Mask based challenge response test.

(54) Title: PROOF OF ANSWER TO THE MASKING BASED CHECK QUESTION. (54) Title: MASK BASED CHALLENGE RESPONSE TEST.

(57) Summary

A method, apparatus and computer program for providing a test response to the associated checking question by a computational resource, the method comprises the step of: generating a test image responding to the checking question, comprising the steps of : providing a first substantially well-formed image, comprising a first disguised image having a visible portion fully composed of portions of a correctly formed first image and a first plurality of image elements; and supplying at least one poorly shaped image, each of at least one poorly shaped image comprises a second cloaked image comprising at least a first poorly shaped portion.

(57) Abstract

A method, apparatus and Computer program for providing a challenge response test associated with a Computer resource, the method comprising the step of: generating a challenge response test image comprising the steps of: providing a first substantially well-formed image, comprising a first masked image having a visible portion entirely composed of portions of a first well-formed image, and a first plurality of image elements; and providing at least one IIformed image, each at least one ill-formed image comprising a second masked image comprising at least one first illformed portion.

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Mexican Institute of Property

Industrial 13

PATENT TITLE NO. 337750

Owner (s): INTERNATIONAL BUSINESS MACHINES CORPORATION

Address: New Orchard Road, Armonk, New York, 10504, USA

Name: PROOF OF ANSWER TO THE MASKING BASED CHECK QUESTION.

Classification: Int.CI.8: G06F21 / 30

Inventors): OLGIE RD STANISIAW PIECZUL; STEPHEN PAUL KRUGER

REQUEST

Number:

MX / a / 2012/014531

International filing date:

June 2011

PRIORITY

Country:

Date:

Number:

EP

June 2010 EP June 28, 2010

10167535.3

10167536.1

Validity: Twenty years

Expiration Date: June 24, 2031

The reference patent is granted based on articles * 1 ”, 2 * section V, 6 ° section III, and 59 of the Industrial Property Law.

In accordance with article 23 of the Industrial Property Law, this patent has a validity of twenty non-expendable years, counted from the filing date of the international application and is subject to the payment of the fee to keep the rights in force. .

Whoever signs this title does so based on the provisions of articles 6, sections III and 7, bis 2 of the Industrial Property Law (Official Gazette of the Federation (DOF) 06/27/1991, amended on 02 / 08/1994, 10/25/1996, 12/26/1997, 05/17/1999, subsection a), 4th and 12th fractions I and III of the Regulations of the Mexican Institute of Industrial Property (DOF 12/14/1999, amended on 07/01/2002, 07/15/2004, 07/28/2004 and 09/07/2007); Articles 1, 3, 4, 5, section V, subsection a), 16 sections I and III and 30 of the Organic Statute of the Mexican Institute of Industrial Property (DOF) 12/27/1999, amended on 10/10/2002, 07/29/2004, 08/04/2004 and 09/13/2007); 1, 3 and 5 subsection a) of the Agreement that delegates powers to the Deputy Directors General, Coordinator, Divisional Directors, Holders of the Regional Offices, Divisional Deputy Directors, Departmental Coordinators and other subordinates of the Mexican Institute of Industrial Property. (DOF 12/15/1999, amended on 02/04/2000, 07/29/2004, 08/04/2004 and Í3 / 09 / 20Ó7).

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Issue Date: March 16, 2016

DIVISIONAL DIRECTOR OF PATENTS

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NAHANNY CANAL REYES

Arenal No. 550. Floor 1, I heard. Pueblo Santa María Tepepan,

Xoclrmilcc, CP 16020,

Mexico City

Te¡ (56) 53 3-4 07 OOwww.impi qob.mx

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MX / 2016/21926

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$5 $ 3

PROOF OF ANSWER TO THE PURCHASE QUESTION:

A MASK

Technical Field of the Invention The present invention relates to tests to answer the verification question. In particular terms, the present invention relates to an apparatus and method for providing a test response to the associated check question by a computational resource.

Background of the Invention

A CAPTCHA (Fully Automated Public Turing Test to Distinguish Computers from Humans) is a commonly asked question answer question in computer science to ensure that someone who answers a test performed by a server is a human and not another computer. Humans usually have no difficulty passing the test, but other computers actually have difficulty, because testing usually requires cognitive abilities that other computers do not. Therefore, if the test passes, the server presenting the test assumes that the respondent is human. The server can then allow the respondent access to a protected computational resource associated with the test.

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A common use of a CAPTCHA is to

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you want to access an internet resource, for example a database on a server. Before the user can access the database, a proof is presented. If the user passes the test, access to the database is allowed. If the user fails the test, access to the database is denied. Captchas can be used therefore discourage automated access attack requests on web services. However, if a computer can correctly respond to a CAPTCHA, the computer can gain access to the protected computational resource. An example of a use of a CAPTCHA is for websites that provide free email accounts. Such websites are generally attractive to people sending spam, who are interested in opening multiple email address accounts from which to send spam. In this example, a registration process protected by a CAPTCHA is useful to discourage the automatic acquisition of accounts from the email address.

Existing captchas are fallible, because cracking algorithms have been developed for computer programs to solve such tests developed so far. New captchas can crack unless the test is so complex that the cost of cracking becomes prohibitively high.

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An example of a prior CAPTCHA technique requires a human user to confirm a set of symbols on a CAPTCHA image that has been presented to the user. Typically, the CAPTCHA image comprises a set of deformed symbols and backgrounds, and therefore CAPTCHA tests whether the user can recognize the deformed symbols. Common distortions include skewed symbol processing or symbol cluttering together, making image segmentation analysis difficult for a cracking algorithm. However, although such an analysis is difficult, it is not impossible. It is also difficult to present a text in a way that is easily recognizable by humans and is difficult to recognize by a device. The approach is based on the human ability to recognize individual characters. Not applicable for use by users who do not use characters from an alphabet used by the system, which is the often Latin script. However, graphical transformations of non-Latin characters can make them harder to interpret. Systems that require text input can also cause accessibility problems for people who use the keyboard with fewer devices.

Another example of a prior CAPTCHA technique requires the user to select a CAPTCHA image that has a particular property, from a set of CAPTCHA images that do not have that property. For example, the property may

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consist in that the CAPTCHA image represents a word in a particular language. A cracking algorithm could solve this by image segmentation to identify each word represented by the CAPTCHA image and a comparison of each word with words in a dictionary. An example of a selectable CAPTCHA is described in US Patent Publication 2009/0235327 Al (Jakobsson, BM, and. Al. Captchas selectable).

An alternative example of a prior CAPTCHA technique requires the user to answer a question about the relative locations of various targets represented in the CAPTCHA graphics process 650. For example, a CAPTCHA 650 image can present four commonly recognizable targets. The user may be asked to designate the target that is greater than another target. A cracking algorithm could solve this by identifying targets using common target recognition algorithms.

Therefore, there is a need in the art to address the aforementioned problem.

Provides Description of the Invention Observed from a first aspect, the present invention provides a method of providing a test response to the associated verification question by a computational resource, the method comprising the step of: generating an image of the test of answer to the verification question that includes the stages of:

supplying a first well-formed image, correcting a first masked image having a visible portion fully composed of portions of a first well-formed image and a first plurality of image elements; and supplying at least one malformed image, each at least one malformed image comprising a second masked image comprising at least a first malformed portion.

Preferably, the present invention provides a method, where: the step of providing the first well-formed image comprises the steps of: supplying the first well-formed image; placing the first well-formed image in a frame of the structure to determine a second well-formed image, comprising the first plurality of image elements; and applying, in response to the step of determining the second well-formed image, a mask to the second well-formed image to generate the first masked image; and the step of providing the at least one malformed image, comprises the steps of: generating, in response to the step of placing the first well-formed image within the framework, a malformed image, made up entirely of the first plurality of elements of the image and comprise a second malformed portion; and applying, in response to the step of generating the malformed image, a mask to the bad image ι \. · Ί:

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Preferably, the present invention provides a method, wherein the step of generating the test question answer test image further comprises the steps of: supplying the first well-formed image comprising a third plurality of image elements , where the third plurality of image elements comprises the first plurality of image elements; supplying at least a second well-formed image, comprising a fourth plurality of image elements; placing each of the third plurality of elements of the structure in a frame of the structure; placing each of the fourth plurality of elements of the structure within the framework of the structure; applying, in response to the steps of placing each of the third plurality of image elements and the fourth plurality of image elements in the frame of the frame, a first mask to the frame of the frame to generate the first masked image ; and applying, in response to the steps of placing each of the third plurality of image elements and the fourth plurality of image elements in the frame of the structure, at least a second mask to the frame of the structure to generate the at least one malformed image.

