broll-core (shared library)

Single source of truth for the broll-* family so the base-layer skills produce interchangeable output and the avatar-PiP compositor lives in exactly one place (DRY). It is a library, not a user-facing skill — you never invoke it directly.

What's here (scripts/)

Who uses it

broll-web-capture ──────┐
broll-browser-recorder ─┤
broll-terminal ─────────┼─► broll-core  (geometry, ffmpeg, manifest, PiP compositor)
broll-demo-avatar ──────┘

How skills import it

Each consumer adds broll-core/scripts to sys.path (resolved relative to the skill, assuming the sibling .cursor/skills/<skill>/scripts/ layout) and then import _common as C / import pip_overlay as PIP. If broll-core is missing, the consumer fails fast with an install hint.

Setup

pip3 install -r .cursor/skills/broll-core/scripts/requirements.txt

ffmpeg + ffprobe must be on PATH. This library has no other runtime deps.

Conventions (keep these stable — other skills depend on them)

• Geometry: outputs use ASPECTS; 9:16 is 1080×1920 at 30fps, matching avatar-reel-composer.
• Output: clips are NNN_<slug>.mp4 (zero-padded, auto-incremented via next_index) and each run appends an entry to manifest.json ({"clips": [...]}), a drop-in for avatar-reel-composer (broll_source: "existing").
• Avatar PiP: by default (length="avatar") the avatar carries audio and drives length; the base loops to cover it. With length="base" the base drives length (a recorded demo is the hero) and the avatar freezes on its last frame once its narration ends. Either way the avatar clip should be a static, face-forward pip shot (avatar-camera-angles --move pip) lip-synced locked with p-video-avatar.