25 Mar, 2009 | Posted by: photosource


No, I didnít mean "Gotcha!" So, you ask, "Whatís a Captcha?"

You know those websites where youíre asked to decipher and type in a string of funny characters, all stretched and spaced out, or at multiple angles, different colors and conflicting backgrounds, etc?

The stuff that makes you want to rush to the phone to set up an appointment with your optometrist? Well, youíve just seen a Captcha.

Itís an acronym for Completely Automated Public Turing test to tell Computers and Humans Apart. The name recognized Alan Turing, a British computer scientist.

The Captcha system came about because Yahoo! wanted a way, back in 2000, to identify spammers that were using software to obtain huge numbers of email addresses from which they could send their spam. So, now you know, and have something to talk about at your next party.


No, itís not the old story of Pete and Repeat. Now, when you decipher a Captcha, you may be helping to digitize old books and manuscripts (like the New York Times).
How? Scanning technology is used to digitize, but like computers, scanners canít always decipher a word, due to such things as smearing, poor contrast, typestyle, etc.

So, websites that use the Captcha system to validate users can use the ReCaptcha system to present two words to the user to decipher. One is a real Captcha (thus the website knows what the correct answer is), and the other is the undecipherable scanned word.

If enough users (like maybe 3-5) correctly decode the ReCaptcha word, and have matching decodes on the Captcha word, the system presumes the ReCaptcha word has been correctly figured out.

That helps get the manuscript/book/magazine fully digitized. For more info about adding the Captcha or ReCaptcha system to your website, visit http://recaptcha.net

Is It Real or Fake?

You received an e-mail from your friend telling you that next week is "free scoop night" at an ice cream store. Is it real or fake (the free scoop offer)?
Or, you receive an urgent email saying terrorists are buying DHL uniforms on eBay. Well, hereís one place to check: http://www.snopes.com It includes a search engine so you can enter part of the suspicious offer and check the results. In case youíre wondering, yes, the free scoop night was real.

Want a browser toolbar to help you check?
Look at http://netsquirrel.com/combatkit

Bill Hopkins is the Webmaster of PhotoSourceFolio* ( http://www.photosourcefolio.com ) and a regular contributor to PhotoStockNotes. Send comments via e-mail to wh[at]photosourcefolio[dot]com Fax: 1 818 831-0916. (*Display 6 of your own images for photobuyers to view on your own page on the PhotoSource website.) For on-line questions, contact Bill on the Kracker Barrel at http://www.photosource.com/board


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