Preferably, the present invention provides a method, wherein the method further comprises the step of

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transmit the image of the answer test .. ^ the check question to a receiver.

Preferably, the present invention provides a method, wherein the method further comprises the step of:

receiving, in response to the step of transmitting the test question response test image to the receiver, a response message associated with the transmitted test question response test image.

Preferably, the present invention provides a method, wherein the method further comprises the steps of: responding to the step of receiving the response message, evaluating whether the response message equals a value associated with the image of the response test to the check question, the value indicating that the receiver has correctly identified the well-formed structure; and in response to the evaluation step that the response message equals the value, sending an authentication message to allow the recipient access to the computational resource.

Preferably, the present invention provides a method, wherein the step of placing each of the third set of elements of the structure in a frame of the structure comprises the step of placing each of the third set of elements of the structure on a grid of N x M.

Observed from a second aspect, the present invention

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provides an apparatus for providing a test response to the associated check question by a computational resource, the apparatus comprising: a generated component: for generating an image of the test response to the check question; to provide a first well-formed image, comprising a first masked image having a visible portion fully composed of portions of a first well-formed image and a first plurality of image elements; and to provide at least one malformed image, each at least one malformed image comprising a second masked image comprising at least a first malformed portion.

Preferably, the present invention provides an apparatus, where the apparatus further comprises: an analysis component to provide the first well-formed image; a location component for placing the first well-formed image in a frame of the structure to determine a second well-formed image, comprising the first plurality of image elements; and the generated component is further operable to apply, in response to the location component the determination of the second well-formed image, a mask to the second well-formed image to generate the first masked image; a manipulation component for generation, in response to the location component placement of the first image well ί

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Say ί.Λ ι:. · Λ; -: '' '~ ·¹ '· ° - · ·> · ^' 4— formed in the framework of the structure, a malformed image, completely composed of the first plurality of elements of the image and comprising a second malformed portion; and the generated component is additionally operable to apply, in response to the manipulation component that generates the malformed image, a mask to the malformed image to generate the second masked image.

Preferably, the present invention provides an apparatus, wherein the apparatus further comprises: an analysis component for providing the first well-formed image comprising a third plurality of image elements, wherein the third plurality of image elements comprises the first plurality of image elements; the analysis component is further operable to provide at least a second well-formed image, comprising a fourth plurality of image elements; a location component for placing each of the third plurality of elements of the structure in a frame of the structure; the location component is further operable to place each of the fourth plurality of elements of the structure in the frame of the structure; the generated component is additionally operable to apply, in response to the location component that places each of the third plurality of image elements and the fourth plurality of image elements in the frame of the structure, a first mask to the frame of the! · 'ϋ'. '8ϊ ^. λ f - / —- ® ...

structure to generate the first image, .aQgia.scarada; and the generated component is additionally operable to apply, in response to the location component that places each of the third plurality of image elements and the fourth plurality of image elements within the framework, at least a second mask. to the framework of the structure to generate the at least one malformed image.

Preferably, the present invention provides an apparatus, wherein the apparatus further comprises a transmission component for transmitting the test question response test image to a receiver.

Preferably, the present invention provides an apparatus, wherein the apparatus further comprises: a receive component for receiving, in response to the transmitting component that transmits the test answer to the check question graphically processes the receiver, a response message associated with the image of the test answer to the transmitted test question.

Preferably, the present invention provides an apparatus, wherein the apparatus further comprises: in response to the receive component receiving the response message, an evaluation component for evaluating whether the response message equals a value associated with the response test image to the check question, the value indicating that the receiver has correctly identified the well-formed structure; and in response to the component of

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evaluation evaluating that the response message equals the value, the transmission component is additionally operable to transmit an authentication message to allow the receiver access to the computational resource.

