DESIGNING A FACE DETECTION CAPTCHA Adam C. Day Completely Automated Tests for Telling Computers and Humans Apart (CAPTCHAs) are quickly becoming a standard for security in every online interface that could be the subject to spam or other exploitation. The majority of today's CAPTCHA technologies rely on text-based images, which present the user with a string of distorted characters and asks the...

The massive and automated access to Web resources through robots has made it essential for Web service providers to make some conclusion about whether the ”user” is a human or a robot. A Human Interaction Proof (HIP) like Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) offers a way to make such a distinction. CAPTCHA is a reverse Turing test used by Web serv...

Video CAPTCHA improves the usability while reducing the attack success rate compared to a conventional text-based CAPTCHA. However, it remains vulnerable to OCR attacks. Thus, we proposed to use inpainting algorithms to remove the contained text in the video frames, so that the OCR success rate can be reduced without introducing unwanted artifacts that displease the endusers. We implemented Ber...

Abuse of free Internet resources and services from false account creation, to spam, to identity theft, excessive bandwidth usage, or even vote stuffing online polls is a big problem. The Completely Automatic Public Turing Test to tell Computers and Humans Apart (CAPTCHA) controls access to resources but automated systems are increasingly adept at overcoming them. In this paper a method of acces...

A CAPTCHA is a program that can tell whether its user is a human or a computer. CAPTCHAs are used by many websites to differentiate between the bots (automated program) and the human. The main motive behind using the CAPTCHA is to prevent abuse from "bots," or automated programs usually written to generate spam. The CAPTCHA basically uses images in distorted form that is difficult to read by th...

This study focuses on a machine learning approach to the CAPTCHA recognition problem that requires minimal preprocessing of inputs. Both the feed-forward neural nets and the self-organizing maps used in this study took the raw image pixels as input with only simple segmentation and translation performed in advance. The models were trained and tested on four and five letter CAPTCHAs using either...

-------------------------------------------------------------ABSTRACT-------------------------------------------------------A novel technique of Captcha is regenerated by using composite images that are generated in the given data base. Captcha is a type of challenge response test used in computing to determine whether or not the user is human. Captcha are used to prevent bots or automated prog...

CAPTCHAs is Turing test are used to distinguish whether a user is a human or a computer. Till today huge number of CAPTCHA schema have been suggest or put forth and applied on miscellaneous websites to secure online services (SOS) from automated decaptcha programs. So development of a good CAPTCHA scheme that is both secure by automated recognition and human usable is an important research prob...

CAPTCHAs is an interesting of research are short for Completely Automated Public Turing test to tell Computers and Humans Apart. The purpose of a CAPTCHA is to block form submissions from spam bots –automated scripts that harvest email addresses from publicly available web forms. We introduce a new CAPTCHA which is based on identifying the color of image, object or background. This actually req...