caption-retime-and-render

name	caption-retime-and-render
description	Use when captions must be regenerated or retimed after text-based cuts, filler deletion, silence removal, MV lyrics timing, or TVC disclaimer timing.

Caption Retime and Render

Use this skill after plans/cuts.json or lyrics alignment exists.

Inputs:

• transcript/words.json or analysis/lyrics/alignment.json
• plans/cuts.json
• sourceToOutputMap
• caption wordRefs

Outputs:

• captions/captions.json
• projections/timelines/<asset-id>.caption.timeline.yaml
• projections/timelines/<asset-id>.caption-overlay.timeline.yaml
• projections/timelines/<asset-id>.caption-overlay.timeline-manifest.json
• projections/caption-burn/<asset-id>.caption-burn.json
• optional .srt, .vtt, .ass
• optional rendered overlay asset

Current local caption sidecar export:

clash production export-captions \
  --timeline projections/timelines/<asset-id>.caption.timeline.yaml \
  --format srt \
  --out exports/captions/<asset-id>.srt \
  --json

clash production export-captions \
  --timeline projections/timelines/<asset-id>.caption.timeline.yaml \
  --format vtt \
  --out exports/captions/<asset-id>.vtt \
  --json

clash production export-captions \
  --timeline projections/timelines/<asset-id>.caption.timeline.yaml \
  --format ass \
  --out exports/captions/<asset-id>.ass \
  --json

clash production project-caption-overlay \
  --timeline projections/timelines/<asset-id>.caption.timeline.yaml \
  --out projections/timelines/<asset-id>.caption-overlay.timeline.yaml \
  --json

clash production export-caption-burn \
  --timeline projections/timelines/<asset-id>.caption.timeline.yaml \
  --source-asset <source-video-asset-id> \
  --output-asset <asset-id>-caption-burn \
  --out assets/video/<asset-id>-caption-burn.mp4 \
  --assets assets/manifest.json \
  --json

This consumes structured caption timeline items and writes a clash.caption.export manifest next to the sidecar file. The overlay projection command writes a clash.caption.timeline-overlay manifest with Remotion preview renderer metadata and an explicit clash timeline apply CAS boundary. The caption burn command writes an ASS sidecar, an FFmpeg plan, a copy-on-write clash.caption.burn-in-export package, and a derived asset manifest entry; add --render only after review to render the burned-in video.

Rules:

• Captions use output timestamps, not original source timestamps.
• Deleted words disappear from captions unless subtitle-only mode is used.
• Every cue should carry wordIds, sourceStartFrame, and sourceEndFrame.
• Timeline caption items should include wordRefs and sourceToOutputMap; plain text clips are text overlays, not a complete字幕 system.
• Disclaimers in ads must satisfy minimum visible duration and safe area.