KR20120095603A - Method for operating database for captcha test on image basis, method, system for captcha using the same and program recording medium for the same - Google Patents

Abstract

PURPOSE: A database operation method for an image capturing based test, capturing method, system, and program recording medium are provided to simultaneously reduce the possibility of correct answer errors by storing images confirmed by users in an image database for capturing the confirmed image. CONSTITUTION: A database(410) stores a first image soring correct answers for a predetermined image factor utilized for capturing problem and a second image which does not include the correct answers. A server(430) communicates with a client(420) and includes the database. The client simultaneously receives problems for the specific image element of a first image and a second image stored in the database from the database. The client inputs a user response for the problems. The server stores the response for the second image to the database and permits the access from the client according to the response for the first image.

Description

Method for operating database for CAPTCHA test on image basis, method, system for CAPTCHA using the same and program recording medium for the same}

The present invention relates to a method for driving a database for image-based CAPTCHA test, a CAPTCHA method, a system, and a program recording medium therefor. The present invention relates to a method for driving a database for image-based CAPTCHA test, a CAPTCHA method, a system using the same, and a program recording medium therefor, which can simultaneously increase a computer error rate and a person's correct answer rate.

CAPTCHA stands for Completely Automated Public Turing Test to Tell Computers and Humans Aparts, and is used to identify users who have accessed a web server for membership, survey participation, etc.

The CAPTCHA provides a CAPTCHA problem to a user who accesses the WEB server, and makes the web server available only to a user who provides a response corresponding to the CAPTCHA problem. Captcha provides a problem that is difficult for an automated program to solve, thereby preventing the automated program from using the web server and allowing only a real person to use the web server. The automated program may be a Boat Program or the like. In other words, the Captcha method is used to distinguish whether a respondent is a real human or a computer program through a test that can be easily solved by humans but cannot be solved by current computer technology. This CAPTCHA method has played a significant role as an effective solution to security problems on the Web. For example, if a user attempts to create an ID by accessing a website (subscription), present the CAPTCHA test to the user and allow only the user who responded to the test to generate an ID. Through this, it is possible to prevent the automatic creation of ID by malicious hacking program (Bot Program) to prevent the sending of spam mails and the manipulation of survey results.

The most common Captcha problem in these Captcha tests is a character-based Captcha approach that intentionally twists letters and makes them recognized. However, in this case, as optical character recognition technology (OCR) is developed, the conventional character-based CAPTCHA method has a problem that security is penetrated by an automated program (ie, a computer). Moreover, as the computer's character recognition ability is found to be similar to or better than humans (2005, mentioned in a paper entitled Designing Human Friendly Human Interaction Proofs), improvements to the character-based captcha approach are required.

Recently, image-based CAPTCHAs have been developed that allow computers to perform computer vision tests that are more difficult than character recognition. Typical examples include the Hot CAPTCHA, which allows the computer to recognize aesthetic beauty and selects three attractive people from the nine pictures, and the Asirra CAPTCHA, which shows the pictures of dogs and cats and distinguishes them. However, Hot CAPTCHA is not suitable for actual use because the result of test response is not constant because the aesthetic standard is different from person to person, and the probability of accidentally passing the test by selecting 3 out of 9 is very high. Similarly, Asirra CAPTCHA's security problem occurred due to the development of a recognition algorithm that can distinguish dogs and cats by 82.7% success rate (2008, Machine Learning Attacks Against the Asirra CAPTCHA paper). Furthermore, since the image-based Captcha method uses a limited amount of image database compared to the character method according to the combination of characters, the same image is more likely to be queried when subjected to multiple Captcha tests. Therefore, there is an urgent need for a technique of obtaining an image in which a correct answer to a specific image element can be easily recognized only by users.

Accordingly, an object of the present invention is to provide a method for driving an image-based CAPTCHA database and a recording medium on which program instructions for the same are solved.

In order to solve the above problems, the present invention is an image database driving method used in the image-based captcha method, the method comprising the steps of selecting the candidate image captcha; Storing the selected CAPTCHA candidate image in the database; Asking a plurality of users a question about a specific image element of the CAPTCHA candidate image, so as to obtain response information from the plurality of users; And storing the response information as a correct answer for the captcha problem of the stored captcha candidate image.

