Timing Controls in the Properties Inspector
Media layers (images and movie clips as opposed to Motion-created shapes) have timing
parameters in the Properties Inspector. Click Show on the right side of the Timing category
to reveal these timing controls.
Still images and other layers without an inherent time dimension have a reduced set of
Timing controls.
Time Remap:
Sets how time is remapped in the clip. Use this pop-up menu to set Constant
Speed or Variable Speed.
• Constant Speed: Retimes the entire clip using the same value.
• Variable Speed: Allows you to animate the speed of the clip over time.
Speed:
A value slider that sets the speed of the clip as a percentage. The default is 100%.
Values lower than 100 play back the clip more slowly than its original speed and also
extend the duration of the clip. Values higher than 100 play back the clip faster than its
original speed and shorten the duration of the clip.
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This parameter appears only when Time Remap is set to Constant Speed.
Retime Value:
Displays the time value of the clip at a given frame. When you set Time
Remap to Variable Speed, two keyframes are generated at the first and last frame of the
clip. The two default keyframes represent 100% constant speed. Adding keyframes to
this parameter and assigning them different Retime Values makes the speed of the clip
ramp from one speed to another.
This parameter appears only when Time Remap is set to Variable Speed.
In:
Sets the In point of the layer, in both constant and variable speed modes. Adjusting
this parameter moves the layer In point to the specified frame without affecting the
duration of the layer.
Out:
Sets the Out point of the layer, in both constant and variable speed modes. Adjusting
this parameter moves the layer Out point to the specified frame without affecting the
duration of the layer.
Duration:
Sets the total duration of the layer. If Time Remap is set to Constant Speed,
adjusting Duration will also affect the Speed and the Out point. If Time Remap is set to
Variable Speed, adjusting Duration does not affect variable speed playback.
Reverse:
This checkbox controls whether the clip is played back in reverse.
Frame Blending:
Sets the method used to determine how the image is blended during
each frame of playback. The Frame Blending pop-up menu contains the following items:
• None: Displays the frame from the original clip nearest the source frame.
• Blending: The default setting. Displays a blend of the individual pixels of adjacent
frames.
• Motion-Blur Blending: Applies a motion blur algorithm to the blended frames.
• Optical Flow: Uses an optical flow algorithm to blend the two frames surrounding the
desired frame. Using this method affects playback performance most significantly. To
display frames properly, Motion analyzes the clip to determine the directional movement
of pixels. Only the portion of the clip used in the project (the clip between the In and
Out points) is analyzed.
When you choose Optical flow, an analysis indicator appears in the lower-left corner
of the Canvas.
Analysis indicator
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If you play back the project before the analysis is complete, the clip will appear as if
Frame Blending is set to None. When the analysis is complete, the indicator disappears,
and the clip will play back properly. You can view more detailed information about the
clip analysis and stop the process before it is finished.
You can perform optical flow analysis on multiple clips simultaneously. The clips are
processed in the order—the first clip you apply optical flow to is processed first, and
so on.
Note: The more motion contained in a clip, the longer the analysis takes.
For information on pausing, reordering, or stopping a clip analysis, see
Displaying and
Editing Retiming Tasks
.
Important:
When importing interlaced footage and using the Optical Flow method for
frame blending, be sure the Field Order parameter (in the Media Inspector) is assigned
to the correct value. Otherwise, artifacts might appear in the retimed layer.
End Condition:
A pop-up menu that lets you set how playback continues when the end
of the clip is reached. There are four options:
• None: The default setting. The layer’s duration in your project is equal to the duration
of its source media file.
• Loop: When the last frame of the clip is reached, the clip loops back to the first frame
and plays again. This can cause a jump in the clip’s apparent playback unless the clip
was designed to loop seamlessly.
• Ping-Pong: When the last frame of the clip is reached, the next iteration of clip playback
is reversed. If you set a clip of a ball rolling on the floor to loop with the Ping-Pong
option, it would appear to roll forward, then backward, then forward again for the
duration of the layer. The Ping-Pong option lets you extend the duration of some video
clips more smoothly than the Loop option.
• Hold: This freezes the last frame of the clip for the amount set in the End Duration
slider.
Note: When using the Hold option with interlaced footage, ensure that field order is
properly set in the Media Inspector. To modify a clip’s field order, select the clip in the
Media list, then choose an option from the Field Order pop-up menu in the Media
Inspector.
End Duration:
A slider that lets you set the number of frames by which the clip is extended
at the end of its duration. This value can be adjusted only if End Condition is set to a value
other than None.