B-roll Overlay

In plain words

Cover the narration with related scenes so the words are shown as pictures.

When to use it

Explainer ads, review-style short-form, and app feature explanations.

Example videos

▶

▶

In AI video, like this

Generate one B-roll clip for each narration sentence. Lay the audio track first, then put the B-roll on top and match the start of each spoken line to its picture.

One-click prompt

Cover the narrator clip with b-roll from second 2 to second 5 while the narration keeps playing: ffmpeg -i talk.mp4 -i broll.mp4 -filter_complex "[1:v]scale=1080:1920,setpts=PTS-STARTPTS+2/TB[b];[0:v][b]overlay=enable='between(t,2,5)'[v]" -map "[v]" -map 0:a -c:a copy out.mp4. Make one b-roll clip per narration sentence.

See it in real films and ads

Inside The Edit — How to Edit B-Roll Like a Pro

AI-made examples

CREATE with JAY — 5 Ways to Make AI B-Roll for Shorts

Recommended for scenes like these

Techniques that pair well