2,822 research outputs found

    Guidance for benthic habitat mapping: an aerial photographic approach

    Get PDF
    This document, Guidance for Benthic Habitat Mapping: An Aerial Photographic Approach, describes proven technology that can be applied in an operational manner by state-level scientists and resource managers. This information is based on the experience gained by NOAA Coastal Services Center staff and state-level cooperators in the production of a series of benthic habitat data sets in Delaware, Florida, Maine, Massachusetts, New York, Rhode Island, the Virgin Islands, and Washington, as well as during Center-sponsored workshops on coral remote sensing and seagrass and aquatic habitat assessment. (PDF contains 39 pages) The original benthic habitat document, NOAA Coastal Change Analysis Program (C-CAP): Guidance for Regional Implementation (Dobson et al.), was published by the Department of Commerce in 1995. That document summarized procedures that were to be used by scientists throughout the United States to develop consistent and reliable coastal land cover and benthic habitat information. Advances in technology and new methodologies for generating these data created the need for this updated report, which builds upon the foundation of its predecessor

    Extracting Touristic Information from Online Image Collections

    Get PDF
    In this paper, we present a Geographical Information Retrieval system, which aims to automatically extract and analyze touristic information from photos of online image collections (in our case of study Flickr). Our system collect all the photos, and the related information, that are associated to a specific city. We then use Google Maps service to geolocate the retrieved photos, and finally we analyze geo-referenced data to obtain our goals: 1) determining and locating the most interesting places of the city, i.e. the most visited locations, and 2) reconstructing touristic routes of the users visiting the city. Information is filtered by using a set of constraints, which we apply to select only the users that reasonably are tourists visiting the city. Tests were performed on an Italian city, Palermo, that is rich in artistic and touristic attractions, but preliminary tests showed that our technique could successfully be applied to any city in the world with a reasonable number of touristic landmarks

    Digital representation of historical globes : methods to make 3D and pseudo-3D models of sixteenth century Mercator globes

    Get PDF
    In this paper, the construction of digital representations of a terrestrial and celestial globe will be discussed. Virtual digital (3D) models play an important role in recent research and publications on cultural heritage. The globes discussed in this paper were made by Gerardus Mercator (1512-1594) in 1541 and 1551. Four techniques for the digital representation are discussed and analysed, all using high-resolution photographs of the globes. These photographs were taken under studio conditions in order to get equal lighting and to avoid unwanted light spots. These lighting conditions are important, since the globes have a highly reflective varnish covering. Processing these images using structure from motion, georeferencing of separate scenes and the combination of the photographs with terrestrial laser scanning data results in true 3D representations of the globes. Besides, pseudo-3D models of these globes were generated using dynamic imaging, which is an extensively used technique for visualisations over the Internet. The four techniques and the consequent results are compared on geometric and radiometric quality, with a special focus on their usefulness for distribution and visualisation during an exhibition in honour of the five hundredth birthday of Gerardus Mercator

    Indexing and Retrieving Photographic Images Using a Combination of Geo-Location and Content-Based Features

    Get PDF
    This paper presents a novel method that automatically indexes searches for relevant images using a combination of geo-coded information and content-based visual features. Photographic images are labeled with their corresponding GPS (Global Positioning System) coordinates and UTC time (Coordinated Universal Time) information at the moment of capture, which are then utilized to create spatial and temporal indexes for photograph retrieval. Assessing the performance in terms of average precision and F-score with real-world image collections revealed that the proposed approach significantly improved and enhanced the retrieval process compared to searches based on visual content alone. Combining content and context information thus offers a useful and meaningful new approach to searching and managing large image collections

    eStorys: A visual storyboard system supporting back-channel communication for emergencies

