| name | pil-video-overlays |
| description | Use when video-use needs deterministic lightweight overlays made from Pillow/PIL images, PNG sequences, simple text cards, counters, progress bars, or reveal frames. |
PIL Video Overlays
Use this skill only as a child workflow of video-use. It creates deterministic PNG-sequence or alpha WebM overlays using Pillow/PIL plus ffmpeg.
Contract
- Work under
edit/animations/slot_<id>/.
- Output
edit/animations/slot_<id>/render.webm with alpha when possible.
- PNG frames should live under
edit/animations/slot_<id>/frames/.
- Do not edit source footage or final videos directly.
- Return an
edl.json overlays[] item with file, start, end, x, and y.
{"file":"animations/slot_01/render.webm","start":2.0,"end":5.0,"x":0,"y":0}
Use For
- Simple cards, counters, progress bars, badges, step reveals, static diagrams with light motion.
- Lowest-dependency fallback when HyperFrames, Remotion, or Manim are unavailable.
Workflow
- Create
edit/animations/slot_<id>/frames/.
- Generate RGBA PNG frames with Pillow/PIL at the target dimensions and fps.
- Encode frames to
render.webm with alpha using ffmpeg VP8/VP9 settings.
- Verify alpha, dimensions, duration, frame count, and safe zones.
- Save generation parameters and frame counts in
manifest.json.
Rules
- Use Source Han Sans / 思源黑体 or a documented fallback for Chinese text.
- Keep text large enough for mobile and avoid subtitle safe zones.
- Prefer deterministic frame generation over ad hoc manual edits.
video-use applies subtitles LAST, after this overlay is composited.
