A Rarity-Based Visual Attention Map - Application to Texture Description

This paper describes a simple and "pre-cortical" visual attention model, which does not take image directions into account. We compute rarity-based saliency maps and then we describe the relation between texture and visual attention. Finally we decompose the image into several textures with different regularities. Our purpose is to compress textures into images using small repeating pattern

A Multifunctional Reading Assistant for the Visually Impaired

<p/> <p>In the growing market of camera phones, new applications for the visually impaired are nowadays being developed thanks to the increasing capabilities of these equipments. The need to access to text is of primary importance for those people in a society driven by information. To meet this need, our project objective was to develop a multifunctional reading assistant for blind community. The main functionality is the recognition of text in mobile situations but the system can also deal with several specific recognition requests such as banknotes or objects through labels. In this paper, the major challenge is to fully meet user requirements taking into account their disability and some limitations of hardware such as poor resolution, blur, and uneven lighting. For these applications, it is necessary to take a satisfactory picture, which may be challenging for some users. Hence, this point has also been considered by proposing a training tutorial based on image processing methods as well. Developed in a user-centered design, text reading applications are described along with detailed results performed on databases mostly acquired by visually impaired users.</p

Coaching - Theorie & Praxis

CAPTCHA is a standard defence mechanism against bots, or automated programs, that attempt to use web-based services meant for human users. While there are many different types of CAPTCHA schemes that have emerged over the years, to date, the most widely used type is 2D text-based CAPTCHAs. Unfortunately, a large number of 2D CAPTCHA schemes have been successfully broken. Thus, 3D-based CAPTCHAs are seen as an alternative paradigm which has been explored by a number of CAPTCHA designers. 3D CAPTCHAs are meant to overcome the limitations of 2D CAPTCHAs and are supposed to be more robust and secure against automated attacks. To investigate the robustness of 3D text-based CAPTCHAs, this paper presents an approach to breaking a representative 3D CAPTCHA scheme called Teabag 3D. In particular, this paper describes the techniques that were used to break this CAPTCHA, and as such highlights various security issues that have to be considered in order to design better 3D CAPTCHA schemes