Preferably, the present invention provides an apparatus, where the frame of the structure comprises an N x M grating.

Observed from a third aspect, the present invention provides a computer program stored on a computer readable medium and loadable in the internal memory of a digital computer, comprising portions of the software code, when the aforementioned program is executed on a computer, to carry carry out the steps of the invention.

Advantageously, the present invention provides a check question answer test (CAPTCHA) that allows the use of the cognitive ability of humans to easily detect portions of a source image that as is part of that source image. Despite the lack of a complete picture, humans are very benign in filling in the missing information, something in which an automated process would not be very benign.

Advantageously, the present invention provides an improvement to existing systems in that it is click based, rather than forcing users to type characters. The one-click system is particularly advantageous on a portable device, because click response is easier than text input.

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Advantageously, the present invention allows more'S '*¹'complex elements a test answer to the check question to be added, for example by including different size cell windows, different color mask elements and using unusual images. These complex elements increase complexity for potential cracking algorithms, but with increasing complexity for humans responding to the answer test question.

Advantageously, the present invention allows different sizes and types of the frame of the structure, and for the reuse of masks to provide both benign and incorrect masks, for example when using rotation.

Advantageously, the present invention considerably increases the difficulty for a cracking algorithm, requiring much more processing and many complex algorithms. Advantageously, the utility is improved, because image recognition may be easier for humans than digitally transformed, often illegible texts. It also does not limit use with users who know an individual character set / alphabet or no character system at all. Accessibility is also improved, because there is no requirement to enter any text, but rather responses can be managed by a simple click, or even voice response.

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Advantageously, the present invention provides features that protect against a cracking algorithm that could try to detect a change in color in edges between adjacent parts of the image (excluding the transition between part of the image and mask), thus detecting which elements of the Contiguous images containing the content of a few different images. These advantageous features include:

- Using high resolution color images therefore it would be very rare for even contiguous pixels to be the same color. A cracking algorithm would force you to make decisions based on statistics.

- Use smaller masks that increase the amount of calculations by the amount necessary, which reduces from the spacious edges to compare the increasing number of false positives and negatives resulting in hard to compare statistical results.

Define masks in a way that will minimize several contiguous blocks of an image that provides a less material cracking algorithm to compare.

- Use different types of masks that are not trivial to detect (for example, complicated shapes and various mosaics of shapes), different each time, instead of rectangular masks as presented in the modalities. A cracking algorithm would need to first detect which parts belong to the mask and which belong to the image.

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Brief Description of the Figures

The present invention will now be described, by way of example only, in terms of preferred embodiments, as illustrated in the following figures:

Figure 1 is a block diagram representing a computer system, according to the prior art, and where a preferred embodiment of the present invention can be practiced;

FIG. 2 is a high level exemplary, schematic flowchart for providing a test answer to the associated check question by a computational resource, in accordance with a preferred embodiment of the present invention;

FIG. 3 is a block diagram depicting an apparatus operable on a server 105, 106 for providing a test answer to the check question associated with a computational resource 120, in accordance with a preferred embodiment of the present invention;

Figure 4 is a block diagram representing image elements used by the apparatus, in accordance with a preferred embodiment of the present invention;

Figure 5 is a block diagram representing images generated by the apparatus, in accordance with a preferred embodiment of the present invention.

Figure 6 represents a presentation of the images

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from CAPTCHA to a user, in accordance with a ..... preferred modi of the invention; ~~~~

Figure 7 depicts a second image of the source and an additional image, in accordance with an alternative embodiment of the present invention; and

Figure 8 is a block diagram depicting masks and images used by the apparatus, in accordance with an alternative embodiment of the present invention.

Detailed Description of the Invention Figure 1 is a block diagram representing a computer system 100, according to the prior art, and where a preferred embodiment of the present invention can be practiced. The computer system 100 comprises computer devices, such as a first server 105, a second server 106, a third server 108 and a workstation 115, connectable through a network 114, which may comprise a network with electrical installation 110 or a wireless network (not shown). An example of a network is Internet 114. A user 118 uses workstation 115 to access a resource from server 120 available on first server 105. Workstation 115 could be a portable device 115.

