comp. You should have a nicely stabilized piece of footage. If you still have a little bit of jiggle you can try starting the process over from scratch. Don’t worry; it took me a couple of tries to find a good tracking spot. You can also pre-comp your footage and apply a new stabilization to that.

After Effects stabilizes footage well, but sometimes, you’ll still have just a little bit of jitter. Applying stabilization a second time will get rid of it. Think of it as two-pass stabilization: one-pass to get rid of the shaking, and another pass to get rid of the smaller sub-pixel jitters.

That’s it! If you’re still having trouble you can go into the Finished Comp and double click on the Tracker 1 that’s applied to the layer. This will open up the MT window and show you exactly where I positioned the tracking point.

Jim Tierney
President
Digital Anarchy

Jim Tierney has worked on numerous award-winning products from companies like MetaCreations, Atomic Power and Cycore. After working on Adobe After Effects plug-ins for almost a decade, he thought it was finally time to get out there and do some of his own. As "Chief Executive Anarchist," Jim conceptualizes and designs Digital Anarchy products.

Motion tracking and stabilization can seem like a bit of a black art. But it’s really not as difficult as it first might appear. The Motion Tracker/Stabilizer in After Effects, while still not exactly on a par with Shake or Flame, will bring fluid movement to a jittery piece of footage.

The original raw footage I used here comes from stock agency Thought Equity (www.thoughtequity.com). This is a cropped, SD resolution chunk of one of their HD time-lapse stock clips. The footage needed to be stabilized before it would actually be useful to anyone.

After Effects’ Motion Tracker/Stabilizer is much improved from earlier versions and for the vast majority of jobs it works very well. We’re going to discuss the stabilization features of the Motion Tracker, and then tackle tracking in a future tutorial. The techniques for stabilizing and tracking are the same, but tracking requires some additional work. Unfortunately, none of the stabilization techniques work with mentally unstable clients. That’s a completely different tutorial.

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