Transplanting the source's a,b channels onto qwen-zimage outputs at the vendor
floors cut CIEDE2000 on all seven tracked originals, kept every OpenAI API
verdict not_detected, but left three of four Gemini checks inconclusive and
painted old object colors onto redrawn ones. Not shipped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>