Multi-factor signature authentication

1. A method of authenticating a user, comprising:

detecting a current path of a movement of a finger of the user across a sensing surface;

comparing the current path of the finger movement to a previously enrolled path of finger movement, wherein each of the current path and the previously enrolled path includes a plurality of fingerprint images comprising at least one flat fingerprint image produced by motions of sliding and at least one rolled fingerprint image produced by motions of rolling of the finger and a plurality of time data including time stamps corresponding to the plurality of fingerprint images at different locations along the respective path, and wherein said comparison is performed using the fingerprint images and the corresponding time data; and

authenticating the user based on the comparison, wherein the authenticating of the user occurs continuously at the plurality of time data corresponding to the current path as the finger moves on the sensing surface.

2. The method of claim 1 , wherein comparing the current path of the finger movement to a previously enrolled path of finger movement comprises:

comparing the plurality of fingerprint images corresponding to the current path to a set of fingerprint images of a previously enrolled path; and

comparing the plurality of time data corresponding to the current path to a set of time data corresponding to the previously enrolled path.

3. The method of claim 2 , wherein comparing the plurality of fingerprint images corresponding to the current path to a set of fingerprint images corresponding to the previously enrolled path comprises:

comparing the respective flat fingerprint images of the current path and the previously enrolled path; and

comparing the respective rolled fingerprint images of the current path and the previously enrolled path.

4. The method of claim 1 , wherein

each plurality of time stamps are measured with respect to a starting location of the respective path.

5. The method of claim 1 , further comprising:

generating multiple current paths by detecting additional current paths each corresponding to movement of one of additional fingers of the user across the sensing surface;

for each current path in the multiple current paths:

comparing the current path to a previous path of previously enrolled multiple paths of the same finger, wherein each of the current path and the previous path includes a plurality of fingerprint images comprising at least one flat fingerprint image and at least one rolled fingerprint image, and a plurality of time data corresponding to the plurality of fingerprint images at different locations along the respective path, and wherein said comparison is performed using the fingerprint images and the corresponding time data; and

wherein authenticating the user is based on the comparison of the multiple current paths and the previously enrolled multiple paths.

6. The method of claim 1 , wherein the finger movement of each of the current path and the previously enrolled path further comprising:

a sequence of taps by the finger of the user on the sensing surface,

wherein the plurality of fingerprint images further include a plurality of fingerprint images corresponding to the sequence of taps, and

wherein a plurality of time intervals between each pair of consecutive taps of the corresponding sequence of taps are collected;

wherein comparing the current path and the previously enrolled path is performed using the fingerprint images corresponding to the sequence of taps and the time intervals.

7. The method of claim 5 , wherein the finger movement of each of the current path and the previously enrolled path further comprising:

a sequence of taps by the finger corresponding to said each path on the sensing surface,

wherein the plurality of fingerprint images corresponding to said each path further include a plurality of fingerprint images corresponding to the corresponding sequence of taps, and

wherein a plurality of time intervals between each pair of consecutive taps of the corresponding sequence of taps are collected; and

wherein comparing the current path and the previously enrolled path is performed using the fingerprint images corresponding to the sequence of taps and the time intervals of said each of the current path and the previously enrolled path.

8. The method of claim 1 , wherein:

said comparing of the fingerprint images is performed on rolled fingerprint images only; and

said comparing the plurality of time data is performed on time data corresponding to the rolled fingerprint images only.

9. An apparatus for authenticating a user, comprising:

an image sensor configured to detect a current path of a movement of a finger of the user across a sensing surface;

a memory configured to store a plurality of fingerprint images and a plurality of time data corresponding to the current path; and

a controller configured to compare the current path of the finger movement to a previously enrolled path of finger movement, wherein each of the current path and the previously enrolled path includes the plurality of fingerprint images comprising at least one flat fingerprint image produced by motions of sliding and at least one rolled fingerprint image produced by motions of rolling of the finger and the plurality of time data including time stamps corresponding to the plurality of fingerprint images at different locations along the respective path, and wherein said comparison is performed using the fingerprint images and the corresponding time data; and, and authenticate the user based on the comparison, wherein the authenticating of the user occurs continuously at the plurality of time data corresponding to the current path as the finger moves on the sensing surface.

10. The apparatus of claim 9 , wherein the controller is further configured to:

compare the plurality of fingerprint images corresponding to the current path to a set of fingerprint images of a previously enrolled path; and

compare the plurality of time data corresponding to the current path to a set of time data corresponding to the previously enrolled path.

11. The apparatus of claim 10 , wherein the controller is further configured to:

compare the respective flat fingerprint images of the current path and the previously enrolled path; and

compare the respective rolled fingerprint images of the current path and the previously enrolled path.

12. The apparatus of claim 9 , wherein

each plurality of time stamps are measured with respect to a starting location of the respective path.

13. The apparatus of claim 9 , wherein the controller is further configured to:

generate multiple current paths by detecting additional current paths each corresponding to movement of one of additional fingers of the user across the sensing surface;

for each current path in the multiple current paths:

compare the current path to a previous path of previously enrolled multiple paths of the same finger, wherein each of the current path and the previous path includes a plurality of fingerprint images comprising at least one flat fingerprint image and at least one rolled fingerprint image, and a plurality of time data corresponding to the plurality of fingerprint images at different locations along the respective path, and wherein said comparison is performed using the fingerprint images and the corresponding time data; and

wherein authenticate the user is based on the comparison of the multiple current paths and the previously enrolled multiple paths.

14. The apparatus of claim 9 , wherein the finger movement of each of the current path and the previously enrolled path further comprising:

a sequence of taps by the finger of the user on the sensing surface,

wherein the plurality of fingerprint images further include a plurality of fingerprint images corresponding to the sequence of taps, and

wherein a plurality of time intervals between each pair of consecutive taps of the corresponding sequence of taps are collected;

wherein compare the current path and the previously enrolled path is performed using the fingerprint images corresponding to the sequence of taps and the time intervals.

15. The apparatus of claim 13 , wherein the finger movement of each of the current path and the previously enrolled path further comprising:

a sequence of taps by the finger corresponding to said each path on the sensing surface,

wherein the plurality of fingerprint images corresponding to said each path further include a plurality of fingerprint images corresponding to the corresponding sequence of taps, and

wherein a plurality of time intervals between each pair of consecutive taps of the corresponding sequence of taps are collected; and

wherein compare the current path and the previously enrolled path is performed using the fingerprint images corresponding to the sequence of taps and the time intervals of said each of the current path and the previously enrolled path.

16. The apparatus of claim 9 , wherein:

said compare of the fingerprint images is performed on rolled fingerprint images only; and

said compare the plurality of time data is performed on time data corresponding to the rolled fingerprint images only.