• 13Jul

    Recaptcha and Books Digitizing

    General Data

    Recaptcha (or reCAPTCHA) is the system that uses the millions of Captcha texts already deciphered by human internet users for the noble cause of digitizing books, newspaper archives and radio shows. ReCptcha is the little comfort we are given for all those challenging captcha texts; thanks to the time and efforts spent by millions everyday on trying to interpret those scribbled and fuzzy words, someday we will be able to browse through every ancient book on our kindles.

    The re-captcha system was developed by one of the original captcha developers, Luis von Ahn of Carnegie Mellon University who had estimated the time spent by humans on captchas as 500,000 hours a day, and, as Carsten Cumbrowski suggests, decided to reprocess the time wasted for solving captcha tests usefully for a change. Or in his own, no less self criticizing words: “Life is only like 700,000 hours, so it’s almost the equivalent of a life. We thought, is there any way we can use this human effort in a way that’s good for humanity?”

    Facebook, Twitter and many other websites have joined the mutual effort by implementing reCaptcha. In 2009, reCaptcha was obtained by Google, for its books and news search archive digitization ventures. ReCaptha’s most successful task by now is the digitization of the New York Times 130 years old archive, which started at the end of 2008 and expected to be done by the end of this year. Then what? “There’s no danger of us running out of words,” said von Ahn to BBC News at the end of 2007.
    “There are still about 100 million books to be digitized”.
    And probably no less spamming bots.

  • 05Jul

    Captcha and the Visually Challenged

    General Data

    Capthas are not very visually challenged friendly. When the average sighted internet user who is asked to type a couple of distorted half-erased words often cannot tell between l and I, an o and a 0, just imagine what the bespectacled person has to go through when he is about to send a comment or open an account somewhere. Probably the same frustration and nonsuccess the bots are meant to face.

    Although the standard captcha is usually accompanied with a disabled icon, offering the blind or visually impaired an audible version of the text, it hardly facilitates. Maybe because the audio captcha is usually as vague and ambiguous as the text captcha, and perhaps due to the unsuitable environmental conditions for careful listening an audio captcha requires.

    Fortunately, there are some captcha alternatives that help the visually impaired regain his belonging to the human society:

    -          Image captcha – where the user is asked to recognize a certain image in a group of images.
    -          Question captcha – with first grade math quizzes or simple logic questions
    -          Verification code – where an activation code is sent to your email address or cellular phone and you should verify it back.

    Other captcha alternative may include a bigger and bolder text or alpha numeric combination on a contrasting background.

  • 27Jun

    New Image Captcha for Wordpress

    General Data

    The recent Stanford University study that showed the difficulties caused by text based captcha to human beings who aim to decipher it, had expectedly pushed forward image based captcha developers.

    Thus, Confident Technologies has released its image based captcha plugin for Wordpress, stating that product is “easy on people while being tough on bots” as opposed to the frustrating, site abandoning encourager text based captcha. Confident Captcha displays a number of images, organized in a grid, asking the user to prove his humanness by clicking on one of the presented images. Users can choose the number of images and the background color to avoid the common side effect of image based captcha, its being the center of attention.

    Just released on June 23, the Confidential Captcha was downloaded only by two dozens of users (as for the moment of writing); Still, looking at some of the most popular text-based captcha plugins for Wordpress, you hardly notice a meaningful drop in the number of downloads a day, nor a huge increase in the number of image-based captcha downloads. So,difficult or not, most Wordpress users may be still hung on the good old “type the two words” captcha.

    Tags: , ,

  • 13Mar

    Captcha Script

    General Data

    Sometimes I can’t believe how poor and dull our lives have seemed before the Internet broke into them, turning them upside down… As a matter of fact, thanks to the net and the power of sharing knowledge on the net, nowdays everyone is an expert in almost any field -  just you name it!!

    Few years ago, I was completely ignorant in terms of technology. Today I can publish my own book or album, produce my own movie or song, and share them with others through social platform services –all for free!!!
    Amazing! Isn’t it?

    Those words of admiration refer to “Captcha Script” just as well.
    Captcha script is a service that can help you to write your own captcha for your site or any other online platform you own, without having to be an expert or learn a special programming language for that purpose.
    There are quite a lot of free open source captchas on the net. these resources provide captcha related services such as letting other use am already written captcha codes, generating complex images, captcha audible codes and alike – all for free.

    If you are interested in producing your own Captcha script all you have to do is purchase a PHP, Perl or Net, search for free capctha script and create your own codes. Implementation is extremely easy.
    Need an example? Take JCaptcha – a website provides a step by step guide on how to set up a captcha using Java.

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  • 30Jan

    Open Source Captcha

    General Data

    If you own a website, a forum or a blog which requires users registration, and are anxious to block those endless spam bots – you certainly need Captcha.

