1,721,116 research outputs found
Visual Surveillance of Cultural Heritage Sites by means of Unmanned Aerial Vehicles (UAV)
No full textThis paper proposes an advanced technology framework that, through the use of UAVs, allows to monitor archaeological sites. In particular this paper focuses on the development of computer vision techniques such as super-resolution and mosaicking aiming at extracting detailed and panoramic views of the sites. In particular, super-resolution aims at providing imagery solutions (from aerial and remote sensing platforms) that create higher resolution views that make visible some details that are not perceivable in the acquired images. Mosaicking aims, instead, at creating a unique large still image from the sequence of video frames contained in a motion imagery clip. In this way large areas can be observed and a global analysis of their temporal changes can be performed. In general super-resolution and mosaicking can be exploited both for touristic or surveillance purposes. In particular they can be efficiently used to allow the enjoyment of the cultural heritage through a fascinating visual experience also eventually containing augmented information but also for surveillance tasks that can help to detect or prevent illegal activities
Notes on a Robust Plane Detection Approach in 3D
Full text linkThis paper addresses the issue of plane detection in 3 dimensional (3D) range images. The identification of planar structures is a crucial task in many visual-aided autonomous robotic applications. The proposed method consists in implementing, in cascade, two algorithms: Random Sample and Consensus (RANSAC) and the more recent Least Entropy-like Estimator (LEL), a nonlinear prediction error estimator that minimizes a cost function inspired by the definition of Gibbs entropy. LEL estimators allow to improve RANSAC performances while maintaining its robustness; kernel density estimation is used to classify data into inliers and outliers. The method has been experimentally applied to 3D images acquired by a Time-Of- Flight camera and compared with a stand alone RANSAC solution. The proposed solution does not require an accurate estimation of the noise variance or outlier scale. This is of fundamental practical importance as the outlier scale, while severely influencing standard RANSAC, is usually unknown a priori and hard to estimate
Underwater Robotics and Multimedia Technologies for Marine Protected Areas
No full textThe paper describes a project aiming at the development of an integrated system for the acquisition and multimedia management of environmental data. The final objective is to provide enhanced tools for the conservation and management of hot spots of biodiversity such as pSIC and both marine and terrestrial natural reserves, including vulnerable habitats. In marine habitats, anthropogenic disturbances are more di±cult to perceive than in terrestrial ones. Consequently, the submerged portion of Marine Protected Areas (MAPAs), crucial for both conservation and management, is largely inaccessible and diffcult to monitor. The main advantages of our integrated system for the acquisition of marine environmental data is represented by the low impact produced by monitoring activities and by the low costs of management. This system can be potentially very valuable for the valorization of MPAs, making them accessible to environmental tourists, for scienti ̄c purposes, and for MPAs authorities since it will be likely to improve research, safeguard and e®ectiveness in restrictions. This pilot system is expected to be installed in the MPA of Torre Guaceto (Brindisi), one of 20 Italian MPAs where such a technology could be successfully applied in the next future
Towards cognitive and perceptive video systems
No full textIn this chapter we cover research and development issues related to smart cameras. We discuss challenges, new technologies and algorithms, applications and the evaluation of today's technologies. We will cover problems related to software, hardware, communication, embedded and distributed systems, multi-modal sensors, privacy and security. We also discuss future trends and market expectations from the customer's point of view
Generating Images from Caption and Vice Versa via CLIP-Guided Generative Latent Space Search
Full text linkIn this research work we present CLIP-GLaSS, a novel zero-shot framework to generate an image (or a caption) corresponding to a given caption (or image). CLIP-GLaSS is based on the CLIP neural network, which, given an image and a descriptive caption, provides similar embeddings. Differently, CLIP-GLaSS takes a caption (or an image) as an input, and generates the image (or the caption) whose CLIP embedding is the most similar to the input one. This optimal image (or caption) is produced via a generative network, after an exploration by a genetic algorithm. Promising results are shown, based on the experimentation of the image Generators BigGAN and StyleGAN2, and of the text Generator GPT2
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A mobile application for leaf detection in complex background using saliency maps
No full textPlants are fundamental for human beings, so it's very important to catalogue and preserve all the plants species. Identifying an unknown plant species is not a simple task. The leaf analysis is one of the approach used for the plant species identification. This task can be completed also automatically by image processing techniques, able to analyse the leaf images and provide a classification based on prior information. Many methods have been proposed in literature in order to complete the whole cataloguing task, providing excellent classification results. Nevertheless, many of the proposed methods work only on images acquired in controlled lighting conditions and with uniform background. In this work we propose a mobile application for leaf analysis for the automatic identification of plant species. The application is mainly devoted to the identification and segmentation steps, resolving the main issues created by uncontrolled lighting conditions with very accurate results
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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