Patent ID: 8326041

Claim:
A computer implemented method of verifying recognition of magnetically encoded data encoded in a plurality of characters on a document, each of said characters magnetically and optically recognizable, said method comprising: optically imaging said plurality of characters; optically recognizing each of said imaged plurality of characters to form a corresponding optically recognized character datum; magnetically recognizing each of said plurality of characters to form a corresponding magnetically recognized character datum; for each of said plurality of characters determining a numerical quality of match between said optically recognized character datum and said magnetically recognized character datum representing a numerical probability of having optically recognized that character as said magnetically recognized character datum, determined for each of said plurality of characters using a tabulated numerical probability of optically recognizing that character as another character; calculating a cumulative quality of match representing a joint probability of having optically recognized each particular said character as said magnetically recognized character datum, for all of said plurality of characters, from said numerical quality of match for all of said plurality of characters; wherein said cumulative quality of match for said plurality of characters, is calculated by multiplying said numerical quality of match for each of said characters; and identifying an error if said cumulative quality of match fails to exceed a defined threshold.