Options for Controlling Parameter Changes at Keyframes
You can select from the following options for controlling parameter changes at keyframes:
 | |
Shelf — The parameter value does not change between keyframes and
then changes abruptly to the new value. Some applications call this
Hold.
|
Use Shelf to hold a parameter value for a fixed length of time. For
example, you can use Shelf with the Position parameters to create a
PIP that appears to "pop" to a new location at each keyframe.
| |
Linear — The parameter value ramps smoothly between keyframes
but then changes abruptly at each keyframe. The change in parameter
value at a keyframe happens with no ease-in or ease-out.
|
Effects with standard keyframes make linear parameter changes (with
the exception of Spline for motion paths and Acceleration for other
parameters). With advanced keyframes, you can use the Linear
interpolation option for some parameters and not for others, depending
on the effect you want to achieve.
| |
Spline — The parameter value changes smoothly at each keyframe,
creating a simple ease-in or ease-out effect. Spline is sometimes called
Natural Spline or Cardinal Spline because the line representing the
parameter value always goes precisely through each keyframe.
|
With two keyframes, the parameter value changes slowly at the
beginning of the effect, speeds up the rate of change, and then slows
down to come to rest gently at the end of the effect. Use three
keyframes to create an arc.
Use the Spline interpolation option (or the BΘzier interpolation option)
for any parameter for which you want to avoid abrupt changes, such as
Scaling or Border width.
| |
BΘzier — The BΘzier interpolation option is similar to the Spline
interpolation option, in that the parameter value changes smoothly at
each keyframe. In addition, the BΘzier interpolation option provides
direction handles at each keyframe. You adjust the rate at which the
parameter value changes by manipulating the direction handles.
|
When you click a direction handle and drag it, you change the height
and angle of the curve. The curve responds as if you were gently
tugging it like a piece of string. The curve remains anchored to the
keyframes on either side of the active keyframe.
Use the BΘzier interpolation option (or the Spline interpolation option)
for any parameter for which you want to avoid abrupt changes.
You can adjust BΘzier curves in the following ways:
