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Location-aware Mobile Devices and Landscape Reading

Ruben JOYE, Joris VERBEKEN, Steven HEYDE and Harlind LIBBRECHT

Abstract This paper examines how ‘smartphones’ – a type of advanced and location-aware mobile phone (e.g. Apple iPhone® or phones running Google Android®) – can be useful for landscape architecture and planning, and more specifically how they can share knowledge about our surroundings using ‘Mobile Augmented Reality’ (MAR). We examined how a smartphone-based information system can influence reading and understanding the landscape, and to what degree it influences landscape valuation and imaging by its users. A quantitative survey was conducted with students to determine the educational possibilities of such tool. The main part of this paper however, is more technical in nature. Using the ‘Layar® Reality Browser’ as a framework for our MAR, we wanted to facilitate the management of a ‘Layar® 3D’ system. We did so by building a graphical front-end to the administrative part of the system by using a combination of ESRI ArcGIS® and Microsoft Access®. This to facilitate adding, editing or removing ‘Points Of Interest’ (POI), even to people with a limited technical background..

1 Introduction

With smartphones (e.g. Apple iPhone® or phones running Google Android®) becoming more popular every month, in the third quarter of 2010 accounting worldwide for 19,3% of overall mobile phone sales compared to 9,85% in 2009 (COZZA et al. 2010, GARTNER 2010), it’s safe to conclude that location-aware mobile devices are getting more and more widespread. These types of devices – equipped with both GPS technology and mobile internet connectivity – are taking GIS information mobile, making it possible to associate digital media to a geographical location (VARNELIS & FRIEDBERG 2008). Handheld location-aware mobile devices are becoming the interface to the ‘geospatial Web’, that delivers on the spot georeferenced information to its users. This allows people to be present in both the physical and networked (digital) place (ITO 2008). 2008 – the year in which for the first time in history, mobile access to the internet exceeded desktop computer-based access (ITU 2009) – turned out to be the start of an internet revolution, quickly named ‘the mobile web’. An interesting application for these location-aware devices is ‘Mobile Augmented Reality’ (MAR): the superpositioning of rich media elements (audio, video, images and even 3D-models) on top of a real-time view from the built in camera lens of the portable device. The technical aspect of a MAR-system has already been considered by JOYE et al. (2010) and the opportunities for education in landscape architecture have been discussed by VERBEKEN et al. (2010).

R. Joye, J. Verbeken, S. Heyde and H. Libbrecht

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A prebuilt and free client-application called ‘Layar® Reality Browser’ is available for both the Apple iPhone® and phones running Google Android®. One of the harder parts is setting up your own Layar® POI server that communicates with the Layar® client on the smartphone. Luckily there are a few different development tools available online (CAMERON 2010), with PorPOISe (DE SMIT 2010) – a PHP based POI-server – being one of the most comprehensive. Some adjustment to the programming code is needed, in order to have it connect to the record with the POI’s you want to show. This can either be an XML formatted file, or a MySQL® relational database.

PorPOISe (version 1.0a was used) comes prebuilt with a textual web interface called ‘PorPOISe server dashboard’ (Fig. 1) that allows authorized persons with no program-ming skills to add new ‘points of interest’ (POI’s). However, when you’re planning to have numerous POI’s, this can be cumbersome since you need to look up (and enter) the lat- lon-coordinates for each POI manually.

One of the main reasons for fractional use of landscape visualization tools (in general) – according to BISHOP & LANGE (2005) – is the lack of user-friendliness for easy manipulation (BISHOP & LANGE 2005). It was our intention to meet this constraint by improving the usability, by linking the underlying MySQL® database with ESRI Arcmap. A new POI can be added

Fig. 1: Web interface of the ‘PorPOISe server dashboard’

more easily by use of and at the same time it becomes possible to import both the spatial as well as the attribute data of already existing GIS-datasets (e.g. ESRI shapefiles). It appears we are not alone in seeing great value in a tighter integration of GIS-data in the Layar® Reality Browser. A similar idea was carried out by EMGE & PRASAD (2010). Details on their approach are missing though.

The need for a better way to manage POI’s arose from the fact that an arrow-less GPS-based touristic route will be created at the end of our landscape research project. In order to evaluate our new workflow involving ESRI ArcMap, we’ve put together a small test case. As part of the research project – which studies change in a former World War One region – a pilot study on the subject of landscape evaluation has just been completed in close cooperation with historians from the ‘Memorial Museum Passchendaele 1917’ (MMP) and the Flemish heritage institute (BOSTYN et al. 2010). This preparatory research work served as a base for the landscape walk.


