Reverse a layer’s playback direction, Reverse keyframes without reversing layer playback, About time-remapping – Adobe After Effects CS3 User Manual
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AFTER EFFECTS CS3
User Guide
220
Reverse a layer’s playback direction
When you reverse a layer’s playback direction, all keyframes for all properties on the selected layer also reverse order.
The layer itself maintains its original In and Out points relative to the composition.
Note: For best results, precompose the layer and then reverse the layer inside the precomposition. This is the most
accurate way to reverse footage. For more information on this process, see “About nesting and precomposing” on
page 113.
1
In a Timeline panel, select the layer you want to reverse.
2
Choose Layer > Time > Time-Reverse Layer, or press Ctrl+Alt+R (Windows) or Command+Option+R (Mac OS).
Reverse keyframes without reversing layer playback
You can select and reverse keyframes across multiple layers and properties, but each set of keyframes for a property
is reversed only within its original time range and not that of any other selected property. Markers in the Timeline
panel are not reversed, so you might need to move markers after reversing keyframes.
1
In the Timeline panel, select a range of keyframes you want to reverse.
2
Choose Animation > Keyframe Assistant > Time-Reverse Keyframes.
About time-remapping
You can expand, compress, play backward, or freeze a portion of a layer’s duration using a process known as time-
remapping. For example, if you are using footage of a person walking, you can play footage of the person moving
forward, and then play a few frames backward to make the person retreat, and then play forward again to have the
person resume walking.
When you apply time-remapping to a layer containing audio and video, the audio and video remain synchronized.
You can remap audio files to gradually decrease or increase the pitch, play audio backward, or create a warbled or
scratchy sound. Still-image layers cannot be time-remapped.
Aharon Rabinowitz provides a tutorial that shows how to use time-remapping to do lip-synching; this same basic
concept can be used for many kinds of character animation:
You can remap time in either the Layer panel or the Graph Editor. Remapping video in one panel displays the results
in both. Each provides a different view of the layer duration:
•
The Layer panel provides a visual reference of the frames you change, as well as the frame number. The panel
displays the current-time indicator and a remap-time marker, which you move to select the frame you want to play
at the current time.