Rotoscoping

Rotoscoping is one of the most labor-intensive but essential techniques in visual effects. When an element in a shot needs to be isolated — a person separated from their background, an object removed or replaced, an effect applied to only a specific area — and no automated method (like chroma keying) can achieve the isolation cleanly, a rotoscope artist manually draws a detailed outline around the element, adjusting the shape frame by frame as the subject moves.

Modern rotoscoping tools have evolved significantly from purely manual tracing. Software now offers intelligent edge detection, motion estimation between keyframes, and AI-powered masking that can dramatically reduce the manual work required. However, complex scenarios — detailed hair edges, transparent objects, fast motion with motion blur — still require skilled manual refinement. A rotoscope artist must understand how edges behave, how motion blur affects boundaries, and how to create mattes that composite naturally.

Rotoscoping enables visual effects that would otherwise require green screen shoots. Need to place a person in a different environment but the original footage was not shot on green screen? Rotoscoping can isolate them. Need to change the color of a specific object in a shot? Rotoscoping creates the mask. While it represents a significant post-production investment in terms of time, rotoscoping provides unlimited creative flexibility after the fact, making it invaluable when the desired effect was not planned during production.