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The second part of the paper will focus on how location based information can influence landscape perception and -valuation. During the process of mental imaging, the observer interprets the perceived landscape. Therefore, individual landscape valuation is not only contextual and time bound, but also strongly personal or subjective (JACOBS 2006) since the plethora of visual stimuli gets filtered, before final imaging takes place. Unconsciously, a selection of stimuli is performed in terms of usefulness for the given situation, partially based on prior knowledge (cognitive aspects) (DIJKSTRA & KLIJN 1992). For instance – in the case of cultural heritage landscape valuation – an observer with little to no knowledge about the landscape and cultural heritage will be able – at best – to distinguish the main landscape structures, but will overlook more detailed information (COETERIER 1995, VAN Den BERG & CASIMIR 2002). As landscape experience and –valuation is much more than just an aesthetic consideration (DIJKSTRA & KLIJN 1992), this detailed information may have a strong influence on one’s final assessment of the whole. By pointing the observer’s attention to these details (e.g. cultural remnants), as well as providing background information (e.g. about historic events that took place), the appreciation of landscape experience will be more balanced, more strongly founded, and surpass a purely aesthetic appraisal.

A quantitative survey, was carried out with a group of 20 students enrolled in a one-year advanced study in landscape development. They gave their opinion on both the ease of use of the smartphone system, the educational possibilities, as well as their impressions of the physical environment and how it had changed their appraisal and overall assessment.

2 Material & Methods

2.1 Technical

After installing the ODBC MySQL® Connector (version 5.1.8. was used), linking a shapefile to a MySQL® database is easily feasible from within ArcGIS, using ESRI ArcCatalog to setup a 'database connection' by means of an 'OLE DB Connection'. The additional columns and corresponding values that are stored in the external MySQL® database get added to the attribute table in ArcMap without any problems. But the drawback is that this external database cannot be edited from within ArcMap (as this is a read-only process), making this approach useless for our stated goal. To overcome this problem, an intermediate step was taken that at the same time adds functionality to the workflow. A Microsoft Access® form linked to the main POI shapefile was created, in which all the necessary data about each of the POI's can easily be entered.

This was done by making use of the ArcScript ‘ArcMap Hyperlink to Filtered Microsoft Access® Form’ provided by CALLAHAN & CARSON (2003) on the ESRI support page. This filters all of the entries in order to show only the corresponding data in a clear Access form (Fig. 1). Although programmed to work in conjunction with ArcGIS 8.2 and Microsoft Access® 2000, this script works just fine using ESRI ArcGIS 9.3.1 and the newer versions of Microsoft Access® (both 2007 and 2010 have been tested).

The use of this script requires working with a personal geodatabase, which can be created in ESRI ArcCatalog. Once we have a personal geodatabase set up, we add a new (point) feature class which we name ‘POI’. As coordinate system ‘WGS 1984’ – the international


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standard for use in cartography, geodesy, and navigation – is chosen. The resulting feature class has two mandatory fields: ‘OBJECTID’ and ‘SHAPE’. We add an extra field ‘accessid’ (text) which will mirror ‘OBJECTID’, but is necessary to link with our Microsoft Access® form since the ArcScript requires the data type of the field to be a text value.

A minimal MySQL® database for use with PorPOISe – that enables basic Layar® functionality – consists of one table named ‘POI’ with the under mentioned structure. Note that in the overview schema (Fig. 2) we added the three fields necessary for use with ArcGIS (indicated by an asterix), but that these do not negatively influence the functioning of either PorPOISe or Layar®.

POI id attribution imageURL lat lon line2 line3 line4 title type doNotIndex showSmallBiw showBiwOnClick layerID dimension alt relativeAlt SHAPE(*) OBJECTID(*) accesid(*)

Action id uri label poiId contentType method activityType params closeBiw showActivity activityMessage autoTriggerRange autoTriggerOnly

Object poiId baseURL full reduced icon size

Transform angle rel scale poiID

Layer layer refreshInterval refreshDistance fullRefresh showMessage id

Fig. 2: Overview of PorPOISe database schema with the five tables making the structure for use with Layar® (*) = added for use in conjunction with ArcGIS

If you want to make use of more advanced features in Layar® like 2D/3D objects and actions, you need to add additional information to the POI’s: what is the URL to the 3D-model, should it be scaled, rotated, … Are there actions connected to the POI like a link to an external webpage, audio, video and should these trigger automatically or not? All this information gets stored in three tables separate from the POI table. A fourth additional table was introduced to support the Layar® v4 API features (DE SMIT 2010), totaling five tables: ‘POI’, ‘Object’, ‘Transform’, ‘Action’ and ‘Layer’. This last table isn’t of much interest to us, and can be left blank to have the Layar®-client use the default values.

