Information processing apparatus and signature data input programs

1. An information processing apparatus comprising:

an input device which inputs coordinate data and pressure data corresponding to a signature which is handwritten by a stylus;

a determining unit configured to determine whether the stylus lifts off the input device, based on the pressure data input by the input device;

a sensing unit configured to sense a completion of input of a handwritten signature when a lift-off state of the stylus continues for a given period of time;

a detecting unit configured to detect an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

an extracting unit configured to extract a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

a defining unit configured to defines, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

2. The information processing apparatus according to claim 1 , wherein the extracting unit includes a unit which extracts, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

3. The information processing apparatus according to claim 1 , further comprising a verifying unit configured to verify whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the information processing apparatus.

4. An information processing apparatus comprising:

an input device which inputs coordinate data and pressure data corresponding to a signature which is handwritten by a stylus;

a button which inputs data indicating that a handwritten signature has been input to the input device;

a sensing unit configured to sense a completion of input of the handwritten signature in response to the data input from the button;

a detecting unit configured to detect an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

an extracting unit configured to extract a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

a defining unit configured to defines, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

5. The information processing apparatus according to claim 4 , wherein the extracting unit includes a unit which extracts, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

6. The information processing apparatus according to claim 4 , further comprising a verifying unit configured to verify whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the information processing apparatus.

7. A program stored in a computer-readable medium and causing a computer to input signature data, the computer including an input device which inputs coordinate data and pressure data corresponding to a signature which is handwritten by a stylus, the program comprising:

causing the computer to perform an operation of determining whether the stylus lifts off the input device, based on the pressure data input by the input device;

causing the computer to perform an operation of sensing a completion of input of the handwritten signature when a lift-off state of the stylus continues for a given period of time;

causing the computer to perform an operation of detecting an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

causing the computer to perform an operation of extracting a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

causing the computer to perform an operation of defining, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

8. The program according to claim 7 , wherein the extracting operation includes an operation of extracting, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

9. The program according to claim 7 , further comprising causing the computer to perform an operation of verifying whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the computer.

10. A program stored in a computer-readable medium and causing a computer to input signature data, the computer including an input device which inputs coordinate data and pressure data corresponding to a signature which is handwritten by a stylus, the program comprising:

causing the computer to perform an operation of sensing a completion of input of a handwritten signature in response to an operation of a button to input data indicating a completion of input of the handwritten signature;

causing the computer to perform an operation of detecting an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

causing the computer to perform an operation of extracting a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

causing the computer to perform an operation of defining, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

11. The program according to claim 10 , wherein the extracting operation includes an operation of extracting, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

12. The program according to claim 10 , further comprising causing the computer to perform an operation of verifying whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the computer.

13. A method of inputting signature data corresponding to a signature which is handwritten to an input device of an information processing apparatus, the input device inputting coordinate data and pressure data corresponding to the signature which is handwritten by a stylus, the method comprising:

determining whether the stylus lifts off the input device, based on the pressure data input by the input device;

sensing a completion of input of a handwritten signature when a lift-off state of the stylus continues for a given period of time;

detecting an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

extracting a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

defining, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

14. The method according to claim 13 , wherein the extracting includes extracting, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

15. The method according to claim 13 , further comprising verifying whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the information processing apparatus.

16. A method of inputting signature data corresponding to a signature which is handwritten to an input device of an information processing apparatus, the input device inputting coordinate data and pressure data corresponding to the signature which is handwritten by a stylus, the method comprising:

sensing a completion of input of a handwritten signature in response to an operation of a button to input data indicating a completion of input of the handwritten signature;

detecting an actual stroke end point at which the stylus contacts the input device last, when the completion of input of the handwritten signature is sensed;

extracting a given number of items of coordinate data input after the actual stroke end point, as effective air stroke data after the actual stroke end point, from the coordinate data and pressure data both input during a period of time from the actual stroke end point to sensing of the completion of input of the handwritten signature; and

defining, as signature data corresponding to the handwritten signature, the coordinate data and the pressure data both input during a period of time from a signature input start point at which the stylus contacts the input device first to the actual stroke end point and the coordinate data extracted as the effective air stroke data.

17. The method according to claim 16 , wherein the extracting includes extracting, as the effective air stroke data, the coordinate data and the pressure data both input during the given period of time after the actual stroke end point.

18. The method according to claim 16 , further comprising verifying whether the handwritten signature is valid by comparing the defined signature data with signature data stored in advance in a storage device in the information processing apparatus.