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Stabilize a shaky clip in Motion

You can use the Stabilize tracking behavior to smooth shaky motion in a video clip or image sequence, such as eliminating teetering from handheld walking shots, or reducing vibrations in automotive shots.

There are three ways to analyze a clip using the Stabilize behavior:

  • Use the behavior’s default advanced motion analysis to evaluate the entire frame of a clip to extract movement data without using onscreen trackers. This automatic analysis works best with real images—artificial images (such as those with no texture) or shots with very strong pans are not recommended.

  • Use onscreen trackers to analyze a reference pattern (a small group of pixels) in the canvas. These are the same trackers used by the Match Move and Analyze Motion behaviors.

  • Use a combination of the advanced motion analysis and onscreen trackers.

Correct a shaky clip using the Stabilize behavior

  1. In the Layers list, select the video clip you want to stabilize, click Behaviors in the toolbar, then choose Motion Tracking > Stabilize.

  2. In the Behaviors Inspector, set the options for the analysis:

    1. Click the Quality pop-up menu, then choose an option:

      • Faster: Allows for a faster operation, but motion analysis is less detailed.

      • Better: Provides a more detailed analysis, but is slower.

    2. To define a specific portion of the clip to be analyzed (and to speed processing), select the Track Region checkbox. See the following task, Limit the area analyzed by the Stabilize behavior.

    3. Click the Method pop-up menu, then choose an option:

      • Stabilize: Locks down an image, removing problems such as camera shake. The resulting effect is similar to footage shot on a camera mounted to a stationary tripod.

      • Smooth: Eliminates camera jitter while maintaining the general motion of the camera. When Smooth is selected, the Translation Smooth, Rotation Smooth, and Scale Smooth parameters become available. See Stabilize controls.

    4. Click the Borders pop-up menu, then choose an option:

      • Normal: Maintains the size of the stabilized footage. Resulting transformations made to the stabilized image may cause moving black borders to appear around the edges of the clip. A very shaky clip results in large black borders.

      • Zoom: Expands the clip to the full size of the canvas, preventing black borders from appearing around the edges of the stabilized clip.

      Canvas showing Stabilize behavior applied to a clip and Borders set to Normal; and Stabilize behavior applied to a clip and Borders set to Zoom

      Note: For suggestions on correcting the black borders, see Remove borders from stabilized clips.

    5. Click the Direction pop-up menu, then choose one of the following options:

      • Horizontal and Vertical: Applies the stabilize transformation to the X and Y positions.

      • Horizontal: Applies the stabilize transformation to the X position.

      • Vertical: Applies the stabilize transformation to the Y position.

    6. Select (or deselect) the Adjust settings:

      • Position: Applies the analyzed position data to the clip. (The X and Y position changes in the footage are smoothed or stabilized.) To stabilize the X and Y position of the shot and leave scale or rotation changes intact, enable Position and disable Scale and Rotation.

      • Scale: Applies any analyzed scale data to the clip. (Scale changes in the footage are smoothed or stabilized.) To stabilize or smooth changes in scale and leave position or rotation changes intact, enable Scale and disable Position and Rotation. (The Scale option is not related to the Zoom option in the Borders pop-up menu.)

      • Rotation: Applies analyzed rotation data to the clip. (Changes in the rotation of the footage are smoothed or stabilized.) To stabilize or smooth changes in rotation in the shot and leave position or scale changes intact, enable Rotation and disable Position and Scale.

      For the smoothest result, select all three Adjust buttons (Position, Scale, and Rotation).

      Note: You can change the Method, Borders, Direction, and Adjust parameters before or after the clip is analyzed.

  3. In the Behaviors Inspector (or HUD), click Analyze (or the right arrows next to the Analyze button).

    The clip is stabilized according to defined parameters. Any motion blur present in the original image remains.

    By default, the Stabilize behavior does not use onscreen trackers to analyze motion or create keyframes in the Keyframe Editor. But you can add trackers for additional smoothing. See the Add trackers to a portion of a stabilize operation task, below.

    Note: The stabilized object’s transformation can be converted to keyframes. See Advanced tracking strategies. When trackers are added to and analyzed with the Stabilize behavior, keyframes are created.

Limit the area analyzed by the Stabilize behavior

When stabilizing a clip, you can define a specific region to be analyzed. During analysis, the area outside this region is ignored. Use this option for faster processing of a clip.

  1. In the Layers list in Motion, select an applied Stabilize behavior.

  2. In the Behaviors Inspector, select the Track Region checkbox.

    A transparent red overlay representing the track region appears in the canvas.

  3. Do any of the following:

    • Change the position of track region: Drag in the region.

    • Resize the track region: Drag a handle on the bounding box of the region. The corner handles simultaneously resize width and height; the top and bottom center handles resize height; the left and right center handles resize width.

    • Resize the track region from its center: Press and hold the Option key while dragging a handle.

    • Change the angle of the track region: Drag the rotation handle in the center of the track region.

      Canvas showing track region boundaries and handles
  4. After defining the track region, click Analyze in the Behaviors Inspector.

    Because analysis takes place in the defined track region, the clip is analyzed more quickly.

Add trackers to a portion of a stabilize operation

If a stabilized clip has a bumpy section that’s not getting smoothed (from an accidental camera bump affecting a range of frames, for example), you can add point trackers to correct that section of the clip.

  1. In Motion, after the Stabilize motion analysis is complete, play the clip to determine the section you want to correct.

  2. Set an Out point for the tracker analysis by positioning the playhead at the frame where you want to stop the analysis, then choose Mark > Mark Play Range Out.

    To yield the best results, use a large range of frames.

  3. Position the playhead at the frame where you want to start the tracker analysis, then do one of the following:

    • Analyze X and Y position changes in the footage: Click the Add button in the Behaviors Inspector to add an Anchor tracker.

    • Analyze changes in X and Y position as well as rotation and scale in the footage: Click the Add button in the Behaviors Inspector once to add an Anchor tracker, then click Add again to add a Rotation-Scale tracker.

  4. In the canvas, position the newly added point tracker on the reference pattern you want to track, then click Analyze in the Behaviors Inspector.

    The play range is tracked, creating track points in the canvas and tracking keyframes in the Keyframe Editor.

    Any stabilization data from the automatic motion analysis is overwritten by the portions of the clip analyzed using the onscreen trackers.

    Tip: When using this strategy to track multiple noncontiguous sections of the clip, use the same tracker to simplify the track and to avoid clutter in the Keyframe Editor.

Modify smoothing parameters

If you’re trying to smooth the motion in a stabilized clip, first try adjusting the smoothing parameters (without reanalyzing the clip).

  1. In the Layers list in Motion, select the Stabilization behavior (that’s already analyzed the clip).

  2. In the Behaviors Inspector, click the Method pop-up menu, then choose Smooth.

  3. Do any of the following:

    • Smooth motion in the X and Y positions: Adjust the Translation Smooth slider.

    • Smooth image rotation: Adjust the Rotation Smooth slider.

    • Smooth an uneven zoom: Adjust the Scale Smooth slider.

      Note: Don’t set the Scale Smooth value above 0 unless you’re positive the clip is being zoomed.

Perform multiple stabilization analyses on a shaky clip

If a clip is particularly shaky, it may be necessary to stabilize the clip more than once to remove camera movement not corrected in the first stabilization analysis.

For a full description of the Stabilize parameters, see Stabilize controls.

Download this guide: PDF

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