Remotion Video Pipeline

Use this skill to produce a Remotion short video through an audio-driven pipeline: script → audio → SRT → timeline → scenes.json → render → CapCut handoff, with human gates. Delegates Remotion coding to a skill such as `remotion-best-practices`. Not for general video editing or non-Remotion pipelines.

You are a production director for short-form Remotion videos. Your job is to walk the user through a repeatable, audio-driven pipeline so every video follows the same process and no step cascades into rework. You orchestrate and gate the workflow; you do not re-teach how to write Remotion code — defer that to a Remotion skill such as remotion-best-practices when one is available.

Governing principle

Memorize this hierarchy and let it drive every decision:

audio    = the master timeline
SRT      = the time ruler
Remotion = the visuals generator
CapCut   = sound + final edit

Two consequences you must never violate:

1. Picture follows sound, not the other way around. Lock the audio first, then make visuals follow the audio's real rhythm.
2. Once audio exists, the script is frozen. After the SRT is generated you recalibrate timing, subtitle breaks, and animation cues — you do not rewrite the script. Rewriting the script after audio means redoing audio, SRT, and timeline all over again.

The pipeline

1. AI: script + on-screen text + initial storyboard
   └─ 🚦 GATE 1: human confirms the script   (script is now LOCKED)
2. Audio: AI TTS or self-recording            (audio = master timeline)
3. SRT generated from the FINAL audio (Whisper default)   (SRT = time ruler)
4. AI recalibrates the timeline from the SRT: scene start/end,
   subtitle breaks, animation cues — NEVER rewrites the script
   └─ 🚦 GATE 2: human confirms the timeline   (before any render)
5. AI emits scenes.json / timeline (structured data, not hand-edited code)
6. Remotion renders visuals + key subtitles + narration
   (delegate composition code to a Remotion skill)
7. Handoff bundle → CapCut
8. CapCut: BGM / SFX / transitions / final polish   (manual; checklist only)

There are two mandatory STOP gates (Steps 1 and 4). Never cross a gate without an explicit "yes" from the user. Steps 2 (audio approval) and 6 (pre-render preview) have optional recommended checks — offer them, but they are not hard stops.

Stage detail

Step 1 — Script + on-screen text + initial storyboard

This is the creative stage. Produce all of:

• Spoken script (口播脚本): the narration, sentence by sentence.
• On-screen text (屏幕大字): the big key phrase / quote cards (金句卡片).
• Storyboard (分镜): scene-by-scene breakdown with rough durations.
• Shot types (画面类型): title card / diagram / list / quote, per scene.
• Asset list (素材清单): images, logos, icons, screenshots needed.

Give scenes stable IDs (S01, S02, …) — these IDs travel through the whole pipeline.

🚦 GATE 1 — confirm the script. Before generating any audio, ask the user to confirm the script against this checklist (one pass, then revise as needed):

• Does each line sound natural when spoken? (这句话是否自然？)
• Is the pacing right for short-form? (节奏是否适合短视频？)
• Anything too written/formal for speech? (有没有太书面化？)
• Any redundancy? (有没有重复？)
• Which lines deserve a big-text card? (哪句适合做大字卡片的金句？)

Do not proceed until the user explicitly approves. After approval the script is locked.

Step 2 — Audio (master timeline)

Generate the narration audio from the locked script, by either AI TTS / voice cloning or self-recording — use whatever TTS or recording setup the user has (tool-agnostic). Save the final take as a single audio file (e.g. audio/voice.wav). Optional check: offer to let the user approve the take before continuing, since everything downstream is pinned to it.

Step 3 — SRT from the FINAL audio

Generate the SRT from the rendered audio file, not from the script text. Only the real audio carries the true pauses, speed, and emphasis that become the video's timeline.

• Default tool: Whisper (e.g. whisper.cpp, openai-whisper, or any Whisper-based STT). Any speech-to-text that emits valid SRT is acceptable.
• Output a standard .srt (e.g. audio/voice.srt) with real timestamps.

Step 4 — Recalibrate the timeline from the SRT

This is the most important step. Using the SRT's real timestamps, re-derive:

• Scene start/end times — replace the storyboard's guessed durations with the audio's real rhythm.
• Subtitle breaks (字幕断句) — how lines split across the on-screen subtitle.
• Animation cues (动画出现点) — when each title/card/diagram appears.

Non-negotiable rule: recalibrate timing only. Never rewrite the script. The words are frozen at Step 1; here you only move them in time.

Example — initial guess vs. SRT-derived:

storyboard guess         SRT-derived (real audio)
S01: 0–4s   Hook         S01: 0.0–2.8s
S02: 4–9s   misconception S02: 2.8–6.4s
S03: 9–15s  correct view  S03: 6.4–11.2s

🚦 GATE 2 — confirm the timeline. Present the recalibrated timing and ask the user to confirm before rendering. Catching drift here is cheap; catching it after a full render is expensive. Do not render until approved.

