Authentication control device, authentication control method, and authentication method

1. An authentication control device comprising:

at least one memory storing instructions; and

at least one processor configured to execute the instructions to:

receive an input associated with an authentication image that includes one base image causing a viewer to perceive a plurality of depths, a character for authentication on the base image, and a dummy character on the one base image, wherein an apparent depth of a position of the dummy character on the one base image is different from an apparent depth of a position of the character for authentication on the one base image; and

determine, based on the input, whether or not the input is made by a human.

2. The authentication control device according to claim 1 , wherein

the at least one processor is further configured to

determine whether or not an apparent depth indicated by the input, other than the apparent depth of the position of the dummy character and the apparent depth of the position of the character for authentication, is a designated depth, thereby determining whether or not the input is made by a human.

3. The authentication control device according to claim 1 , wherein

the at least one processor is further configured to:

receive the input indicating a character on the base image other than the character for authentication and the dummy character, the character having a position on the one base image-representing one of the at least one position; and

determine whether or not the position of the character indicated by the input is a designated position.

4. The authentication control device according to claim 3 , wherein

the at least one processor is further configured to

determine sizes of the character for authentication and the dummy character on the base image.

5. The authentication control device according to claim 3 , wherein

the sizes of the character for authentication and the dummy character on the base image are not correlated with the apparent depth of the position of the character for authentication and the apparent depth of the position of the dummy position, respectively.

6. The authentication control device according to claim 1 , wherein

the at least one processor is further configured to

generate the base image of the authentication image in which the character for authentication and the dummy character are included.

7. The authentication control device according to claim 6 , wherein

the at least one processor is further configured to

generate a plurality of other base images of the authentication image in addition to the one base image, and

for each other base image, a position at which the character for authentication is on the other base image and a position at which the dummy character is on the other base image are predetermined.

8. An authentication control method comprising:

receiving an input associated with an authentication image that includes one base image causing a viewer to perceive a plurality of depths, a character for authentication on the base image, and a dummy character on the one base image, wherein an apparent depth of a position of the dummy character on the one base image is different from an apparent depth of a position of the character for authentication on the one base image; and

determining, based on the input, whether or not the input is made by a human.

9. The authentication control method according to claim 8 , wherein

the determining includes determining whether or not an apparent depth indicated by the input, other than the apparent depth of the position of the dummy character and the apparent depth of the position of the character for authentication, is a designated depth, thereby determining whether or not the input is made by a human.

10. The authentication control method according to claim 8 ,

wherein the receiving includes receiving the input indicating a character on the base image other than the character for authentication and the dummy character, the character having a position on the one base image, and

wherein the determining includes determining whether or not the position of the character indicated by the input is a designated position.

11. The authentication control method according to claim 10 , further comprising

determining sizes of the character for authentication and the dummy character on the base image.

12. The authentication control method according to claim 10 , wherein

the sizes of the character for authentication and the dummy character on the base image are not correlated with the apparent depth of the position of the character for authentication and the apparent depth of the position of the dummy position, respectively.

13. The authentication control method according to claim 10 , further comprising

generating the base image of the authentication image in which the character for authentication and the dummy character are included.

14. The authentication control method according to claim 13 , further comprising

generating generating a plurality of other base images of the authentication image in addition to the one base image, wherein

for each other base image, a position at which the character for authentication is on the other base image and a position at which the dummy character is on the other base image are predetermined.

15. An authentication method comprising:

displaying an authentication image;

receiving an input associated with the authentication image that includes one base image causing a viewer to perceive a plurality of depths, a character for authentication on the base image, and a dummy character on the one base image, wherein an apparent depth of a position of the dummy character on the one base image is different from an apparent depth of a position of the character for authentication on the one base image; and

determining, based on the input, whether or not the input is made by a human.

16. The authentication method according to claim 15 , wherein

the determining includes determining whether or not an apparent depth indicated by the input, other than the apparent depth of the position of the dummy character and the apparent depth of the position of the character for authentication, is a designated depth, thereby determining whether or not the input is made by a human.

17. The authentication method according to claim 15 ,

wherein the receiving includes receiving the input indicating a character on the base image other than the character for authentication and the dummy character, the character having a position on the one base image, and

wherein the determining includes determining whether or not the position of the character indicated by the input is a designated position.

18. The authentication method according to claim 17 , further comprising

determining sizes of the character for authentication and the dummy character on the base image.

19. The authentication method according to claim 17 , wherein

the sizes of the character for authentication and the dummy character on the base image are not correlated with the apparent depth of the position of the character for authentication and the apparent depth of the position of the dummy position, respectively.

20. The authentication method according to claim 17 , further comprising

generating the base image of the authentication image in which the character for authentication and the dummy character are included.