Soumyadeb Chowdhury

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People find it difficult to remember multiple alphanumeric as well as graphical passwords. We propose a Passhint authentication system (PHAS), where the users have to choose four images and create hints for each one of them in order to register a new password. During authentication, they have to recognize only the target images, which are displayed with(More)
Lifelogging devices, which seamlessly gather various data about a user as they go about their daily life, have resulted in users amassing large collections of noisy photographs (e.g. visual duplicates, image blur), which are difficult to navigate, especially if they want to review their day in photographs. Social media websites, such as Facebook, have faced(More)
Recognition-based graphical authentication systems (RBGSs) using images as passwords have been proposed as one potential solution to the need for more usable authentication. The rapid increase in the technologies requiring user authentication has increased the number of passwords that users have to remember. But nearly all prior work with RBGSs has studied(More)
The emphasis on exhaustive passive capturing of images using wearable cameras like Autographer, which is often known as lifelogging has brought into foreground the challenge of preserving privacy, in addition to presenting the vast amount of images in a meaningful way. In this paper, we present a user-study to understand the importance of an array of(More)
The lifelogging activity enables a user, the lifelogger, to passively capture multimodal records from a first-person perspective and ultimately create a visual diary encompassing every possible aspect of her life with unprecedented details. In recent years it has gained popularity among different groups of users. However, the possibility of ubiquitous(More)
This paper presents a user study with 70 participants using four different image types: Mikon; doodle; art; object, to examine guessability of image passwords to textual descriptions The study reported in this paper will examine, whether a written (textual) copy made by an account holder for recalling the target images forming a password in subsequent use,(More)
In this paper, we describe a novel method of approving and finalising financial transactions that would raise the bar for any potential attackers. The proposed scheme is based on the hypothesis that it would be significantly harder for an attacker to compromise two hardware devices or monitor and interfere with two communication channels at the same time.(More)