1. A method of imaging a coding pattern disposed on a surface of a substrate, said method comprising the steps of: (a) capturing an image of a portion of said coding pattern, said coding pattern comprising: a plurality of target elements defining a target grid, said target grid comprising a plurality of cells, wherein neighboring cells share target elements; a plurality of data elements contained in each cell; and a plurality of tags, each tag being defined by a plurality of contiguous cells, each tag comprising respective local tag data encoded by a respective set of said data elements, wherein said data elements encode data values by multi-pulse position modulation; and (b) low-pass filtering said captured image so as to obscure said data elements and preserve said target elements.