Time Displacement Controls (Pro Only); To Use The Time Displacement Effect (Pro Only) - Adobe AFTER EFFECTS 7.0 Manual

The Time Displacement effect automatically replaces pixels across time without keyframes. However, you can also
set keyframes for other controls to vary the effect over time.
To better understand how pixels are displaced in time, think of the displacement occurring in steps, as follows:
After Effects overlays the displacement map layer on top of the effect layer (the layer you are distorting). If the
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dimensions of the displacement map are different from those of the effect layer, you can specify whether the map is
centered or stretched to fit.
2 You specify a maximum displacement amount, in seconds.
After Effect uses the luminance value of each pixel in the displacement map to calculate the displacement of the
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corresponding pixel in the effect layer based on the maximum displacement amount.
In grayscale images, the luminance value range extends from 0 to 255, which is converted into a scale ranging from
-1 to 1. A luminance value of 0 produces maximum backward displacement, meaning that pixels at the current time
are replaced by pixels from a previous time. A luminance value of 255 produces maximum positive displacement,
meaning that pixels at the current time are replaced by those at a future time. A luminance value of 128 produces no
displacement. For other values in grayscale displacement maps, you can calculate the displacement amount, in
seconds, using the following equation:
Displacement amount in seconds = maximum_displacement_time * (2 * (luminance value – 128)/256)
After Effects displaces each pixel in the image by replacing a pixel in the image at the current time with the pixel
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in the same position at another time. The other time is the displacement amount in seconds for the pixel, calculated
in step 3.
Suppose you specified 2 seconds as the maximum time displacement. After Effects finds the luminance value of each
pixel in the displacement map, and then replaces the corresponding pixels at the current time with pixels from
another time based on the maximum time of 2 seconds. A luminance value of 255 in the displacement map replaces
that pixel with the pixel 2 seconds ahead in the same position. A luminance value of 42 replaces that pixel with the
pixel 1.34 seconds behind in the same position.

Time Displacement controls (Pro only)

Time Displacement Layer
Max Displacement Time (sec)
current time. Note that only luminance values of 0 or 255 (maximum darkness and maximum brightness) produce
the maximum time. All other luminance values produce times less than the maximum time.
Sets the number of frames per second in which to replace pixels. Typically, this value should
Time Resolution (fps)
not be greater than the frame rate of the affected layer. Increasing Time Resolution can significantly increase
rendering time.
Resizes the Time Displacement Layer to match the dimensions of the layer you are distorting. If
Stretch Map to Fit
this option is not selected, the time displacement layer is centered in the composition.

To use the Time Displacement effect (Pro only)

1 In the Composition panel, display both the layer you want to distort and the displacement map layer.
Hide the displacement map layer by clicking the Video switch in the Timeline panel.
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In the Composition panel, select the layer you want to distort.
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4 Choose Effect > Time > Time Displacement.
Specifies the layer to use as the displacement map.
Sets the maximum time, in seconds, from which pixels are replaced, before or after the
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