Patent ID: 8607331

Claim:
A Completely Automated Public Turing Test to tell Computers and Humans Apart (CAPTCHA) image authentication method, comprising the steps of: collecting a plurality of first objects; defining a plurality of variables so as to be used as basis for classifying and dividing the plurality of first objects into M groups accordingly while allowing each group in the M groups to correspond to at least one variable selected from the plurality of variables; selecting one or more groups from the M groups while further grading and dividing the first objects in the selected one or more groups into subgroups of N grades based upon a standard unit of the variable corresponding to the selected one or more groups; sorting and storing the subgroups of N grades for each of the one of more groups; selecting a plurality of authentication objects from the subgroups of N grades for each of the one of more groups to be used in an authentication process; defining a selection criteria for each of the one of more groups based on the plurality of variables corresponding to each group; displaying the selection criteria and the plurality of authentication objects for each of the one of more groups on a display unit; requesting a user to sort the plurality of authentication objects for each of the one of more groups according to the selection criteria; and determining whether the plurality of authentication objects are sorted correctly for each of the one of more groups, and if so, the authentication process is determined to have passed, else selecting a new set of authentication objects for a future authentication process and the authentication process is determined to have failed.