A mask can look acceptable on individual stills while its boundary changes unnaturally between frames. Inspect the hair edge in motion over a simple contrasting background. If fine strands appear, vanish and reappear without corresponding source movement, diagnose temporal matte instability before regenerating the character. Keep the original footage and the mask pass separately so you can locate the responsible stage.
Isolate the edge from the new scene
Temporarily replace the receiving background with a flat diagnostic color in your external compositor. Compare the same interval with the original source. Busy scenery can conceal a unstable edge in a screenshot while making it distracting during normal playback.
Adobe describes Roto Brush and matte refinement. Use the supported propagation and refinement controls of the actual editor. A reviewed anchor frame is only a starting point; it does not validate the complete propagated span.
Find the first unstable frame
- Select a short interval containing the visible hair flicker.
- Watch it at normal speed, then step through the boundary changes.
- Compare source hair movement with the matte’s changing coverage.
- Correct the earliest failed propagation point and review the following span.
- Render a short test and inspect it at delivery size.
If the source itself is blurred or the hair disappears behind another person, full strand recovery may be unsupported. Prefer a plausible soft boundary to a sharp invented hairstyle, and document unavoidable approximations if the project requires faithful replacement.
Avoid broad fixes that erase identity
A larger feather can hide chatter but also soften the head into a visible cloud. Eroding the mask can remove the hairstyle’s silhouette. Judge the complete portrait as well as the edge, particularly around distinctive curls or loose strands that identify the character.
Why does the exported clip flicker more than the preview?
Preview resolution and caching can conceal a problem. Review a rendered test using the intended frame rate and dimensions. Confirm that the playback system itself is not dropping frames before changing the mask.
Should I regenerate the face to solve it?
Only if the character pass itself contains unstable hair or identity. If the defect appears during isolation or composition, fix that stage first. A new face generation introduces another variable without necessarily improving the boundary.
Sources and scope
This is an original Imagild Editorial workflow guide, assisted by AI and reviewed against the linked sources on October 12, 2026. External tool procedures do not imply that Imagild provides those tools or guarantees their results.