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Chapter 13 Special FX
When Does a Timewarp Clip End?
By strict definition, the destination clip ends where the straight blue line exits the diagram grid.
This means that logically it can be played only to the point at which the last frame (interpolated from the
source clip) was played back. Beyond this point, the last source clip frame is played back as a still and
continues this way for as long as you wish.
However, basically, the destination clip ends whenever you want it to. You simply have to trim the clip at
the appropriate position on the Timeline (also see “Standard Applications” on page 800).
The vertical extension of the grid in the upper diagram indicates the actual length of the source clip
Media File. You cannot set Key Frames outside this grid.
There is no limit to the horizontal extension to the right and left. In theory at least, the destination clip
can be endless.
Dynamic Acceleration/Deceleration
When multiple Key Frames are used, you can generate dynamic Timewarp effects.
Example:
Accelerate-Decelerate-Stop-Reverse-Accelerate-Decelerate
This Timewarp clip has three Key Frames linked by curves. The parameters of the first and last Key Frame
are the same: A factor of 1.0 (100% play speed), i.e. standard playback.
The center Key Frame is defined in the speed diagram as -100% (-1.0), i.e. at this point, the destination
clip should play at a normal speed but in reverse.
Speed
-100%
100%
0%
Source
clip
Faster
< Stop
Reverse
< >
Slower
< >
Slower
< >
Stop >
Faster
< >
< >