Split Animated Short — user talking head (taller live band)

HARD RULE (Kevin 2026-09-03): Final video is 1080×1920. Never 720×1280. Never scale the user's talking-head down to 704×640. Their clip is already 1080p. Instagram/TikTok/YouTube Shorts display at 1080×1920; a 720p master gets upscaled and looks like mud. If ffprobe on renders/final.mp4 is not 1080x1920, delete it and start over. Do not publish 720p.

Same flagship format as split-animated-short, except the bottom band is the clip the user hands you, not a HeyGen talking-photo. The clip's audio is the master timeline. Animations are authored per script — zero pixels from any reference reel except its words, if one is given.

Live talking-head footage needs more band height than the HeyGen 45% lock so hats/hair aren't clipped (Kevin 2026-09-01). Default band is 1056×960 at y=936 on the 1080×1920 canvas (caption baseline rests ON the accent line at y=BAND_Y-5, letters fully above the head; Kevin 2026-09-18/19). Round all four corners of the band mask — never BAND_H+60 (that square-cuts the bottom flush to the canvas). ~24px of canvas stays under the card.