J-cut

Full motion specification

How the movement works

To build anticipation for the next scene, or to make a change of scene or speaker feel natural.

1. 01Join: the picture is a straight cut; only the audio switches to the next scene (B) before the picture does. The offset is 20% of the timeline (0.72 s)
2. 02Playhead: moves left to right at constant speed over 3.6 s (0.4 s to 4.0 s); audio switches at 35% (about 1.66 s), picture at 55% (about 2.38 s)
3. 03In the offset section (35–55%) the picture is still A while the audio is already B; the section is marked with a pale blue band and two blue dashed lines
4. 04Layout: the top 134 px is the picture (fixed camera, subjects do not move); the bottom 74 px holds two timeline rows, video and audio (A grey, B pale blue, waveform on the audio row)
5. 05Labels: "映像A / 映像B" (video A / B) at bottom left of the picture; the audio now playing at bottom right ("♪ Aの音" grey → "♪ Bの音" blue)
6. 06Return: cross-fade back to the start over the last 0.5 s (one pass = 4.7 s)