    Get PDF
    This is the post-print version of the final paper published in Journal of Visual Languages & Computing. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.In this paper we present a new web mashup system for helping people and professionals to retrieve information about emergencies and disasters. Today, the use of the web during emergencies, is confirmed by the employment of systems like Flickr, Twitter or Facebook as demonstrated in the cases of Hurricane Katrina, the July 7, 2005 London bombings, and the April 16, 2007 shootings at Virginia Polytechnic University. Many pieces of information are currently available on the web that can be useful for emergency purposes and range from messages on forums and blogs to georeferenced photos. We present here a system that, by mixing information available on the web, is able to help both people and emergency professionals in rapidly obtaining data on emergency situations by using multiple web channels. In this paper we introduce a visual system, providing a combination of tools that demonstrated to be effective in such emergency situations, such as spatio/temporal search features, recommendation and filtering tools, and storyboards. We demonstrated the efficacy of our system by means of an analytic evaluation (comparing it with others available on the web), an usability evaluation made by expert users (students adequately trained) and an experimental evaluation with 34 participants.Spanish Ministry of Science and Innovation and Universidad Carlos III de Madrid and Banco Santander

    Investigating the feasibility of geo-tagged photographs as sources of land cover input data

    Get PDF
    Geo-tagged photographs are used increasingly as a source of Volunteered Geographic Information (VGI), which could potentially be used for land use and land cover applications. The purpose of this paper is to analyze the feasibility of using this source of spatial information for three use cases related to land cover: Calibration, validation and verification. We first provide an inventory of the metadata that are collected with geo-tagged photographs and then consider what elements would be essential, desirable, or unnecessary for the aforementioned use cases. Geo-tagged photographs were then extracted from Flickr, Panoramio and Geograph for an area of London, UK, and classified based on their usefulness for land cover mapping including an analysis of the accompanying metadata. Finally, we discuss protocols for geo-tagged photographs for use of VGI in relation to land cover applications

    Heritage documentation techniques and methods

    Get PDF
    This methodology notebooks "Heritage documentation techniques and methods", contains • 3D modelling, digital photography and information dissemination • Creation of 3D models by using scanners • Low-cost desktop scanner • Photography notes: Exposure • Photography notes: Focal length, lenses and cross-polarization • White adjustment and colour calibration • Image-Based Modelling Systems • Focus stacking technique • Rollout photography and DStretch filter • Information dissemination • 3D diagram blocks • Simple animations of 3D modelsEsta serie de cuadernos tiene como objetivo difundir un conjunto de técnicas usadas principalmente para la construcción y documentación de modelos tridimensionales (3D) y fotografía de alta resolución de objetos arqueológicos. Estas técnicas posibilitan construir modelos con calidad métrica contrastada, color calibrado y alta resolución que se difunden por internet usando diversas plataformas.This series of notebooks aims to describe a set of techniques used mainly to construct and document the three-dimensional (3D) models and high-resolution photographs of archaeological objects. These techniques can be used to build models with a contrasting metric quality, calibrated colour and high resolution, to be disseminated on the Internet using various platforms and web services.Parte de la realización de estos cuadernos ha sido financiada a través del proyecto GR18028 (Grupo de investigación RNM026) el cual ha sido cofinanciado por los Fondos Europeos de Desarrollo Regional (FEDER) y el Gobierno de Extremadura

    "We can remember it for you": location, memory, and commodification in social networking sites

    Get PDF
    This article explores the spatial self through the performative aspects of location sharing and geotagging in the process of self-representation on social networking sites (SNSs). Based on the legacy of early experimentations with location-based technologies for social interaction, the article asserts that the representation of location in SNSs has more temporal than spatial attributes. The article explores the immediacy of networks and the different kinds of temporality encountered in SNSs to address the commodification of geotagged content uploaded on SNSs. Location-based data are valuable commodities bought and sold in the market. Therefore, the act of archiving memories on SNSs is commodified and performed within the predetermined functions and actions set within the SNSs’ interfaces. SNSs devise ways to keep users constantly interacting with the present moment in time and simultaneously create memories of the recent past while disclosing personal data that companies use for profit
    corecore