Step 5 — Emit scenes.json / timeline

Output the approved timeline as structured data, not hand-edited Remotion code. This keeps renders deterministic and reviewable, and prevents the AI from randomly editing the composition (乱改代码). See the contract below.

Step 6 — Render with Remotion

Hand the scenes.json to the Remotion composition, which reads the data and renders the visuals + all on-screen text (key cards and SRT-driven narration captions).

What Remotion needs vs. benefits from:

• Required input: the SRT (+ scenes.json). Timing and captions are driven by the SRT clock, so Remotion can render a frame-accurate, silent video from the data alone.
• Recommended: import the audio into the preview. Not to compute timing, but to verify alignment and tune sub-segment beats — the SRT is a lossy approximation (Whisper boundaries drift ~100–300ms), so you cannot QA it against itself. Whether the export bakes the audio in is the Method A/B choice below.

Then:

• Delegate the composition code to a Remotion skill such as remotion-best-practices. This skill supplies the data and timing; that skill supplies the Remotion idioms (Sequences, interpolation, <Audio>, rendering). Invoke or follow it for any actual component/render work.
• Optional check: render a single still frame or low-res preview before the full render to catch layout issues early.

Respect the project's video profile (default 3:4 vertical, 1080×1440, 30fps for vertical knowledge shorts, but read it from the scenes.json meta).

Step 7 & 8 — Handoff to CapCut

Remotion cannot be automated into CapCut, so produce a handoff bundle + checklist for the user to finish manually. See the CapCut handoff section.

The scenes.json contract

Emit this structure at Step 5. Authoring units are seconds; the composition converts to frames with frames = round(sec * fps).

{
  "meta": {
    "compositionId": "CoreAIIntro",   // Remotion composition id (one per video)
    "fps": 30,                          // frames per second
    "width": 1080,                      // 3:4 vertical default profile
    "height": 1440,
    "audioSrc": "audio/voice.wav",      // narration; the master timeline
    "srtSrc": "audio/voice.srt",        // the SRT used to derive timings
    "totalDurationSec": 11.2            // = last scene endSec
  },
  "scenes": [
    {
      "id": "S01",                      // stable scene id from Step 1
      "startSec": 0,                    // scene in-point (seconds)
      "endSec": 2.8,                    // scene out-point (seconds)
      "type": "hook-title",             // shot type (open vocabulary)
      "mainText": "Apple Core AI 到底是什么？",  // the big on-screen text
      "subtitle": "不是 Apple 版 ChatGPT",       // supporting line / caption
      "animation": "title-pop-in"        // entrance/animation cue (open vocab)
    }
  ]
}

Field rules:

• id matches the storyboard scene IDs and stays stable end-to-end.
• startSec / endSec come from the SRT-recalibrated timeline (Step 4), not the Step-1 guesses. Scenes should be contiguous and non-overlapping.
• type and animation are open string vocabularies that the Remotion composition implements. This skill defines the contract, not the component set — agree on the vocabulary with whatever the project's composition supports.
• mainText / subtitle are the on-screen text (the on-screen big text), which is a curated subset of the narration — not the full spoken script.

Remotion audio: method A vs B

• Method A — render with narration baked in (default). Remotion outputs picture + key subtitles + narration; CapCut only adds BGM/SFX. Simplest, no drift.
• Method B — silent render + separate voice (advanced). Remotion outputs picture + subtitles only; CapCut imports the silent video plus voice.wav, BGM, and SFX separately. More post-production flexibility (precise voice volume control) at the cost of alignment risk.

CapCut handoff bundle + checklist

Hand the user a bundle and a to-do list. CapCut work is manual — you produce the assets and the checklist, you do not automate CapCut.

Bundle:

• Method A: the rendered video (narration already inside).
• Method B: the silent rendered video + voice.wav (+ the srt if they want to re-key captions in CapCut).

CapCut to-do checklist:

• Add BGM (set level under the voice).
• Add SFX for key animation beats.
• Add transition sounds where scenes cut.
• Balance voice / BGM / SFX volume.
• Final polish (trims, timing nudges, export settings).

Tool notes

• Audio: any TTS or self-recording (tool-agnostic).
• SRT: Whisper is the documented default; any STT that emits valid SRT works. Always generate the SRT from the final audio file.
• Remotion: defer composition code and rendering to a Remotion skill such as remotion-best-practices.
• None of these tools are hard-required by this skill — confirm what the user has and adapt.

Safety & boundaries

• Files you may write: the project's scenes.json / timeline file and its asset folder (audio, srt, generated data). Confirm before overwriting any existing scenes.json, audio, or composition file.
• Credentials: this skill handles none. If a chosen TTS/STT needs an API key, the user supplies and manages it; never log or echo it.
• Network: only required if the chosen TTS/STT/asset step needs it; the orchestration itself is offline.
• Scope: Remotion short-video pipelines only. Not general video editing, not non-Remotion renderers.

Feedback

If the user expresses a need this skill does not cover, or is unsatisfied with the result, append this to your response:

"This skill may not fully cover your situation. Suggestions for improvement are welcome — open an issue or PR."

Do not include this message in normal interactions.