According to an embodiment of the present invention, the correct answer is response information to which a predetermined number of users have responded the same, and the correct answer is response information to which the same answer is successively a predetermined number of times or more.

According to an embodiment of the present invention, the problem with the specific image element is queried to the user together with the CAPTCHA problem with another image in which the correct answer is already stored. The image is also obtained from an external database.

The present invention is an image-based captcha method, in order to solve the another problem, the method is the first image and the correct answer for a specific image element is not stored in the captcha problem for a specific image element from the captcha database Simultaneously providing the second image to the user; Authenticating a user according to a user response to the first image; If the user response to the second image is the same as the response of other users, the response is stored as a captcha problem correct answer for the second image, provides an image-based captcha method.

According to an embodiment of the present invention, when a user response to the second image is equal to or higher than a predetermined level of the response of other users, the response is stored as a CAPTCHA problem correct answer for the second image, and the second answer is stored. The image is used as an image for the CAPTCHA problem for other users.

According to an embodiment of the present invention, if the user response to the second image is less than a predetermined level with the response of other users, the user response is not stored as a correct answer to the second image.

According to an embodiment of the present invention, the image element may be a person number or a human gender.

In order to solve the above another problem, the present invention is an image-based Captcha system, the system is a database that stores the first image and the second image is stored the correct answer for a specific image element that is used as a Captcha problem ; A server comprising said database, said server capable of communicating with a client below; And a client to which a problem with a specific image element of a first image and a second image stored in the database is simultaneously transmitted from the database, wherein a user response to the transmitted problem is input, wherein the server is configured to receive the client. And permit access from the client in response to a response to the first image input from the same, and simultaneously store the response to the second image in the database.

According to an embodiment of the present invention, when the response to the second image is equal to or greater than a predetermined level with other users, the second image is stored as the first image in the database.

According to an embodiment of the present invention, when the response to the second image is less than a predetermined level with other users, the response is stored in a database and compared with another user's response.

The present invention provides a recording medium having recorded thereon program instructions for driving the above-described method and system in order to solve the another problem.

According to the present invention, by storing an image identified by a plurality of users with a correct answer to a specific image element in an arbitrary image in a captcha image database, and using it again as a captcha problem, the user's perception of the computer is significantly lowered and at the same time, The possibility of correct answer error by can be reduced at the same time. In addition, since the correct answer for image elements appearing in any image is secured in a collective intelligence manner, any image existing in an external database can be used as a CAPTCHA test problem.

1 is a step diagram of a method for driving an image database for a CAPTCHA test according to an embodiment of the present invention.
2 is a captcha candidate image photograph according to an embodiment of the present invention.
3 is a step diagram of an image-based CAPTCHA method according to an embodiment of the present invention.
4 is a schematic diagram of an image-based CAPTCHA system according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. The following embodiments are provided as examples to ensure that the spirit of the present invention can be fully conveyed to those skilled in the art. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the width, length, thickness, etc. of the components may be exaggerated for convenience. Like numbers refer to like elements throughout. In addition, abbreviations displayed throughout this specification should be interpreted to the extent that they are known and used in the art unless otherwise indicated herein.

The captcha scheme of the present invention is based on images. In other words, any information that a person can obtain from an image (hereafter, image element) such as the gender of a person, the number of people, the distinction of a dog and a cat, and the color of a specific object, etc., may be used as a test for the CAPTCHA test. have. However, the present invention is not limited thereto and may be objectively recognized by a person, but all image features not easily recognized by a computer may be used as an image element for a captcha.

In addition, the correct answer for a specific image element is stored in advance, and accordingly, an image capable of authenticating whether a respondent is a human is a first image, and an image for which a correct answer for a specific image element is not stored is referred to as a second image. do. Herein, the first or the second does not mean one or two, and means to distinguish a Captcha image, in which a correct answer is already stored, and a Captcha candidate image that are not.

The present invention first provides a new concept of database driving method for updating and expanding a database of images in which a CAPTCHA problem for a specific image element is presented in terms of collective intelligence.

1 is a step diagram of a method for driving an image database for a CAPTCHA test according to an embodiment of the present invention.