    Captcha is a small security image of distorted letters, and/or numbers, that is supposed to be copied by users in order to distinguish them (human users) from computers so the unwanted bots could be filtered out.

    How can you use Captcha on your site?
    You can buy captchas or get it for free, using an open source Captcha.

    Following is a small list of Open Sources Captchas,
    free resources for Captcha creation and/or implementation:

    simple-captcha

    “Simple Captcha” is an open source Java  implementation for creating Captchas.  It gives assistance in generating good looking Captchas with a minimum of programming and little configuration.

    jcaptcha

    JCaptcha is another open source Java framework for Captcha integration and definition.

    securimage

    “Securimage” is an open source Captcha script, for creating complex  images and Captcha codes. It can be easily added to an existing form on the website, and can run on most web servers as long as you have PHP installed. It generates Captcha images, it validates the typed codes, audible codes, it does everything!

    joomla

    “Joomla” is an open source CMS that has free Captcha plugins.

    plone

    Plone Captcha is a free service for Plone captchas implementation for validating human input in online forms.

    Later Addition:
    # ASPxCaptcha – check this post to watch an introduction video on how to setup the ASPxCaptcha control on your site.
    # Check this post for some easy instructions on how to implement captcha into cakephp.

  • 01Aug

    Recaptcha Definition | What is Recaptcha

    General Data

    What is ReCaptcha?

    To understand what is reCaptcha we first need to define the term “Captcha”.
    Captcha is a test made of an image and distorted text that has to be solved by human users when they want to subscribe to websites that want to make sure the user is a human being and not a bot or a computer (= preventing spam).

    Recaptcha is a system that uses Captchas to digitize books text for the same purpose: to ensure the user is not a computer or bot.
    Computers can’t navigate sites that are protected by Captchas.

    Every day 200 millions of Captchas are being solved. It takes about 10 second to decipher a Captcha but about 150,000 hours of work to accumulate them. This is where reCaptcha comes and help in channeling the big effort spent on Captchas solving into reading books by digitizing process.

    How is it done?
    By using Optical Character Recognition (OCR) program books text and pages are scanned and transformed into forms that are impossible for computers to decipher. Every word that can’t be read by OCR is placed on an image and displayed together with another word which can be read correctly, that is a “control word”. The user who wants to subscribe to a site that demands verification of human users, is asked to decipher both words. If he solves the “control word” the system assumes the answer is correct for the new one also.

    Captchas are taken from internet archives, the New York Times and alike and can be used as protector from mail spam bots as well.

  • 25Jul

    Audio Captcha for Sight Impairment or Blindness

    General Data, Interesting Captcha

    Captcha is a test that comes to validate web users as humans (=rather than computer bots).
    the captcha test can be used for site registration, for example – just before registration is completed the user is asked to copy an  image with distorted letters. Since those letters are captured in images and are displayed randomly, and bots can not “read” images, the CAPTCHA test suppose to “stop bots from passing the test and using the web for their inetrests”.

    But what about people who suffer from some kind of sight impairment including blindness?
    They can not solve the captcha test (they can not see the captcha image well and thus can not copy it) and thus, just like bots, can not register to sites and other online services that use captcha.
    But do not worry, there’s a solution for this problem and it called: Audio Captcha.

    People who suffer from sight impairment need to pass an audio captcha test in which they are asked to listen to a series of numbers or letters with a lot of background noise and then repeat them through typing the letters/numbers.
    The idea is that humans can filter the background noise but a computer bot – can’t.

    Unfortunately the audio captcha test is not perfect.
    First, there are people who suffer from sight impairment / blindness that also have hearing problems.
    Second, statistic shows that only 46% of audio captchas users are able to decipher the test and that the process takes 65 seconds at least , relatively much longer than a textual Captcha (about 12 seconds).
    Third, most of the sites don’t use audio-captchas yet.

    What other transformations will make the captcha test suitable for all?
    Only time will tell…

    Tags: , ,

  • 05Jul

    Captcha Security Applications

    Captcha & Security, General Data

    Captcha is known for its efficiency in ensuring proper use of websites and online application by validating that the user is human and not a bot or some other automatic machine.
    This article lists some of the security applications / uses of CAPTCHA:

    Comments spam prevention

    Comments spam is used in blogs and forums mostly for raising search engine ranking of websites. A “spammer” who wants to get some free traffic to his website might get into a variety of blogs or forums and add comments with textual (using keywords as the anchor) links leading to his website.
    The advantage of using captcha in blogs and forums adding comments option is that it can block automatic machines that can do this kind of spamming. Bots don’t know how to read captcha and thus cannot pass it.

    Online Surveys and Polls

    When you want to trust the results of an online poll and be sure that only human votes are counted – use Captcha. This way you’ll ensure that only human will take a part in the poll and at the same time prevent the possibility of biased results (by bots).

