is present referring again to fig1 the program would identify the presence of conductive material on pixel a 4 the examination of the surrounding pixels would depend on the search routine implemented by the computer program in this example since the program began the exhaustive search from the top left a 1 pixel the computer program would set the pixel element containing conductive material equal to the top left element of the three by three contact pad this is because the program has already determined that all pixels above and to the left of the current position do not satisfy the three by three criteria of conductive units required to form a pad thus it is not necessary to reexamine the pixels already visited once this step is performed the program checks for the presence of conductive material on the other eight pixels comprising the contact pad this may be accomplished in a number of ways the computer program may then check the next two pixels in the row a 5 and a 6 for the presence of conductive material in fig1 a 5 contains conductive material but pixel a 6 does not once it was determined that pixel a 6 does not contain conductive material the program would return to pixel a 4 and having determined that pixel a 4 is not the upper left hand corner of a contact pad would continue to pixel a 5 and continue the search for a contact pad in fig1 this search would.