A method of formatting
digital data and a method of decoding the formatted
digital data. User selectable format parameters vary the dimensions and other attributes of spots and the cells containing those spots as well as other features which the formatting process formats into a pattern. A method of encoding the formatted
digital data using these format parameters allows for encoding a substrate optimally for any given printer or
scanner. One embodiment provides for markers to facilitate determination of
cell locations. In one embodiment the decoding process achieves a
pyramid gain of knowledge by locating a
landmark (801), which is located in a known position relative to a metasector (802), which contains information about the encoding process used to
encode the main body of data (803), which the decoding process
decodes to recover the original digital data. Further embodiments include
encryption, transmission by
facsimile, inclusion of human readable information, and automatic launches of computer files.