When user 118 enters a uniform resource locator (URL) directed from a web page 125, a request is sent to the first server 105, which displays a CAPTCHA image 135, which is displayed in a workstation window 130 115. Web page 125 is usually a hypertext layout text language (html) to render a web page from server 120 to server 105. CAPTCHA may also be available to third server 108, if third server 108 attempts automatic access to Web page 120.

Alternatively, a second server 106 is used by the first server 105 as an authentication server 106, which authenticates requests to access the resource from server 120 via using 150.

The CAPTCHA 135 image, according to the prior art, comprises two characters One 136 and B 137, which has been deformed. The distortion comprises a rotation of character B 137, and a process 138. User 118 responds to CAPTCHA by typing characters A B that are observed in an input box 140.

Figure 2, which should be read in conjunction with Figures 3-5, is a few steps of the high level exemplary schematic flow chart representation method of operation 200 to provide a test response to the associated check question by a computational resource 120 of in accordance with a preferred embodiment of the present invention. FIG. 3 is a block diagram depicting an apparatus 305 operable on a server 105, 106 to provide a test answer to the question of

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associated checking by a computational resource according to a preferred modality of the pré'serfté ÍTÍVéllUlÓIi. Figure 4 is a block diagram representing image elements 420, 440, 440a, 440b used by apparatus 305, according with a preferred embodiment of the present invention. Figure 5 is a block diagram 500 representation images 505, 510, 515 generated by apparatus 305, in accordance with a preferred embodiment of the present invention.

Figure 2 is presented as a diagram of the logical flow diagram. As such, the order represented and the steps marked are indicative of one embodiment of the method presented. Other stages and methods may be conceptualized to be equivalent in function, logic, or effect of one or more stages, or portions thereof, of the illustrated method. Furthermore, the format and symbols used are provided to explain the logical steps of the method and are intended not to limit the scope of the method.

The method begins at step 201. At step 205, a user 118 enters a uniform resource locator (URL) directed from a web page 120, and sends a URL request (not shown) to the first server 105. The First server 105 receives the URL request and identifies that the URL request is for a resource 120 that requires access to be authenticated. The first server 105 sends a CAPTCHA request associated with resource 120 to the appliance

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305. 310 components receive from apparatus 305 receive the CAPTCHA request.

In step 210 about 315 component analyzes parse the CAPTCHA request to determine an identifier for resource 120. The 310 component extracts parse a first image of source 420 from a data source 320. Examples of a data source 320 are a library 320, or data source 320 on network 114. The first image in source 420 is a well-formed image, in which the image is humanly recognizable. As an example, depicted in Figure 4, a circle 420 is used for illustration purposes only, in the preferred embodiment.

At step 215, a location component 325 sites the first image of source 420 in a frame 440 frame, comprising a set of cells, to provide a full frame frame 440a. An example of a frame 440 frame is an N x M 440 grating, such as a 5x4 grating depicted in Figure 4. The filled frame 440a frame is also a well-formed image.

440a.

At step 225, some 330 manipulate components manipulate the content of the filled frame frame 440a by the mobile cellular content in various configurations around to provide a manipulated frame frame 440b. The manipulated framework frame 440b is a malformed image comprising at least a first

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malformed portion 414. The first malformed portion 414 is inconsistent with the first image of font 420.

At step 230, about 335 components form form a mask 505. A mask 505 comprises a set of cells 512 comprising a portion 512 that allow a portion 514 of the underlying information to be visible.

In step 240, about 340 components generate apply mask 505 to the filled framework 440a to generate a well-formed image 510. The well-formed image represents the first image of source 420 in which a human can recognize that portions 514 of the image elements within the underlying cells are consistent with each other and with the first source image 420. The well-formed image 510 is a first masked image 510 composition of a visible portion of portions 514 of the first source image 420.

The 340 generate components also apply the mask 505 to the manipulated framework 440b to generate a malformed image 515. The malformed image 515 comprises a second masked image 515 composed of at least a second malformed portion 516. The second malformed portion formed 516 of the second masked image 515 is inconsistent with the first image of the source 420.

