Method and apparatus for authenticating handwritten signature based on multiple authentication algorithms

A method for authenticating a handwritten signature, the method comprising:

• receiving, at a characteristic extraction step, the handwritten signature to be authenticated, and extracting a plurality of pieces of signature behavioral characteristic information;
• applying, at a first analysis step, all the extracted plurality of the pieces of the signature behavioral characteristic information to each of a first signature authentication algorithm and a second signature authentication algorithm that perform handwritten signature authentication with different techniques, and generating a first analysis result and a second analysis result by analyzing a degree of matching between the received handwritten signature and a registered handwritten signature;
• determining, at an adjustment direction determination step, whether to perform either adjustment of a false acceptance rate or adjustment of a false rejection rate, by comparing each of the first analysis result and the second analysis result to each preset first analysis threshold value:
• extracting, at a second analysis step, the signature behavioral characteristic information sensitive to false-acceptance verification among the plurality of the pieces of the signature behavioral characteristic information when it is determined to perform adjustment of the false acceptance rate, and generating a third analysis result by analyzing the degree of matching between the received handwritten signature and the registered handwritten signature on the basis of the extracted signature behavioral characteristic information sensitive to false-acceptance verification;
• extracting, at a third analysis step, the signature behavioral characteristic information sensitive to false-rejection verification among the plurality of the pieces of the signature behavioral characteristic information when it is determined to perform adjustment of the false rejection rate, and generating a fourth analysis result by analyzing the degree of matching between the received handwritten signature and the registered handwritten signature on the basis of the extracted signature behavioral characteristic information sensitive to false-rejection verification;
• and
• determining, at a handwritten signature authentication step, whether authentication of the received handwritten signature succeeds, by comparing one or more of the analysis results of the first to the third analysis step to the first analysis threshold values and preset second analysis threshold values,
• wherein the third analysis result and the fourth analysis result are obtained by an analysis based on the second signature authentication algorithm, and
• at the determining of whether authentication succeeds, whether authentication succeeds is determined by comparing the first analysis result and the second analysis result of the first analysis step to the first analysis threshold values, and by comparing the first analysis result, the third analysis result, and the fourth analysis result to a first threshold value (ρ) among the first analysis threshold values and the second analysis threshold values.

An apparatus for authenticating a handwritten signature, the apparatus comprising:

• a handwritten signature input part configured to extract signature behavioral characteristic information from handwritten signature data of the handwritten signature that a user is writing by hand, and output the signature behavioral characteristic information;
• a storage part configured to store therein a first signature authentication algorithm and a second signature authentication algorithm using different handwritten signature authentication techniques, and store therein first analysis threshold values and second analysis threshold values for determining authentication for the first signature authentication algorithm and determining authentication for the second signature authentication algorithm;
• and
• a controller configured to:
• apply the signature behavioral characteristic information for analysis to each of the first signature authentication algorithm and the second signature authentication algorithm when the signature behavioral characteristic information is obtained;
• obtain a first analysis result analyzed by the first signature authentication algorithm and a second analysis result analyzed by the second signature authentication algorithm;
• determine an adjustment direction to determine whether to perform either adjustment of a false acceptance rate or adjustment of a false rejection rate, by comparing the obtained first analysis result and the obtained second analysis result to the first analysis threshold values;
• obtain a third analysis result and a fourth analysis result by extracting only the signature behavioral characteristic information sensitive according to the determined adjustment direction among all pieces of the signature behavioral characteristic information, and by applying the extracted signature behavioral characteristic information sensitive according to the determined adjustment direction to the second signature authentication algorithm;
• and determine whether authentication of the handwritten signature succeeds, by comparing the first analysis result, the third analysis result, and the fourth analysis result to a first threshold value (ρ) among the first analysis threshold values and the second analysis threshold values preset,
• wherein the controller comprises a handwritten signature authentication module,
• wherein the handwritten signature authentication module comprises:
• a signature characteristic information acquisition part configured to obtain the signature behavioral characteristic information of the entire handwritten signature to be authenticated, through the handwritten signature input part, and output the signature behavioral characteristic information;
• a first signature authentication part to which the first signature authentication algorithm is applied, and configured to output the first analysis result by applying the all pieces of the signature behavioral characteristic information input from the signature characteristic information acquisition part to the first signature authentication algorithm and by performing analysis;
• a second signature authentication part to which the second signature authentication algorithm is applied, and configured to output the second analysis result by applying the all pieces of the signature behavioral characteristic information input from the signature characteristic information acquisition part to the second signature authentication algorithm and by performing analysis, and output the third analysis result and the fourth analysis result by receiving the signature behavioral characteristic information sensitive according to the adjustment direction, by applying the received signature behavioral characteristic information sensitive according to the adjustment direction to the second signature authentication algorithm, and by performing analysis;
• an adjustment part configured to:
• obtain the first analysis result from the first signature authentication part;
• obtain the second analysis result from the second signature authentication part;
• compare the obtained first analysis result and the obtained second analysis result to the first analysis threshold values to determine the adjustment direction to determine whether to perform either adjustment of the false acceptance rate or adjustment of the false rejection rate;
• and obtain and output the third analysis result and the fourth analysis result by extracting only the signature behavioral characteristic information sensitive according to the determined adjustment direction among the all pieces of the signature behavioral characteristic information, and by applying the extracted signature behavioral characteristic information sensitive according to the determined adjustment direction to the second signature authentication algorithm;
• and
• a final authentication processor configured to determine whether authentication of the handwritten signature succeeds, by comparing the first analysis result, the third analysis result, and the fourth analysis result to the first threshold value (ρ) among the first analysis threshold values and the second analysis threshold values preset.