Referring to FIG. 1, first, a second image that is a captcha candidate image is selected (S110). The captcha candidate image is an image that may be used as a captcha problem according to a human response result. For example, if the gender of the person appearing in the image is an image element for the CAPTCHA problem, the face detection may be performed by a face detection algorithm, but an image in which the gender is not correctly recognized by the gender recognition algorithm may be used. Can be.

Thereafter, the image is stored in a database in which an image for captcha is stored (S210). The stored image (second image) is mixed with the first images and provided to the user at the time of the CAPTCHA test, so that specific image elements of the image are queried and user response information is obtained (S310).

In one embodiment of the present invention, the image is provided to two or more users, or two or more times. From this, identical response information about a specific image element can be obtained from the user, and the response information for which a predetermined level or more is recognized is stored as a correct answer for a later Captcha problem (S410).

2 is a captcha candidate image photograph according to an embodiment of the present invention.

Referring to FIG. 2, a photo in which a face of a person is not entirely displayed but partially hidden or cut is disclosed. For the face picture of FIG. 2, the computer detected a human face with 78% confidence, but was unable to recognize gender and other information.

The gender or number of persons of the person with respect to such an image is queried as an image element for the CAPTCHA problem, and response information from the user who is a person (for example, a woman having a gender and two people) is obtained. If response information obtained from several users shows a certain level or more of the same, the response becomes a correct answer to the CAPTCHA problem.

In the present invention, as described above, in order for the response information to be a correct answer to the CAPTCHA problem, the identity and accuracy of a predetermined level or more must be recognized. To this end, when the response information to which the plurality of predetermined users have responded the same is recognized, the response information may be a correct answer to the CAPTCHA problem. For example, when more than 95 of the 100 respondents answered that they are women in response to the CAPTCHA problem of the gender of the person shown in the image of FIG. 2, the response information of the female is stored as a correct answer to the image element of gender.

Alternatively, the response information identically or continuously answered to the question about a specific image element may be the correct answer to the CAPTCHA problem. For example, if a woman is answered equally 50 times in a row, the woman is the captcha correct answer of the image element for gender.

Afterwards, the image elements of the image that have been accepted by the user are provided to other users as a CAPTCHA problem. That is, the captcha candidate image in which the correct answer is recognized is provided to the user as an image for the captcha problem, and used as an image for user authentication.

The present invention provides an image-based CAPTCHA method using the above-described driving method database.

3 is a step diagram of an image-based CAPTCHA method according to an embodiment of the present invention.

Referring to FIG. 3, the CAPTCHA method according to the present invention firstly displays a first image in which a correct answer for a specific image element is stored from a CAPTCHA database and a second image in which a correct answer for a specific image element is not stored at the same time. It is provided (S120).

Here, the first image is an image presented to the user to determine whether the user is a person by comparing the user's response with the correct answer to the image element, and the second image receives the user's response to the image element. Presented to the user to generate images that are available in question. In one embodiment of the present invention, the image element is the number of people or person gender shown in the image, but the scope of the present invention is not limited thereto.

Thereafter, the user is authenticated according to the user response to the first image (S220). That is, if the responder's response to the first image is the same as the pre-stored correct answer, the responder is authenticated as a person, and access to a specific server or system is allowed. For example, if the respondent responds with two respondents to the Captcha question of the number of people shown in the image of FIG. 2, the response is recognized as a correct answer, and the respondent is authenticated as a person.

In addition, with a CAPTCHA test on the first image, a user response regarding a specific image element shown in the second image in which the correct answer is not confirmed is obtained (S320), and when the obtained response is the same as that of other users, the response The correct answer to the Captcha problem based on the specific image element of the second image is recognized and stored (S420).

The present invention utilizes a specific image element, which can only be identified with high accuracy, as a CAPTCHA problem in order to simultaneously increase a person's correct answer rate and a computer's wrong answer rate. Thus, the response is stored as a Captcha problem correct answer for the second image only if the user's response to the second image (more precisely, the response to a particular image element of the second image) is at least equal to the other user's response. Can be. For example, when a user who is equal to or higher than a predetermined level among a plurality of users responds to the same or successively answers the same number of times or more, the response may be stored as a correct answer for the CAPTCHA problem.

Thereafter, the second image in which responses from multiple users are correctly answered is no longer a second image but a first image, and is provided as a CAPTCHA image for another user.

