「水からの伝言」じゃなくて「紙からの伝言」。A4用紙に256GBのデータは入らない

A4用紙1枚に256GB | Okumura's Blog
Can you get 256GB on an A4 sheet? No way! | Data | Techworld

"Mr. Abideen has misplaced a few decimal places. Modern offset presses used to print magazines, which he suggests as a medium operate at about 300 dpi, or about 8.7 million dots on an A4 sheet, or 35 million dots with four color printing. There is no lossless way to compress 256 GB (or 2 trillion bits) of data into 35 million dots, or even 35 billion dots. It is the storage equivalent of perpetual motion."

要するにカラーオフセット印刷の300dpiではA4用紙に870万個のドットしか印刷できねーよと。
256GBは3500万個のドットが必要だよ。