Currency is validated by comparing identifying information extracted from
the currency, such as a serial number associated with the currency, to
identifying information in a list corresponding to invalid currency, such
as counterfeit currency. If the extracted identifying information matches
identifying information on the list, the currency is deemed invalid. A
photograph or thumbprint image can be obtained by a person using the
invalid currency to help in later identification of that individual.
Optical character recognition techniques can be used to extract the
identifying information.