By convention, CAPTCHA is an automated test that humans can pass but current computer
programs can′ t. In general, the research on CAPTCHA and Human Interactive Proofs is …

CAPTCHAs (completely automated public Turing test to tell computers and humans apart)
are in common use today as a method for performing automated human verification online …

Automated recognition of unconstrained handwriting continues to be a challenging research
task. In contrast to the traditional role of handwriting recognition in applications such as …

Abstract Human Interactive Proofs systems using CAPTCHA help protect services on the
World Wide Web (WWW) from widespread abuse by verifying that a human, not an …

Atomizing various Web activities by replacing human to human interactions on the Internet
has been made indispensable due to its enormous growth. However, bots also known as …

We present an implementation of CAPTCHA image generation as a REST-style web service,
currently available at http://captchaservice. org. We argue that CAPTCHA generation is well …

CAPTCHA. The web survival in this cut-throat competition is impossible without the
mechanisms for blocking spam-boats. The spam-boats have now been made intelligent …

A CAPTCHA is a test that a computer can automatically administer to determine if a user is a
human or a computer. Several aural and visual CAP'TCHAs have already been developed …

The massive and automated access to Web resources through robots has made it essential
for Web service providers to make some conclusion about whether a user is human or robot …

A CAPTCHA is" Completely Automated Public Turing test to tell Computers and Humans
Apart". An image of distorted letters is dynamically generated. Since the letters are a part of …