Keyframe Thinning

When a parameter contains at least one keyframe, or when the Record button is on, a keyframe is added every time you modify a parameter at a new playhead position. If you animate while the project is playing, you create a keyframe at every frame. This doesn’t cause a problem until you want to modify the curve.

In many cases, the curve created by your animation can be represented using fewer keyframes. Often, this provides a smoother rate of change and lets you take advantage of interpolation methods such as Bezier or Continuous.

You can simplify your keyframes in two ways: while you are recording them, or afterwards, by simplifying an existing animation curve using the Reduce Keyframes command in the Animation menu for that parameter.

To reduce keyframes in an animation curve

Click the Animation menu (the fifth column in the Keyframe Editor parameter list), then choose Reduce Keyframes from the Animation menu.
The Reduce Keyframes dialog appears.
Adjust the Error Tolerance and Smoothing parameters to obtain the curve you want.

Figure. Keyframe Editor showing a parameter with reduced keyframes.

Recording Options

The Recording Options dialog allows you to adjust the Keyframe Thinning setting or to disable recording during playback.

The Keyframe Thinning setting applies to recording animation while playing back. This setting has no effect on ordinary keyframing.

To access Recording Options

Do one of the following:

Choose Mark > Recording Options (or press Option-A).
Double-click the Record button (under the Canvas).
The Recording Options dialog appears. Choose a thinning option, then click OK.

The Recording Options dialog contains the following options:

Keyframe Thinning: Select one of three keyframe-thinning options:
- Off: No thinning is applied. Keyframes are added at every frame where the parameter is changed.
- Reduced: Motion eliminates keyframes that can easily be replaced with a simple curve.
- Peaks Only: Only keyframes with dramatic value changes are recorded.
Don’t record keyframes during playback: Select this checkbox if you don’t want keyframes to be recorded while the project is playing back.

Disabling Animation While Playing

If the Record button is on or a parameter contains at least one keyframe, keyframes are added when you make parameter adjustments. To prevent creating accidental animation, you can restrict automatic keyframing so it happens only when the project is not playing.

To disable animation recording while playing

Choose Mark > Recording Options.
The Recording Options dialog appears.
Select “Don’t Record keyframes during playback.”
Click OK.