Iris code generation method, individual authentication method, iris code entry device, individual authentication device, and individual certification program
A plurality of images that include the same eye is input (S 11 ) and iris regions are extracted therefrom to obtain iris images (S 12 ). After the plural iris images are subjected to transformation from a rectangular coordinate system to a polar coordinate system (S 13 ) and rotational compensation (S 14 ), the images are added together while a weight is attached to a pixel value in each coordinate of the polar coordinate system, to accumulate them as a single iris image (S 15 ). An iris code is generated from the thus obtained single iris image (S 16 , S 17 ).
1. An iris code generation method comprising the steps of:
a step of capturing a plurality of iris images that include a same eye;
a step of transforming a coordinate system of each of the iris images from a rectangular coordinate system to a polar coordinate system;
a step of performing rotational compensation on each of the coordinate transformed iris images;
a step of adding together each of the rotationally compensated iris images, while attaching a weight to each pixel value in each coordinate of the polar coordinate system, to accumulate them as a single iris image; and
a step of generating an iris code from the single iris image,
wherein in the weighted addition in the accumulation step,
the weight is set smaller as a distance between a coordinate value in the original rectangular coordinate system corresponding to a coordinate of the polar coordinate system and a coordinate value of a pixel in the vicinity thereof is larger.
2. An iris code generation method comprising the steps of:
a step of capturing a plurality of iris images that include a same eye;
a step of transforming a coordinate system of each of the iris images from a rectangular coordinate system to a polar coordinate system;
a step of performing band limitation on each of the coordinate transformed iris images;
a step of performing rotational compensation on the band-limited iris images;
a step of adding together each of the rotationally compensated iris images, while attaching a weight to a data value in each coordinate of the polar coordinate system, to accumulate them as a single iris image; and
a step of generating an iris code from the single iris image,
wherein in the weighted addition in the accumulation step,
the weight of a data value of which coordinate value of the original rectangular coordinate system corresponding to a coordinate of the polar coordinate system is close to an integer is set large, while the weight of a data value thereof is far from an integer is set small.
3. An iris code generation method comprising the steps of:
a step of capturing a plurality of iris images that include a same eye;
a step of transforming a coordinate system of each of the iris images from a rectangular coordinate system to a polar coordinate system;
a step of performing band limitation on each of the coordinate transformed iris images;
a step of performing rotational compensation on the band-limited iris images;
a step of adding together each of the rotationally compensated iris images, while attaching a weight to each data value in each coordinate of the polar coordinate system, to accumulate them as a single iris image; and
a step of generating an iris code from the single iris image,
wherein in the weighted addition in the accumulation step,
the weight is set smaller as a distance between a coordinate value of the original rectangular coordinate system corresponding to a coordinate of the polar coordinate system and a coordinate value of a pixel in the vicinity thereof is larger.
4. The iris code generation method of claim 2 or 3 , wherein the band limitation is performed by Gabor transformation.
5. A personal authentication method comprising the steps of:
a first step of performing authentication by generating an iris code from a single iris image captured for a person who is to be authenticated; and
a second step of performing, when the authentication in the first step results in rejection, authentication by generating an iris code from a plurality of iris images captured for the person who is to be authenticated by the iris code generation method of claim 1 .
6. A personal authentication method using an iris image, comprising the steps of:
at a time of registration,
generating an iris code from an iris image; and
registering the generated iris code in a database,
at a time of authentication,
generating an iris code from an iris image; and
performing authentication by comparing the thus generated iris code with the iris code registered in the database,
wherein at one or more of the time of registration and the time of authentication, iris code generation is performed by the iris code generation method of claim 1 .
7. An iris code registration device comprising:
a code generation section that generates an iris code by the iris code generation method of claim 1 ; and
a registration section that registers in a database an iris code generated by the code generation section.
8. A personal authentication device, comprising:
a code generation section that generates an iris code by the iris code generation method of claim 1 ; and
an authentication section that performs authentication by comparing an iris code generated by the code generation section with a registered iris code.
