Store 256GB on an A4 sheet - Files such as text, images, sounds and video clips are encoded in "rainbow format" as coloured circles, triangles, squares and so on, and printed as dense graphics on paper at a density of 2.7GB per square inch. The paper can then be read through a specially developed scanner and the contents decoded into their original digital format and viewed or played. The encoding and decoding processes have not been revealed.
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