=Paper=
{{Paper
|id=Vol-409/paper-4
|storemode=property
|title=Walking on the Web: Combining User-driven Location Mapping and Mobile Visualization
|pdfUrl=https://ceur-ws.org/Vol-409/Paper4.pdf
|volume=Vol-409
}}
==Walking on the Web: Combining User-driven Location Mapping and Mobile Visualization==
https://ceur-ws.org/Vol-409/Paper4.pdf
Walking on the Web - Combining
User-driven Location Mapping and Mobile Visualization
Matthias Baldauf, Peter Fröhlich
Telecommunications Research Center Vienna (ftw.)
{ baldauf, froehlich }@ftw.at
Abstract. Today’s georeferencing approaches and Location-Based Services
(LBS) are primarily closed, domain-specific applications. In this paper, we
introduce our vision of an ‘Open Spatial Repository’ as a first step towards
loosely coupled LBS. To illustrate this idea, we present a novel location-aware
Web browsing metaphor: according to a user’s location and her current
surrounding, the ‘Real World Web Browser’ allows the visual discovery and
access of georeferenced services and thereby enables new use cases beyond
common tourist guides and static points-of-interest (POIs).
Keywords: Mobile Web, Location-Based Services, Visualization
1 Introduction
‘Volunteered geographical information’ (VGI) [6], the Web-based creation of
geographic information by individuals, has recently attracted enormous interest.
Countless Websites make use of map mashups and provide ways to annotate digital
information with related geographic identifiers - a process also referred to as
georeferencing or geotagging. Wellknown examples include photo community sites
such as Flickr1 or Panoramio2 with hundreds of thousands of geotagged user-
submitted photos, Wikimapia3 assigning articles of the famous online encyclopedia to
the place of action or OpenStreetMap4 creating a free source of map data. Even
commercial navigation solutions providers such as TomTom5 build on the user’s
knowledge to keep their map content accurate and up-to-date. Similarly, semantic
approaches to mark spatial information in plain HTML such as Microformats, Dublin
core and RDFa are increasingly applied.
At the same time, the technical access to such geotagged resources is simplified by
the penetration of location-aware devices such as latest mobile phones equipped with
built-in GPS receivers. In recent years the rendering quality of mobile Web browsers
offered for such devices increased as well making them well-suitable for visualizing
online content.
1 http://www.flickr.com
2
http://www.panoramio.com
3 http://www.wikimapia.com
4 http://www.openstreetmap.com
5 http://www.tomtom.com/mapshare
2 Walking on the Web - Combining
User-driven Location Mapping and Mobile Visualization
Combining these developments, we argue for a more efficient and consistent usage
of VGI, striving for a loosely-coupled engineering approach to realize the ‘Locative
Web’ [9]. This paper introduces the vision of the ‘Open Spatial Repository’, a
catalogue where geographic identifiers can be attached to arbitrary online resources
pioneering the way for novel location-aware applications. As an illustrating example
we present a mobile application called ‘Real World Web Browser’ suggesting a new
location-based metaphor for browsing the mobile Web. Finally, we draw some
concluding remarks about potential limitations and future work.
2 The Open Spatial Repository
In order to realize our idea of location-aware mobile Web browsing, we introduce
the concept of the ‘Open Spatial Repository’ (OSR). Already mentioned tagging
approaches to mark location-related information in HTML are a first step towards
semantic meaningful Web content. But to efficiently execute spatial queries we need
an external public accessible catalogue of Web resources mapped to their
corresponding real world coordinate(s). Current geotagging practices on user-driven
Web sites such as Wikimapia suffer from two main drawbacks.
First, most of them pursue a domain-specific purpose as for example mapping
articles of the online encyclopedia to the described real world objects (Wikimapia and
Placeopedia6) or geotagging uploaded photos (Flickr and Panoramio), other services
like GeoURL7 or GeoSearch8 are restricted to Website-location mappings. Our
proposed repository is supposed to support arbitrary types of online data connected to
a real world position, e.g. any type of a Uniform Resource Identifier (URI), whether it
identifies a Web page, a photo, a file download or any form of a Web service. This
feature enables novel location-aware applications beyond current POI-based tourist
guides.
Second, current geotagging Web applications usually collect user-generated
annotations but do not make these data available for external software limiting the
possible usage of this information. What is needed is the access to user-generated
applications by an extensive interface for adding and querying data records. To
increase the end-user’s interaction possibilities and to take full advantage of existing
data sources, location data and referenced resources have to be completely separated
from actual applications and made available for public use. The proposed OSR is a
first step towards this vision.
In a simple prototype we implemented the repository as a user-driven Web
catalogue similar to a wiki where users are able to edit other users’ entries. Via a
standard Web interface contributors are allowed to assign real world locations (in
terms of WGS84 coordinates) to URIs. While some URIs have exactly one real
counterpart (e.g. a Website describing a monument), others may have several real
world representations (e.g. a public transport service may be attached to all stations
6 http://www.placeopedia.com/
7 http://geourl.org
8 http://geotags.com
Walking on the Web - Combining
User-driven Location Mapping and Mobile Visualization 3
and stops with different parameters). Optional attributes include validity parameters
limiting the item’s visibility for possible usage in specialized location-based
applications: a radius may be determined in meters as well as time intervals similar to
a shop’s opening hours. Furthermore we suppose the attaching of arbitrary textual
tags to URIs for later categorization and recommendation.