The 340 components to generate confront the well-formed image 505 and the malformed image 515 to produce an image of the test answer to the question of

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check (CAPTCHA image) 550.

In step 245, about 345 transmit components transmit the structures of the produced CAPTCHA image 550 to the workstation 115. In step 250, the transmitted CAPTCHA image 550 is displayed in a window 130 of the workstation 115. CAPTCHA challenges user 118 to identify the well-formed image 510, from the image structures of CAPTCHA 550.

User 118 selects one of structures 510, 515 as well-formed image 510, and workstation 115 sends a response message to apparatus 305.

At step 260, all 310 receive components receive the response message. At step 265, some 345 components evaluate evaluate whether the response message matches a value associated with the CAPTCHA graphically process 550, the value indicating that user 118 correctly selected the well-formed image 510. If user 118 is correct, At step 275, apparatus 305 transmits an authentication message to server 105. Server 105 supplies resource 120 to user 118's workstation 115.

The method ends at step 299.

Figure 6 depicts a presentation of the CAPTCHA images 510, 515 graphically processing 550 to user 118, in accordance with a preferred embodiment of the invention. User 118 is presented with instructions 610, arrows

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Left and Right 615 to review - each of the CAPTCHA images graphically process 550, and a select button 625 to select one of the 510, 515 images.

By pressing one of the arrows 615, one of the images 510, 515 is shown. In an alternative embodiment, the CAPTCHA images graphically process all 550 are displayed together.

It will be apparent to the expert that many different font graphics 420s could be used, and that a new first image of the 420s font should be used for each condition of a CAPTCHA. In a preferred embodiment, the dark fonts are used for the first image of the font 420. This increases the difficulty for a cracking algorithm to perform a web search for all exposed images of the displayed structures 605, 610, 615, selecting the one that returns most matches as correct.

In an alternative embodiment, the 330 manipulate components manipulate the contents of the filled frame 440a multiple periods of time to provide a set of manipulated frames 440b. The 340 generate components apply mask 505 to the manipulated frame set 440b to generate a set of malformed images 515. The 340 components to generate confront the well-formed image 505 and the malformed image 515 to produce an image of the test answer to the question

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check (CAPTCHA image) 550.

It is also apparent to the skilled person that the number of cells can be varied, and the size of portion 512 can be changed to display different amounts of portion 514 of the underlying information to be made visible.

Figure 7, which should be read in conjunction with Figure 2 and Figure 8, depicts a second image of source 720 and an additional image 725, in accordance with an alternative embodiment of the present invention. Figure 8 is a block diagram 800 representation masks 805, 810 and graphs 860, 865 used by apparatus 305, in accordance with an alternative embodiment of the present invention.

In step 210 the 315 component analyzes analyze the CAPTCHA request to determine an identifier for resource 120.

At step 225, the 330 manipulate components manipulate the contents of the filled frames 740a, 740b by reconfiguration image elements 712 of the filled frames 740a, 740b to provide a manipulated structure frame 750. The manipulated structure frame 750 comprises image elements 760 of the first filled frame frame 740a and image elements 755, 765 of the second filled frame frame 750b. The manipulation is carried out randomly. The apparatus 305 stores a record of the

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INDVSTKi which cell of the manipulated structure frame 750 came from which full structure frame 740a, 740b. In an alternative embodiment, manipulation is based on attributes of the second source image 720 and the additional image 725, eg, based on shading, shapes, or copier.

In step 230, some 335 components form form a benign mask 805. A benign mask 805 comprises a set of translucent cells 802 that allow to be the basis of information to be visible, and a set of cells 804 that do not allow to be the basis of the information to be visible. The benign mask 805 is such that when applied to the manipulated frame 750, it displays only cells of the manipulated frame 750 where there are elements of image 760 of the first filled frame 740a. The 335 components form also form an incorrect 810 mask. The incorrect mask 810 also comprises a set of translucent cells 812 that allow to be the base of the information to be visible, and a set of cells 814 that do not allow to be the base of the information to be visible. An incorrect mask 810 is a mask that when applied to the manipulated structure frame 750, shows the cells where there are image elements 7 55, 756 of the second frame structure filled

740b.

