| name | jump-cut |
| description | Manufacture "multi-cam" hard cuts on static talking-head stretches by alternating a base framing with tighter punch-in reframings of the SAME speaker, each cut snapped to a word start so it lands on speech. Deterministic, no Claude. Timeline-preserving — audio is copied untouched and total duration is identical, so every downstream timestamp (captions, b-roll windows) stays valid. Runs on the 1080x1920 vertical clip AFTER fill-vertical and BEFORE zoom-punch/broll/burn-subtitles, so cutaways override their own windows and captions burn on top. The visual-change-density lever for sources where b-roll stays sparse. |
| allowed-tools | Bash |
| user-invocable | true |
jump-cut
Single-camera podcast footage reads as one long static crop between cutaways.
Top short-form editors break that up with frequent hard cuts between framings of
the same speaker — a fake "multi-cam" rhythm that keeps the frame changing even
with no new footage. This skill manufactures that churn deterministically.
Invoke
.claude/skills/jump-cut/jump-cut.sh <in.mp4> <transcript.json> <out.mp4> [seg_secs=3.2]
in.mp4: the 1080x1920 vertical clip (post fill-vertical)transcript.json: the clip-local word-timed transcript (cuts snap to word starts)seg_secs: target segment length / cut rhythm (default 3.2s)
How it works
plan.py tiles [0, dur] into segments at ~seg_secs spacing, each boundary
snapped to the nearest word start within 0.7s so the cut lands ON speech.- Segments alternate base (full frame, unchanged) and punch (a centered
~1.11–1.16x reframe biased to the upper third). The cold-open lead (2.6s, the
title) and the tail (1.5s, the landing) stay base for a stable open/close.
- One ffmpeg pass:
split → per-segment trim+crop/scale → concat. Video
is concatenated; audio is mapped straight from the source with -c:a copy,
so duration and every downstream timestamp are preserved exactly.
Placement rules
- count = clamp by
seg_secs rhythm, capped at JUMP_CUT_MAX (default 8) cuts
- clips shorter than
JUMP_CUT_MIN (default 13s) → passthrough (no churn)
- first 2.6s (cold-open title) and last 1.5s excluded
- min 1.6s between cuts after snapping (never seasick)
Pipeline order
fill-vertical → jump-cut → zoom-punch → chunk-captions → broll-pick
→ broll-composite → burn-subtitles → …
It must touch only the clean vertical: b-roll cutaways replace the full frame in
their windows (overriding the reframe underneath) and captions burn on top, so
neither warps. Non-fatal (any failure → passthrough), idempotent (.jcmeta
mtime+param signature), JUMP_CUT=0 disables.
Env
JUMP_CUT — 0 disables (passthrough). Default on.JUMP_CUT_SEG — cut rhythm in seconds (default 3.2; also positional arg 4).JUMP_CUT_MAX — max reframe cuts per clip (default 8).JUMP_CUT_MIN — min clip duration to activate (default 13.0s).JUMP_CUT_LEAD / JUMP_CUT_TAIL — stable open/close reserve (default 2.6 / 1.5).
