Accessibility of CAPTCHA methods
Sajad Shirali-Shahreza, Sajad Shirali-Shahreza · 2011
CAPTCHA (Completely Automatic Public Turing Test to Tell Computer and Human Apart) systems are a group of methods designed to distinguish between real human users and computer programs that are interacting with the system. Their goal is to ask questions which human users can easily answer, but current computers cannot. So their evaluation can be done in two domains: how hard are they for computers and how easy are they for humans. In this paper, we focus on the second part, and review accessibility of different types of CAPTCHA for human users, especially visually impaired and elderly people.