Optical flow

An estimate of how every pixel moves from one frame to the next. It is the basis of synthesised slow motion, matte propagation and some kinds of tracking.

In Premation

Pixel Motion frame blending uses it to build in-between frames when footage is slowed, and the Roto Brush uses it to carry a matte through a clip.

Read the docs: Speed ramps

Related terms

• Frame blending
• Speed ramp
• Rotoscoping