1. A method comprising: identifying a plurality of markings, each of the plurality of markings corresponding to one of a sequence of positions; and encoding the plurality of markings, via a processor, using: a first identifier representing a current position of the sequence of positions; and a plurality of additional identifiers, each of the plurality of additional identifier representing a previous one of the positions of the sequence, such that the current position can be determined based on the first identifier in combination with the additional identifiers.