Sharing Places — share located media with the world

location based services



Associating places in the real world with digital content is an exciting development [Reid et al., 2005] that combines location technology with a new digital medium. It has attracted a lot of activity but, to date, little critical mass. We’re exploiting the power of the ideas behind Web 2.0 and the huge improvements in mobile technology to accelerate the adoption of located media.
We are combining the web with mobile devices to allow publication and sharing of users’ perspectives on spaces. Users can author content either in the field or at their desk. Photos, video, audio and text can be associated with physical locations to create a ‘mediascape’. The mediascape can be downloaded onto a GPS device and experienced in situ as the user moves around the space. Mediascapes can also be published on the web for others to download and experience, and to annotate and extend. The mediascape can be displayed with or without a map, and the map can be user-supplied or remixed from another source.
Current use of GPS is highly focused on navigation; we are changing this paradigm to a focus on exploration, discovery, sharing and interaction. Conversely much mobile technology strives to be insensitive to physical location; we are augmenting this with additional location-specific content.
Sharing places
We wanted to allow people to share their experiences and opinions about locations, and to do this sharing both on the web and in situ.
Sharing on the web means attaching textual or multimedia annotations to maps of a place, and allowing others to see or amend that content. Sharing in situ means being able to experience the multimedia content when the user is physically present in that space. The in situ sharing is dramatically augmented by using location-sensing technology to automatically trigger the content as the user moves around the physical space. We’ve focused on using GPS as the location-sensing technology.
Attaching digital multimedia to a physical space results in mediascapes [Reid et al., 2005]. These mediascapes are a powerful new medium that we want to encourage people to explore. Mediascapes connect the virtual and physical worlds, the Sharing Places service also connect the web space with the mobile space.
As a starting point in our development, we have taken the notion of a path through a space as the key narrative device. The user is able to annotate points on the path with multimedia — text, photos, audio, video — and blog-style commentary.
At the heart of our service is a simple model of create, publish and share that allows user-generated content to be shared widely. Examples of successful collections (and indeed communities) of user-generated content abound in the Web 2.0 era — Wikipedia and Flickr to name two prominent examples. Our company’s activity and approach are derived from the successful Mobile Bristol research project [Cater et al., 2005], [Hull et al., 2004].
What we’ve done
Sharing Places currently consists of three things:
a web application
which allows users to create, publish and share mediascapes online;
a handheld client
which runs on a PDA and provides automated playback of a mediascape in situ as the user follows a trail;
an open API
which is used within the webapp, between the webapp and the handheld client, and is available for third party developers wishing to take advantage of the platform.
Currently the Sharing Places website (http://sharing-places.com/) is in an invitation only beta phase. If you’re interested in becoming a beta tester drop us an email.
Web application
The web application provides a wide range of tools to help people find mediascapes: by location, by tag or by author/publisher. Users can preview a mediascape online, tag it, rate it, download it to a GPS enabled device or print it out as an annotated map.
Authors can use the map based interface to create mediascape trails from scratch or starting from an uploaded GPS trace. They can attach a range of media to trails, including text, photos, audio, video, (X)HTML and Flash, either via upload or by pulling them in from external sources such as Flickr, YouTube or Ourmedia.
Authors can publish their trails on the site, either publicly or to a closed user group, and optionally choosing from a range of licences that promote sharing, including Creative Commons and Creative Archive.
The map based interface currently uses Google Maps but support is also planned for our own map server offering a wider range of licensing options, including open (CC-licensed) map data for the UK from Richard Fairhurst of Système D (http://systemed.net/) and http://geowiki.com/.
We have purposely adopted a simplified authoring model, which avoids forcing the user to deal with complex interaction logic and event handling by providing a simple onenter and onexit trigger for each waypoint.
The site will also include tools for finding, joining or starting special interest groups. Groups can be public (open) or private (invite only) and include a discussion forum, the ability to share trails within the group and even to author trails collaboratively.
Handheld client
The handheld client is a custom mediascape browser (built on the Dot Net Compact Framework) which uses GPS signals to automatically trigger the playback of mediascapes in situ as the user follows a trail. This gives the richest user experience.
We aim for graceful degradation. If the user has a GPS enabled handheld running the Sharing Places client software they can download a trail and experience it in its full interactive glory.
If they have a ‘dumb’ GPS unit they can still download a trail and load it onto the device because we use the open standard file format GPX, with extensions that will be ignored if not supported.
If the user doesn’t have a GPS enabled device at all they can print an annotated route map and, in the case of trails with audio annotation, download the commentary separately for playback on an iPod, mp3 capable mobile phone or similar device.
A list of the trails which you have tagged on the website is downloaded to the client via the API on start-up. From the listing on the client you can choose which trails to download and cache locally for playback in the field.
Open API
The webapp presents an XML based RESTful API to the handheld client to present listings of trails (in response to searches) and to transfer complete trails and their associated resources for offline viewing.
The file format for mediascapes is based on and compatible with the GPX open standard [GPX]. It uses the extension mechanisms to define mediascape behaviour in a separate namespace meaning that ‘dumb’ GPS software can simply ignore the extensions. The extended format is entirely open, freely available and documented on the website.
