Mobile demo film

Use this skill to edit a new demo from real app recordings. The bundled renderer produces silent video with configurable dimensions, frame rate, framing, and fades. Defaults are 1080x1920 at 30fps, with a phone frame on a warm paper backdrop. A useful default is one feature in 20 to 40 seconds; adapt the story and pacing to the request.

Prerequisites

Use Python 3.10+, Pillow 10.1+, and ffmpeg (including ffprobe and libx264). Recording with mobile-demo-record needs macOS; editing existing footage does not. Font discovery tries macOS system fonts, then Linux DejaVu fonts, then Pillow’s fallback. Specify font files for consistent typography across machines. Install Pillow in a scratch virtual environment:

python3 -m venv <scratch>/film-venv
<scratch>/film-venv/bin/pip install "Pillow>=10.1"