reCAPTCHA

A method for soliciting help from the general public in order to assist large, text-to-computer projects that digitize thousands of old books. Regular CAPTCHAs are the distorted words found on websites that users type back in to validate that they are humans and not computers. Every day, hundreds of millions of CAPTCHAs are entered, creating a huge pool of human resources to draw from.

In a reCAPTCHA system, the images of words that the optical character recognition (OCR) program cannot decipher are dispersed to several people in the form of a CAPTCHA to get a consensus. Originally developed by Carnegie Mellon University, reCAPTCHA was acquired by Google in 2009. For more information or to get reCAPTCHA code, visit www.recaptcha.net. See OCR and CAPTCHA.

A reCAPTCHA

A known word (left) is always sent with the bad word so that the reCAPTCHA serves as a valid CAPTCHA. After several people enter the same text for the bad word, the system considers the word properly converted.

The No CAPTCHA reCAPTCHA

In 2014, Google introduced No CAPTCHA human authentication. Most of the time, users only have to click the box. If the system fails to authenticate, a test is presented such as having to select all the animal pictures from a group that are the same species as the given image.

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References in periodicals archive

When asked why Nest does not use ReCaptcha, Sathe cited difficulty in implementing it on mobile apps, and user convenience.

How Nest, designed to keep intruders out of people's homes, effectively allowed hackers to get in

Many were also surprised to see a reCAPTCHA feature that was introduced on the login pages over the weekend.

Was CIMBClicks hacked? Here are four things you need to know

Four years ago, Google turned reCAPTCHA into a system for training AI

Why autonomous cars won't be autonomous

But such a task can also be completed by relying on crowdsourcing, through the reCAPTCHA application.

Google Maps as Cartographic Infrastructure: From Participatory Mapmaking to Database Maintenance

In addition to security issue, a recent research pointed out that existing schemes of CAPTCHA, including reCAPTCHA, are not appropriate for mobile devices.

Improving security in mobile network access using screen brightness and symbols

reCAPTCHA: Human-Based Character Recognition via Web Security Measures.

Involving elementary teachers in the design of a serious game through action-research methodology and co- creation/Involucrando a profesores de primaria en el diseno de un juego serio mediante la metodologia investigacion- accion y co-creacion

Next, in 2007 reCAPTCHA, originated by Luis Von Ahn.

DPCA: Dual Phase Cloud infrastructure Authentication

(438) Similarly, the reCAPTCHA security feature on many Web registration forms, in which users type words appearing in an image, is actually part of a worldwide effort to digitize books and other content.

Social innovation

The workshop brought together 31 attendees from industry and academia, with a strong representation from universities (42 percent of the attendees), the largest crowdsourcing customers like Google, Microsoft, and Xerox (39 percent of the attendees), and the leading crowdsourcing platforms like Amazon's Mechanical Turk, CrowdFlower, Galaxyzoo, reCAPTCHA, and Mobile-works (19 percent of the attendees).

Workshops held at the first AAAI Conference on Human Computation and Crowdsourcing: a report

William Eggers' praise for Luis von Ahn's reCAPTCHA idea overlooks one vexing problem ("Crowdsourcing Social Problems," January).

Crowdsourcing social problems