How to Cut an AI Dance Video to the Beat in Edit

Introduction

Every phrase generated cleanly. The kicks are right, the turn is right, the character is the same in every clip. You lay them end to end, drop the track on, and the whole thing is slightly wrong — each move lands a beat late, the turn ends before the bar does, and the energy leaks out between clips. Your instinct is to regenerate. Do not. Nothing about the clips is wrong; the cut is.

Dance video timing is an editing problem far more often than a generation problem, and it is cheaper to solve there. This guide shows how to cut an AI dance video to the beat in Edit: how to count the track, how to match each shot to its phrase, where to put the cut, and the few cases where a clip really does need to go back to the generator.

Count the track first

Before touching a clip, count the music. Most dance tracks phrase in eights: eight counts to a phrase, phrases grouped in fours. Write the phrase map down with timestamps:

• 0:00–0:04 — phrase 1, intro, no move
• 0:04–0:08 — phrase 2, kick-step ×2
• 0:08–0:12 — phrase 3, hop-turn
• and so on

Each phrase is one shot. If you generated the dance from a mannequin reference you already have this map; the shots were built from it. If you did not, make the map now, because every trim decision comes from it.

Rules for cutting to the beat

• Cut on the downbeat. Count one of each phrase is where the cut lands. Not the move; the cut.
• The move peaks after the cut, not on it. A kick that lands on count one reads as on time when the cut was on count one and the kick peaks a hair later. Cut early, let the move arrive.
• Trim, never stretch. A clip that is too short gets a different clip; a clip that is too long gets trimmed. Slowing a clip to fill a phrase reads as slow motion.
• Same trim logic in every shot. If shot 1 is cut with the character mid-prep, every shot is. Consistency of the cut is half of what makes it feel choreographed.
• Energy comes from the cut, not the clip. Shorter clips feel faster. If a section drags, trim harder before you generate anything.

For how much time a single shot gets in general, the duration and beat design guide covers the rule of thumb. This article is dance-specific: the count is the rule.

How to cut the dance in Edit, step by step

1. Add the track first. In Edit, put the BGM on the timeline before any clip so you are cutting to it, not to silence.
2. Mark the downbeats. Play the track and note each phrase start against the timeline. These are your cut points.
3. Place each shot at its phrase's downbeat. Shot 2 starts at 0:04, shot 3 at 0:08. Do not worry about the clip length yet.
4. Trim the head of each clip so the move begins just after the cut — usually the frame where the prep is done and the move starts. Cut the dead air before it.
5. Trim the tail to the next downbeat. Whatever the clip does after that, the next shot covers it.
6. Watch each cut in isolation. Does the move peak inside its phrase? If it peaks late, trim more from the head. If it peaks too early, the clip started mid-move; swap in a take with more prep, or accept a small gap covered by the next cut.
7. Watch the whole thing once at speed. Mark only the cuts that feel wrong. Fix those; leave the rest.
8. Regenerate only if a clip's move is shorter than its phrase. A two-count move in a four-count phrase cannot be trimmed into shape. Regenerate that phrase with the full move described, or split the phrase into two shots.

Example 1: A clip that runs long

Phrase 2, counts 1–8, 0:04–0:08. Generated clip: 6 seconds, kick-step ×2 completed by 3.5 seconds, then @Yuki idles.
Cut: head trimmed 0.4 s so the first kick begins just after the downbeat at 0:04; tail trimmed at 0:08 so the idle never shows. Result: two kicks inside the phrase, second kick peaking on count 5. Clip length on the timeline 4.0 s.

Example 2: A move that peaks late

Phrase 3, counts 1–8, 0:08–0:12. Generated clip: hop-turn, with @Yuki taking 1.2 seconds of prep before the hop.
Cut: head trimmed 1.0 s so the hop leaves the floor just after the downbeat at 0:08; the landing settles on count 5. Tail trimmed at 0:12. The prep is gone; the previous shot's tail covers the setup, and the cut lands on the downbeat. No regeneration needed.

Example 3: The one that needs a regeneration

Phrase 5, counts 1–8, 0:16–0:20. Generated clip: a single slow arm wave that finishes in 1.5 seconds, then @Yuki stands still.
Decision: the move is shorter than the phrase; no trim fixes a 1.5-second move in a 4-second slot. Regenerate the shot as "two arm waves, left then right, over four counts, from pose still wave-01 to wave-02," then cut it in with the same head trim as Shot 2.

The most common ways the cut breaks

• Cut on the move, not the downbeat. Everything feels late. Move the cut points to the count-one marks.
• Clips stretched to fit. Slow-motion feel. Trim instead; cover gaps with the next cut.
• Inconsistent head trims. One shot starts on the prep, the next on the move. Pick one and apply it everywhere.
• Track added last. Cuts landed on nothing. Put the BGM down first.
• Regenerating for timing. Five rerolls of a clip that only needed a trim. Cut first; regenerate only when the move is shorter than the phrase.

FAQ

Can I cut inside a phrase? Yes, on count five; a mid-phrase cut on the half works when a move has two halves. Avoid cutting on other counts; it reads as a mistake.

What if the track has no clear phrases? Count it in fours anyway and cut on the strongest hit in each four. Dance works on regularity; impose it if the track does not offer it.

Does the character voice or a lip-synced line change the cut? If there is a sung or spoken line, the line owns the cut: cut so the line starts on its beat, then fit the moves around it.

How short can a clip be? As short as a single count if the move reads. Fast sections are often one-count cuts of the peak pose; the cut supplies the energy.

Next step

Put the track on the Edit timeline and mark the downbeats before you place a single clip. Lay the shots at their phrase starts, trim heads so each move begins just after the cut, and watch once at speed. Open the project in ArcLoop, and only send back to the generator the phrase whose move is shorter than its slot.