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CAPTCHA: The Concept
“Humans can read distorted text whereas
computers cannot.”
The most common CAPTCHAs require an user to type the letters of a distorted image.
Why Turing Test
A Turing test is used to test a machine’s capability to demonstrate intelligence.
Proposed by Prof. Alan Turing.
Why Turing Test
In a simple turing test a human judge engages in natural language conversation with two parties: one human and the other computer.
CATCH: If during the conversation the judge cannot tell which is which then the machine is said to pass the test.
CAPTCHA vs. Turing Test
Unlike the turing test in which a human judge administers the test, in CAPTCHAs it is the computer which administers the test.
A CAPTCHA is also known as a reverse turing test.
CAPTCHA vs. Turing Test
Dates back to 1997 at AltaVista, a very popular search engine firm, to prevent automated programs from adding URLs to its search engines.
In 2000, von Ahn and Blum simulated situations to make images resistant to Optical Character Recognition (OCR) programs .
CATCH: They went through scanner manuals to simulate situations that resulted in a bad OCR.
For more details about Captchas with full report,please go through:
http://studentbank.in/report-captchas?pi...4#pid30164
