J Chen, X Luo, Y Guo, Y Zhang… - Security and …, 2017 - Wiley Online Library
The CAPTCHA has become an important issue in multimedia security. Aimed at a commonly used text‐based CAPTCHA, this paper outlines some typical methods and summarizes the …
K Wang, S Belongie - Computer Vision–ECCV 2010: 11th European …, 2010 - Springer
We present a method for spotting words in the wild, ie, in real images taken in unconstrained environments. Text found in the wild has a surprising range of difficulty. At one end of the …
ABSTRACT We present Asirra (Figure 1), a CAPTCHA that asks users to identify cats out of a set of 12 photographs of both cats and dogs. Asirra is easy for users; user studies indicate …
J Yan, AS El Ahmad - Proceedings of the 15th ACM conference on …, 2008 - dl.acm.org
CAPTCHA is now almost a standard security technology. The most widely deployed CAPTCHAs are text-based schemes, which typically require users to solve a text recognition …
Recent advances in deep learning (DL) allow for solving complex AI problems that used to be considered very hard. While this progress has advanced many fields, it is considered to …
Captchas are designed to be easy for humans but hard for machines. However, most recent research has focused only on making them hard for machines. In this paper, we present …
J Yan, AS El Ahmad - Proceedings of the 4th symposium on Usable …, 2008 - dl.acm.org
CAPTCHA is now almost a standard security technology, and has found widespread application in commercial websites. Usability and robustness are two fundamental issues …
R Gossweiler, M Kamvar, S Baluja - Proceedings of the 18th international …, 2009 - dl.acm.org
We present a new CAPTCHA which is based on identifying an image's upright orientation. This task requires analysis of the often complex contents of an image, a task which humans …
Human interaction proofs (HIPs) have become commonplace on the internet for protecting free online services from abuse by automated scripts/bots. They are challenges designed to …