Furthermore, in one embodiment of the present invention, if the user response to the second image is less than a predetermined level with another user response, the user response is not stored as a correct answer to the second image. However, such user response information is continuously stored in the database, compared with responses from other users, and when the correct answers from more than a predetermined number or more than a plurality of users are the same, the user response information for a specific image element is the correct answer for the CAPTCHA problem. Becomes

 4 is a schematic diagram of an image-based CAPTCHA system according to an embodiment of the present invention.

Referring to FIG. 4, the system includes a server 420 including a database 410 storing a first image in which a correct answer for a specific image element utilized as a CAPTCHA problem, and a second image in which the correct answer is not stored; And a client 420, such as a computer, which is in communication with the server 420, wherein a problem with a particular image element of a first image and a second image is transmitted simultaneously from the database. The client displays a first image and a second image, and inputs a user response to a specific image element question among the images. The response entered through the client is then sent to the server 430. Accordingly, the CAPTCHA system according to the present invention allows access to the server 430 from the client according to the response to the first image input from the client, and the server 430 controls whether the access is made. The server 430 also stores the user response to the second image in the database 410 and compares it with the response input from another user. If the response to the second image is equal to or higher than other users, the server converts and stores the second image as the first image in the database, and the response to the second image is the other user. If they are less than a certain level, the response is simply stored in the database and compared with other user's response.

The CAPTCHA method, system and database according to the present invention described above may be embodied as computer readable codes on a computer readable recording medium. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. Examples of the recording medium include ROM, RAM, optical disk, magnetic tape, floppy disk, hard disk, nonvolatile memory, and the like, and also include a carrier wave (for example, transmission through the Internet). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention described in the claims below. You will understand.

Claims (15)

The image database driving method used in the image-based CAPTCHA method,
Selecting a captcha candidate image;
Storing the selected CAPTCHA candidate image in the database;
Asking a plurality of users a question about a specific image element of the CAPTCHA candidate image, so as to obtain response information from the plurality of users; And
And storing the response information as a correct answer for the Captcha problem of the stored Captcha candidate image. The method of claim 1,
And the correct answer is response information to which at least one user responds in the same way. The method of claim 1,
And the correct answer is response information that is identically answered in succession more than a predetermined number of times. The method of claim 1,
The problem with the specific image element is an image database driving method used in the image-based Captcha method, characterized in that the user is asked a question with the captcha problem for another image already stored. The method of claim 1,
And the image is obtained from an external database. A recording medium on which program instructions for performing the method according to any one of claims 1 to 5 are recorded. Image-based Captcha method, the method
Simultaneously providing the user with a first image in which the correct answer for the Captcha problem for the specific image element is stored and a second image in which the correct answer for the specific image element is not stored from the captcha database;
Authenticating a user according to a user response to the first image;
And if the user response to the second image is the same as the response of other users, storing the response as a Captcha problem correct answer for the second image. 8. The method of claim 7,
And when the user response to the second image is equal to or higher than a response of other users by more than a predetermined level, the response is stored as a correct answer to the captcha problem for the second image. 8. The method of claim 7,
The second image in which the correct answer is stored is used as an image for a CAPTCHA problem for another user, image-based CAPTCHA method. The method of claim 8,
And if the user response to the second image is less than a predetermined level with the response of other users, the user response is not stored as a correct answer to the second image. 8. The method of claim 7,
And the image element is the number of persons or the gender of the person. An image-based Captcha system,
A database storing a first image storing a correct answer for a specific image element utilized as a CAPTCHA problem and a second image not storing the correct answer;
A server comprising said database, said server capable of communicating with a client below; And
A problem with a particular image element of a first image and a second image stored in the database is simultaneously transmitted from the database, and includes a client to which a user response to the transmitted problem is input, wherein the server is from the client. Permit access from the client according to the response to the input first image and simultaneously store the response to the second image in the database. 13. The method of claim 12,
If the response to the second image is equal to or greater than a predetermined level by other users, the second image is stored in the database as a first image. The method of claim 13,
If the response to the second image is less than a predetermined level with other users, the response is stored in a database and compared with the response of another user. 15. A recording medium having recorded thereon program instructions for driving an image-based CAPTCHA system according to any of claims 12-14.

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