    Spam blockers / Protecting Email Addresses from spam scrapers

    Captcha is also known as a great spam blocker against spammers who search the web for e-mail addresses. You want to allow your users to send you emails but don’t want to get spammed by bots? All you have to do is to ask your website visitors to solve a confusing Captcha before you show your e-mail.
    Just the same, the CAPTCHA test can be used to protect from massive registration to free email accounts.

    Search Engine Bots

    Have some confidential pages on your website that you don’t want the search engine bots to reveal (and index)? Use Captcha to prevent all kinds of bots, including those of the search engines, to get to them.

    Free anti spam

    Lots of companies wish to accept mails only when they are 100% sure that the e-mail sender is not an automated machine. One of the easiest ways to get this is by using Captcha as a spam filter.

  • 01Jul

    CAPTCHA Implementations Criterions

    General Data, Interesting Captcha

    Captcha protects your website from unwanted users such as automated machines, bots and spammers. Once you have decided to use Captcha for your site, there are some important criterions you must take into consideration:

    Accessibility
    Captcha must be accessible for every user – for the normal and the blinds.
    That means that the captcha image shouldn’t be too small and it should offer an alternative (audio one for example) for the ones who can’t see well or don’t see at all.

    Image security / complexity
    Captcha images should not be easy to percept.
    They should be vague and distorted so no bot can solve it – only humans.

    Script security
    A Captcha code should consist of images that are not readable by bots as well as questions that can be answered only by using human intelligence.

    Security of CAPTCHA wide spread use

    When Captcha system is adopted by a great number of sites it could weaken its security effect, since a parser could make it easy for bots to solve the Captcha test. Since it is highly important that Captcha will be of strong security even when it is widely used, it is recommended to use well-tested implementations of *reCAPTCHA than to create your own CAPTCHA script.

    * reCAPTCHA is a free service that helps to digitize old media such as books, newspapers and radio shows so they can be used as CAPTCHAs

  • 30Jun

    Effective Online Ads and Channels

    Advertising Channels, General Data, Interesting Captcha

    Online Marketing Solutions / Online Branding Solutions
    Businesses that want to succeed in the online world should know how to market their selves, meaning they must know their target market / audience and the channels they can use in order to get to this audience.

    The following online marketing solutions can be used for branding a new business as well as for promoting an old one. Most of these marketing channels are good for most of the markets / target audiences, and yet this is not an axiom.

    My advice to you is to think thoroughly about your target market, what your potential clients are looking for and where (online) they might look for it and only after that take a step, choose your marketing sources and build your online marketing strategy.

    What are the best online marketing sources out there?

    Sponsored Links on Search Engines / Search Advertising

    Sponsored links on search engines are textual paid ads that show up on search results pages. Since these textual ads are keywords related they are considered as ads of high relevance both for the user and the advertiser.

    Two of the most popular search advertising services are Google Adwords and Yahoo! Sponsored Search.

    Banner Ads

    Banner is a clickable graphic image, used on websites, that attempts to promote a service or a product through catching the user’s attention. ‘Though banners ads come in many forms and sizes, the most common form is a rectangle image in one of the following sizes: 460 pixels wide by 60 pixels high, 460 x 55 or 392 x 72.

    Textual Ads

    Textual ads are online advertisements that use nothing but text based hyperlinks.
    The advantages of the textual ads are:
    1. They can be downloaded immediately (as opposed to banner ads).
    2. They cannot be blocked by all kinds of ads blocking programs that usually block banner ads.
    3. They are easy to assimilate within the text content and thus are considered less “pushy” in the eyes of the web user.

    SEO / Search Engine Optimization

    SEO is a method through which one can promote his site on search engines’ generic results to earn a better and highly targeted traffic.
    Promoting a website through SEO is one of the best online marketing solutions, ‘though it is just as well very time consuming. One of the reasons for this is that search results can vary from websites to landing pages to images, documents and even videos. This leads to the fact that anyone who wants his website or service to be shown in most of the search results and at the top of them, must invest lots of time and creativity as well as money in creating an appealing website, video and so on.

    SMO / Social Media Optimization
    Social Media Optimization focuses on optimizing one’s online presence within online communities and social platforms, while aiming to get this “social presence” to the top of search results.
    Facebook, for example, is a social website that can be used for business promotion through networking as well as by getting the business profile into the top of search results for a relevant term (keyword).
    See for example - http://www.facebook.com/itsyourturn

    Viral Marketing

    Viral marketing is an online marketing solution that increases brand awareness or product sales through creating a buzz on different platforms such as social platforms, emails and video websites.
    This youtube video of bing.com is a great example for the power of viral marketing.
    Since the video is funny there’s a big chance that people will forward it to their friends to watch (or link to it just like I did!) thus enhancing the awareness to bing as a new search engine and a brand. At the same time, since the video will get lots of views on youtube, there’s a high probability for it to be shown on relevant search results (see the video results at the top of the search results page for the term “bing”.

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