video-analyserlisted
Install: claude install-skill mthines/agent-skills
# Video Analyser Skill
Analyse a video file to extract bugs, errors, UI state, and reproduction steps.
The pipeline uses `ffmpeg` for frame extraction, optional `tesseract` OCR for text, and optional `whisper` for audio narration.
The default path (8 keyframes at 768 px) is the Pareto-optimal setting for screen recordings: best quality-per-token on the legibility curve.
By default the selected frames are packed into a single tiled **contact sheet** and sent to the analysis prompt as one image.
This is cheaper on vision tokens and gives a temporal overview at a glance.
An opt-in **split** mode keeps the legacy behaviour of one full-resolution image block per frame — use it when small UI text must be read (see [Frame Delivery Mode](#frame-delivery-mode)).
## Prerequisites
### Required tools
| Tool | Check | If missing |
|---|---|---|
| `ffmpeg` | `which ffmpeg` | Print: `ffmpeg is required. Install with: brew install ffmpeg` (macOS) or `apt install ffmpeg` (Linux). Then exit. |
| `ffprobe` | `which ffprobe` | Print: `ffprobe is required. It ships with ffmpeg — reinstall ffmpeg`. Then exit. |
### Optional tools (silent degradation)
| Tool | If present | If absent |
|---|---|---|
| `tesseract` | Enable OCR mode for text-heavy frames | Skip silently; use vision-only mode |
| `whisper` | Enable audio transcription when user mentions narration or voiceover | Skip audio step silently |
Run tool detection before any other step.
```bash
which ffmpeg || { echo "ffmpeg is requi