User Manual

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 at the end of this chapter in “The Common Controls” section.
Smooth Motion [SM]
The Smooth Motion node
Smooth Motion Node Introduction
The Smooth Motion node smooths various AOV (Arbitrary Output Variables) channels in a clip
using optical flow to look at neighboring frames. It can be used for smoothing the Disparity
channel in a stereo 3D clip, where it helps reduce temporal edge/fringing artifacts, but it can
also smooth a wide range of channels like vectors, normals, and Z.
It is required that the image connected to the input on the node have precomputed Vector and
Back Vector channels; otherwise, this tool prints error messages in the Console window.
Check on the channels you want to temporally smooth. Be aware that if a channel selected for
smoothing is not present, Smooth Motion will not fail, nor will it print any error messages.
It can also be used to smooth the Vector and Back Vector channels; however, sometimes, this
can make the interpolated results worse if there are conflicting motions or objects in the shot
that move around erratically, jitter, or bounce rapidly.
TIP: You can use two or more Smooth Motion nodes in sequence to get additional
smoothing. With one Smooth Motion node, the previous, current, and next frames are
examined for a total of 3; with two Smooth Motion nodes, 5 frames are examined; and
with three Smooth Motion nodes, 7 frames are examined.
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