User Manual

Table Of Contents
In a locked-off camera shot where a car is moving through the frame, the background does not
move, so it produces small, or slow, vectors, while the car produces larger, or faster, vectors.
The Depth Ordering in this case is Fastest On Top since the car draws over the background.
In a shot where the camera pans to follow the car, the background has faster vectors, and the
car has slower vectors, so the Depth Ordering method is Slowest On Top.
Clamp Edges
Under certain circumstances, this option can remove the transparent gaps that may appear on
the edges of interpolated frames. Clamp Edges causes a stretching artifact near the edges of
the frame that is especially visible with objects moving through it or when the camera is moving.
Because of these artifacts, it is a good idea to use Clamp Edges only to correct small gaps
around the edges of an interpolated frame.
Edge Softness
This slider is displayed only when Clamp Edges is enabled. The slider helps to reduce the
stretchy artifacts that might be introduced by Clamp Edges.
If you have more than one of the Source Frame and Warp Direction checkboxes turned on, this
can lead to doubling up of the stretching effect near the edges. In this case, you‘ll want to keep
the softness rather small at around 0.01. If you have only one checkbox enabled, you can use a
larger softness at around 0.03.
Source Frame and Warp Direction
These checkboxes allow you to choose which frames and vectors create the in-between
frames. Each method ticked on will be blended into the result.
Prev Forward: Takes the previous frame and uses the Forward vector to interpolate the
new frame.
Next Forward: Takes the next frame in the sequence and uses the Forward vector to
interpolate the new frame.
Prev Backward: Takes the previous frame and uses the Back Forward vector to
interpolate the new frame.
Next Backward: Takes the next frame in the sequence and uses the Back vector to
interpolate the new frame.
Optical Flow Options: These settings tweak the optical flow analysis. Please see the “Advanced
Controls” section for the Optical Flow node earlier in this chapter.
Common Controls
Settings Tab
The Settings tab in the Inspector is also duplicated in other Optical Flow nodes. These common
controls are described in detail in the following “The Common Controls” section.
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