We hope that it will become a common open format for located media authoring.
In addition to the XML API there is a JSON API used internally by the webapp for communication between the Ajax enabled map interface and the Django powered back end. This API too is publicly available and documented on the website.
We have adopted a RESTful design throughout the app, with human readable, hackable URLs such as http://sharing-places.com/trails/by/petef/ and http://sharing-places.com/trails/tagged/psychogeography/.
We also support relevant microformats (http://microformats.org/about/) where appropriate, such as hCard (http://microformats.org/wiki/hcard) for user profiles.
If you are interested in developing to the Sharing Places API you can sign up for a developer key on the website, or drop us an email.
What’s exciting
Paths not points
A central idea in human culture is the journey. A journey is a fundamental way in which we relate to space. We move from one place to another in a linear sequence. The idea of the journey is central to our myths and stories, it is encoded in our architecture and implied in our built environment, the streets outside our houses, the paths through the woods, the networks of freeways, the railway tracks through our towns, the airports on the outskirts of every city, the ports distributed along every coast. — Headmap Manifesto, [Russell]
Rather than just sticking pins in maps we are reinventing the songline for the 21st century. Mapping and sharing not just practical, navigational routes but the trails we discover (or create) through ‘drifting’ and playful exploration. Trails which can form the basis of narratives which we can share with and receive from other people.
Progressive enhancement & graceful degradation
Progressive enhancement & graceful degradation are becoming well established best practice on the Web [Champeon, 2003]. We think the same principles should be applied to located experiences whether online or offline.
Not having a specific piece of technology, or simply not having it with you, shouldn’t preclude your enjoyment of a mediascape. By delivering located content in a range of media from printed paper and simple audio, through to geotagged data for locative browser software, it’s possible to open it up to a wider range of people and to a wider portion of people’s lives.
Permeable membranes
Much of what we have built is based on open source software (Python, Django, Prototype etc.) and open standards for data (GPX, XHTML, microformats). We want the Sharing Places application to play an active part in the ‘Web of data’. We want data to flow into and out of the application as it ebbs and flows around the web.
To this end we are tying in to existing APIs, to allow users to access their own data (and other people’s if suitably licensed) from other Web 2.0 services — and we are providing an API into Sharing Places to enable users to get their data out and to facilitate working with mediascapes in their own applications.
We also like to reflect the open ethos by making it easy for people using our tools to license their work using open licensing regimes such as Creative Commons.
All of the client side Javascript code and the extensions to the GPX file format to support playback of mediascapes which have been developed as part of Sharing Places will be released back to the development community under one or more open source or Creative Commons licences.
Where next?
We have a range of plans to improve Sharing Places and to turn it into an epitome of a Web 2.0 service. In addition, we plan to augment the open and free service with facilities targeted specifically at professional content owners and publishers.
A key area of development is to support and encourage communities of interest to develop. Such communities could contribute detailed or collaborative views of places and would facilitate discussion centred on places.
On the implementation front, we clearly need to support a wider range of mapping sources, and this will be an early priority. We will also extend the range of supported client devices to include most popular GPS devices as well as migration onto mobile telephony platforms.
We will also produce a rich range of authoring and publishing templates to allow easy construction and dissemination of the most common forms of mediascapes — for example guided tours and treasure hunts.
As the mobile web becomes pervasive, the line between the authoring environment (on the web) and the located environment (on a client device in the field) becomes blurred. This raises several exciting possibilities. For example, the ability to do in situ authoring. This will allow photos and other media to be captured in the field, tagged with location metadata, and uploaded and added to a mediascape.
This promises a broader class of mobile social software that extends the direct interaction of a simple “are any of my friends here?”, supported by services such as [Dodgeball]. For example, a sort of “souped-up” situated blogging that uses stigmery (see http://en.wikipedia.org/wiki/Stigmergy) would allow interaction with other (mobile) users mediated by mediascapes generated on-the-fly for a specific group or individual audience.
We encourage you to play and experiment with our new service.
Bibliography
[Cater et al., 2005] Cater, K., Fleuriot, C., Hull, R. & Reid, J. (2005) Location Aware Interactive Applications. ACM SIGGRAPH 2005, Conference Abstracts and Applications. ACM.
[Champeon, 2003] Champeon, S. (2003) Progressive Enhancement and the Future of Web Design http://webmonkey.com/webmonkey/03/21/index3a.html
[Dodgeball] Dodgeball A web service that allows users to broadcast their location to groups of friends http://www.dodgeball.com/
[GPX] GPX The GPS Exchange Format http://www.topografix.com/gpx.asp
[Hull et al., 2004] Hull, R., Clayton, B. & Melamad, T. (2004) Rapid Authoring of Mediascapes. UbiComp 2004, The Sixth International Conference on Ubiquitous Computing. Nottingham, England.
[Reid et al., 2005] Reid, J., Hull, R., Cater, K. & Fleuriot, C. (2005) Magic Moments in Situated Mediascapes. ACM SIGCHI International Conference on Advances in Computer Entertainment Technology ACE 2005. ACM.