At step 240, some 340 components generate apply benign mask 805 to the manipulated framework 750

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to generate a well-formed image 8 60. The well-formed image 8 60 represents the second image of * ~ Ta FüeríEe''72T) in which a human can recognize that the portions of the image elements within the underlying cells are consistent with each other and with the second source image 720. The well-formed image 860 comprises a masked image 860 having a visible portion 862 completely composed of portions of the second source image 720.

The 340 components to generate also apply the incorrect mask 810 to generate a second malformed image

865. The second malformed image 865 comprises a masked image 865 comprising a third malformed portion

866. The third malformed portion 866 of the second malformed image 865 is inconsistent with the second image of the source 720.

The 340 components to generate confront the well-formed image 860, and each of the malformed image 8 65 to produce an image of the test answer to the test question (CAPTCHA image) 850.

In the alternative embodiment of Figure 7, the other steps of the method of Figure 2 are as described above.

In an alternative embodiment the 310 component extracts parse a set of additional images 725, and the location component 325 provides a set of full second frames 740b. The 335 components form

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MEXICAN INSTITUTE OF PROPERTY

INDUSTRIAL

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they form a set of wrong masks 810. The 340 components to generate apply the set of wrong masks 810 to generate a set of second malformed images 865 and confront the well-formed image 860, with each of the malformed images 865 to produce a image of the test answer to the check question (CAPTCHA image) 850.

In a preferred embodiment the second image from source 720, and each of the additional image set 725 is similar in terms of size, brightness, easily detectable contrast artifacts, and others.

In an alternative embodiment, to prevent cracking algorithms using mask color consistency, the colors of the mask cells are varied, randomly, or by selecting from the source image palette 720.

It will also be apparent to the expert that the different frames 440 could be used, for example a different size grating of N χ M 440, 1005, 1050, or a different frame structure of the circular of size 830. In an alternative embodiment, the CAPTCHA difficulty can be increased, for example by modifying: the sentence length of the font; the size of the matrix; or, the number of malformed structures presented to the user.

In an alternative embodiment, apparatus 305 is operable on authentication server 106.

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The aspects of the present invention are described below in terms of illustrations of Ta "TITTj77gramá and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams and the combinations of the blocks in the flowchart illustrations and / or block diagrams can be implemented by instructions of the computer program. These computer program instructions may be provided to a general-purpose computer processor, special-purpose computer, or other programmable data-processing apparatus to produce an apparatus, such as the instructions, which are executed by the computer processor or other apparatus. programmable data processing, they form means to implement function / act specified in the flowchart and / or block of the block diagram or blocks.

These instructions from the computer program may also be stored on a computer-readable medium that may be directed by a computer, another programmable data-processing apparatus, or other devices to operate in a particular way, such that the instructions stored on the computer-readable medium produce a manufactured article that includes instructions to implement the function / act specified in the flowchart and / or block of the

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The instructions of the computer program may also be loaded onto a computer, another programmable data processing apparatus, or other devices to cause a series of operational steps to be carried out on the computer, Other programmable apparatus or other devices for producing a computer implemented the process such that the instructions that the apparatus provides for processes to implement operate / act specified in the flowchart and / or block of the block or block diagram.

As will be appreciated by one skilled in the art, aspects of the present invention may be implemented as a system, method, computer program product, or computer program. Accordingly, aspects of the present invention may be presented in the form of a fully hardware modality, software modality (including firmware, resident software, microcode, etc.) or a combination software of the modality and hardware aspects that can all generally refer to here as a circuit, module or system. Furthermore, aspects of the present invention may be presented in the form of a computer program product or a computer program represented in the one or more computer readable medium (s) having the computer programming code fully supported by software.

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The computer program code for? &lt;5ciTTzar operations for aspects of the present invention can be written in any combination of one or more programming languages, including an object-oriented programming language such as Java, Smalltalk, C ++ or the like and conventional procedural programming languages, such as the C programming language or similar programming languages. The programming code can run entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer, partly on a remote computer, completely on the remote computer or server. In the latter case, the remote computer can connect to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to a external computer (for example, over the Internet using an internet service provider).

For the avoidance of doubt, the term "comprising", as used herein throughout the description and claims, should not be construed as meaning "consisting only of.