9. A personal authentication program encoded on a computer readable medium to execute the steps of:
a code generation step of generating an iris code by the iris code generation method of claim 1 : and
an authentication step of performing authentication by comparing the iris code with an iris code registered in a database.
10. A personal authentication method comprising the steps of:
a first step of performing authentication by generating an iris code from a single iris image captured for a person who is to be authenticated; and
a second step of performing, when the authentication in the first step results in rejection, authentication by generating an iris code from a plurality of iris images captured for the person who is to be authenticated by the iris code generation method of claim 2 .
11. A personal authentication method using an iris image, comprising the steps of:
at a time of registration,
generating an iris code from an iris image; and
registering the generated iris code in a database,
at a time of authentication,
generating an iris code from an iris image; and
performing authentication by comparing the thus generated iris code with the iris code registered in the database,
wherein at one or more of the time of registration and the time of authentication, iris code generation is performed by the iris code generation method of claim 2 .
12. An iris code registration device comprising:
a code generation section that generates an iris code by the iris code generation method of claim 2 ; and
a registration section that registers in a database an iris code generated by the code generation section.
13. A personal authentication device, comprising:
a code generation section that generates an iris code by the iris code generation method of claim 2 ; and
an authentication section that performs authentication by comparing an iris code generated by the code generation section with a registered iris code.
14. A personal authentication program encoded on a computer readable medium to execute the steps of:
a code generation step of generating an iris code by the iris code generation method of claim 2 : and
an authentication step of performing authentication by comparing the iris code with an iris code registered in a database.
15. A personal authentication method comprising the steps of:
a first step of performing authentication by generating an iris code from a single iris image captured for a person who is to be authenticated; and
a second step of performing, when the authentication in the first step results in rejection, authentication by generating an iris code from a plurality of iris images captured for the person who is to be authenticated by the iris code generation method of claim 3 .
16. A personal authentication method using an iris image, comprising the steps of:
at a time of registration,
generating an iris code from an iris image; and
registering the generated iris code in a database,
at a time of authentication,
generating an iris code from an iris image; and
performing authentication by comparing the thus generated iris code with the iris code registered in the database,
wherein at one or more of the time of registration and the time of authentication iris code generation is performed by the iris code generation method of claim 3 .
17. An iris code registration device comprising:
a code generation section that generates an iris code by the iris code generation method of claim 3 ; and
a registration section that registers in a database an iris code generated by the code generation section.
18. A personal authentication device, comprising:
a code generation section that generates an iris code by the iris code generation method of claim 3 ; and
an authentication section that performs authentication by comparing an iris code generated by the code generation section with a registered iris code.
19. A personal authentication program encoded on a computer readable medium to execute the steps of:
a code generation step of generating an iris code by the iris code generation method of claim 3 : and
an authentication step of performing authentication by comparing the iris code with an iris code registered in a database.
20. A personal authentication method comprising the steps of:
a first step of performing authentication by generating an iris code from a single iris image captured for a person who is to be authenticated; and
a second step of performing, when the authentication in the first step results in rejection, authentication by generating an iris code from a plurality of iris images captured for the person who is to be authenticated by the iris code generation method of claim 4 .
21. A personal authentication method using an iris image, comprising the steps of:
at a time of registration,
generating an iris code from an iris image; and
registering the generated iris code in a database,
at a time of authentication,
generating an iris code from an iris image; and
performing authentication by comparing the thus generated iris code with the iris code registered in the database,
wherein at one or more of the time of registration and the time of authentication, iris code generation is performed by the iris code generation method of claim 4 .
22. An iris code registration device comprising:
a code generation section that generates an iris code by the iris code generation method of claim 4 ; and
a registration section that registers in a database an iris code generated by the code generation section.
23. A personal authentication device, comprising:
a code generation section that generates an iris code by the iris code generation method of claim 4 ; and
an authentication section that performs authentication by comparing an iris code generated by the code generation section with a registered iris code.
24. A personal authentication program encoded on a computer readable medium to execute the steps of:
a code generation step of generating an iris code by the iris code generation method of claim 4 : and
an authentication step of performing authentication by comparing the iris code with an iris code registered in a database.