The Decoder found forced_backdrop judged coverage from declared size alone.
pbafc.prm declares 844x600 at alpha ff and draws ~17x18 px at 2%x3% scale --
a rule reading declared size would call it screen-covering.
scale_at interpolates on the same ramp as the fade, and coverage is folded into
the opaque-instant test: an instant counts only where the element is BOTH alpha
255 and covering. The previous code tested the two halves at different times.
The size prefilter deliberately no longer rejects, since an element scaled above
100 could cover from a smaller declared size.
No verdict moves: 6 forced before and after, 16 screens validate, oracle figures
identical to the digit. Nothing in GP_TITLE has a non-100 scale on any keyframe.
It is in because the data that would break it exists, not because it failed.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF
06115af659