Ghost Font: A motion-based font humans can read, but GPT-Sol 5.6 Ultra and Claude Fable can't decode

Ghost Font: A font that humans can read but AI cannot

Mixfont built Ghost Font, an experimental font that hides text inside moving video. Humans read the letters by tracking motion; a still frame shows only noise. When tested, GPT-Sol 5.6 Ultra and Claude Fable both fell for a planted decoy message and missed the real moving text. ChatGPT 5.5 Pro hallucinated a nonexistent message after 19 minutes of analysis. The trick relies on motion perception plus a decoy layer, not encryption. The post says the video-generation code will be open-sourced later, and the author is considering CAPTCHA or visual-perception benchmarks as use cases. Current limit is 36 characters per message; videos can be downloaded and shared.

Why it matters: Fresh concept with concrete model test results and strong conversation value for AI practitioners—hits all three HKR axes. Score held at 72 because it's more a clever hack than an industry event, and the post doesn't disclose full testing methodology.