Like Subscribe Overlay

like-subscribe-overlay

Drops a hook-grabbing branded call to action into the short. A JS-driven animation plays in the lower third for dur seconds starting at pos fraction of the clip (default 0.15), with the start clamped so the whole CTA lands inside the first third of the clip — where retention is highest — while staying clear of the ~2.5s title card: a Carbon Black pill pops in carrying the channel gem avatar (sapphire-ringed, glow breathing) and the @C0BALT_CUT handle (Impact, Platinum, sapphire slashed zero) → cursor enters → clicks SUBSCRIBE (red → dark, scale punch, expanding ring) → bell rings → cursor glides left to the thumbs-up → clicks LIKE (thumb fills Sapphire Glow, scale punch, expanding ring) → holds the final state.

The animation is authored in plain HTML+CSS+JS (cta.html) and pre-rendered once into a transparent ProRes 4444 .mov asset (assets/cta.mov). Runtime just composites that asset. The avatar image is assets/channel.png (square crop of the channel gem); replace it and re-run build-cta.sh to rebrand.

Invoke

.claude/skills/like-subscribe-overlay/like-subscribe-overlay.sh <input> <out> [dur=4.0] [pos=0.15]

• input: finished short (any aspect ratio; designed for 1080x1920)
• out: output mp4
• dur: total CTA duration in seconds (clamped to clip length, default 4.0)
• pos: fraction of the clip at which the CTA starts (default 0.15; clamped so the CTA ends inside the first third, starts after the ~2.5s title card, and never spills past the end of the clip — in that priority order)

Output

mp4, same dimensions and duration as the input, video re-encoded (libx264 veryfast crf18), audio re-encoded to AAC 192k. Prints the output path to stdout. Idempotent: a <out>.lsmeta sidecar records the signature (dur|pos|asset-version); a cache hit requires out newer than input and a matching signature.

Brand

Colors from brand/BRAND.md: pill in Carbon Black #101418 with a Sapphire Glow #2E6BFF edge, handle in Platinum #E8ECF1 Impact with the slashed zero in Sapphire Glow (same visual language as the watermark renderer), liked thumb fills Sapphire Glow. The SUBSCRIBE button stays YouTube red pre-click for instant recognition.

Where in the pipeline

Runs after loudnorm and before bg-music / save-local. The overlay lands inside the first third of the clip (after the title card), so it composites over whatever is on screen early in the story (captions burn beneath it for those 4 seconds — intended).

How

1. build-cta.sh (one-time, or whenever cta.html / assets/channel.png changes): build-cta.js steps cta.html's deterministic window.setT(t) frame-by-frame in headless Chromium (Playwright, omitBackground) and ffmpeg-encodes the transparent PNGs to assets/cta.mov (ProRes 4444).
2. like-subscribe-overlay.sh time-stretches the asset to dur (setpts), pins it to the lower third, and enables it for [start, start+dur] where start = min(pos * clip_duration, clip_duration/3 - dur) floored at 3.0s (title-card clearance). The CTA overlays SILENTLY — the clip's source audio passes straight through (-map 0:a, no mix). The old bell-ding SFX (make_sfx.py) is retired; make_sfx.py is unused.