This user-based location tagging approach is thought as a complementation of
large-scale automated registration techniques using data mining approaches such as
presented in [1,3]. Still, for Web services such as services offered via SOAP and other
digital resources, a manual registration process is necessary.
3 Real World Web Browser
This mobile application installed on a location-aware mobile phone makes use of the
proposed OSR and displays Websites available in your current visible surroundings.
Our ‘real world Web browsing approach’ follows the ‘Smart Horizon’ concept, which
considers a mobile device as a virtual window beyond the user’s current field of view
[4,5]. To apply an appealing environmental visualization we build upon work done in
the ongoing Austrian research project WikiVienna, where a community-based
approach to reconstruct an urban model is investigated. We make use of a hosted
rendering service returning an on-demand rendered panorama image according to the
passed location [2] (see e.g. [7] for a similar approach offering panoramic sketches of
mountain views). This image is augmented with the surrounding referenced Websites.
The nearby items returned by a spatial query on the OSR passing an appropriate
bounding box are limited to the currently visible ones by a visibility calculation
engine [8] returning the visible items’ distances and angles in relation to the passed
user’s position. We use the Websites’ so-called Favicons or, if not available, an
abstract icon to visualize the visible ‘physical hyperlinks’ on the rendering.
Fig. 1a. Augmented Fig. 1b. Preview Fig. 1c. Web browsing
rendering zooming in in browser component
To avoid an annoying occultation of the rendered scene, all unselected icons are
semitransparent (1a). When an icon is picked, a former generated preview of the
4 Walking on the Web - Combining
User-driven Location Mapping and Mobile Visualization
Website zooms in (1b). In order to best possible resemble the Websites’ appearance if
afterwards opened in the integrated browser component, we analyze the client’s
HTTP user-agent string. This common way to determine the requesting device’s type
allows us to manipulate the desktop browser used for rendering the preview images
according to the users’ mobiles. After previewing the site, the user may chose to open
the Website in the integrated browser component for the common Web browsing
experience (1c).
4 Conclusions
In this paper we introduced our vision of the Open Spatial Repository, where
arbitrary digital resources can be mapped to corresponding real world locations. As a
method to make the wealth of spatially-related Web resources around a mobile user,
we proposed the ‘Real World Web Browser’. The prototypical OSR can be extended
in several ways. Besides the obvious integration of an automated crawling and
geotagging of resources, a recommender engine providing similar nearby content to
the one currently viewed would be a useful feature.
The presented preliminary mobile prototype exemplifies some general challenges
arising from the real world browsing approach. A long-known but still critical
problem is the insufficient adaptability of most Web sites to the restricted interaction
capabilities of mobile devices. Another strong future research challenge is to manage
the sheer amount of available Web information for certain places. In order to filter,
sort and place the information in real world browsing user interfaces, the integration
of the user context in form of a user model containing personal information,
preferences and physiological data should be advanced to recommend suitable
resources.
Regarding the user perspective, we are interested in the effect of georeferenced
interactive services in contrast to static location-based information offered by
common location-aware applications. Do they provide any additional value beyond
static points-of-interest in the standard tourism scenario? Future research should help
realizing the vision of bringing the Web’s full interaction potential to the focus points
of daily life.
Acknowledgements
This work has been carried out at ftw. within the projects WikiVienna (funded by the
city of Vienna within the WWTF program) and U0 (funded by the city of Vienna and
the Austrian government within the competence center program COMET).
References
1. Amitay, E., Har'el, N., Sivan, R. & Soffer, A. Web-a-where: geotagging Web content.
Proceedings of the 27th annual international ACM SIGIR conference on Research and
development in information retrieval. 2004.
Walking on the Web - Combining
User-driven Location Mapping and Mobile Visualization 5
2. Baldauf, M., Fröhlich, P., Musialski, P. A Lightweight 3D Visualization Approach for
Mobile City Exploration. First International Workshop on Trends in Pervasive and
Ubiquitous Geotechnology and Geoinformation. 2008.
3. Clough, P. Extracting metadata for spatially-aware information retrieval on the internet.
Proceedings of the 2005 workshop on Geographic information retrieval. 2005.
4. Egenhofer, M. J. Spatial Information Appliances: A Next Generation of Geographic
Information Systems. First Brazilian Workshop on GeoInformatics. 1999.
5. Fröhlich, P., Obernberger, G., Simon, R., and Reichl, P. (2008). Exploring the Design
Space of Smart Horizons. Proc. Mobile HCI 2008.
6. Goodchild, M. Citizens as sensors: the world of volunteered geography. GeoJournal 69.
2007.
7. Hey, what’s that? 9 Sept. 2008. http://www.heywhatsthat.com/
8. Simon, R., Fröhlich, P. A Mobile Application Framework for the Geospatial Web. In
Proceedings the 16th International World Wide Web Conference. 2007.
9. Wilde, E., Kofahl, M. The Locative Web. Proceedings of the First International Workshop
on Location and the Web (LocWeb 2008). 2008.