The functionality of each of these fields has already been discussed in detail by (DE SMIT 2010, WANG 2010, WANG 2011) and therefore is not repeated in this paper. Albeit, the meaning of each field was included in the final version of our Microsoft Access® form as a tooltip displayed when the mouse hovers over a field.


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Fig. 3: The Microsoft Access® form linked to the ESRI Arcmap document. This form combines data from five different tables and constitutes the MySQL® database which PorPOISe uses to serve to the Layar® client-application.

To get the proper database schema for all the required tables, a SQL script file 'database.sql' comes with PorPOISe. This file was executed to our external MySQL®-server using the MySQL® Workbench (version 5.2.31a) which easily created all the proper tables and data types settings for the different fields. Having already installed the ODBC MySQL® Connector, we were also able to connect to our MySQL®-server using Microsoft Access®, and have the database schema imported to our personal geodatabase (opened as a Microsoft Access® document). The first thing we need to do for it to work, is to add a new connection by using the Microsoft ODBC Data Source Administrator which can be found in the ‘control panel’ under ‘administrative tools’. Once this connection has been added under the ‘file-DSN’ tab, it will become available in Microsoft Access®. With our personal geodatabase opened in Microsoft Access, we chose ‘external data’ and picked ‘ODBC-database’. This allows to import the database schema, and have a functional database in accordance with the PorPOISe structure. The process of importing a MySQL® database in Microsoft Access® is described more in depth in a ‘White Paper’ from SUN MICRO-SYSTEMS (2009). After defining the relations between the different tables, and executing the query, a Microsoft Access® form was created (Fig. 3).

2.2 Content & use

To put this workflow into practice, a small quantitative survey was conducted. Not only to test the ease of use, but at the same time to evaluate the influence of location based


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information on landscape perception and valuation. The chosen area for our test case, is an old castle park which has undergone complete destruction during the First World War. Now the castle park serves a public function as a museum. In future developments this will be the starting point of a complete landscape route using a smartphone application. We chose a total of 39 historical photos and drawings (Fig. 4-7) that accurately depict the gradual decay of the beautiful center of ‘Zonnebeke’ (near Ypres) as it underwent successive bombardments and ruthless attacks.

Fig. 4: Soldiers rowing in the pond, withthe former castle and church in thebackground (1915-1916) © MMP 1917

Fig. 5: The original castle and ancient church, in the foreground the pond with bridge (1915-1916) © MMP 1917

Fig. 6: The church and the park showheavy traces of destruction (1915-1916) © MMP 1917

Fig. 7: The devastated region surrounding the castle park (near the end of 1917) © MMP 1917

A group of twenty students (on average aged 22) was taken on a 20 minute walk in the park. As stated in the introduction, these were students enrolled in a one-year advanced study in landscape development, most of them being graduated landscape architects. Of the twelve students who filled out the survey, the male-female ratio was exactly half-half. This quantitative survey looked at not only the ease of use of the smartphone system, but more particularly if and how the use of this system influenced their landscape valuation. While it does give a good insight in their experiences, drawing hard conclusions based on these twelve respondents would be imprudent. On top of that, weather conditions that day where quit harsh: cold winds and rain resulted in smudgy trails. Much to our surprise, none of the


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students present had a compatible phone. As a consequence, only two smartphones were available to be shared with the entire group.

The survey itself consisted of twenty-two questions divided into three categories:

their mobile phone habits: which type of phone do they have, is there an intention to buy a smartphone, who pays for their phone, what is their budget,…

their general experiences on educational innovations: is technologic innovation key to good education, is there immediate educational use for the application,…

the actual use and experience of the system: was the user interface easy to use, has it changed your way of looking at your surroundings, do you value the area higher on a cultural-historical level, would you take a complete tour with the smartphone once finished,…

3 Results

3.1 Technical

With the personal geodatabase correctly set up as described in 2.1, we started off with a Blanc ArcMap document. The projection was set to our local geographic coordinate system (Belge Lambert 72), and a georeferenced aerial photo of the area was added. Next, the point feature class ‘POI’ from our personal geodatabase was added to the map. As this data source was set up for use in WGS 84, a system warning about the mismatch is shown. Transformation from WGS 84 to Belge Lambert 72 can be applied from ArcMap. The option to do so is available from within this warning message, where you can choose to have the feature class aligned properly without distortion of the aerial photo.

New POI's can be added by using the ‘Sketch tool’from the editor toolbar to create new features. After having added some new features, we need to update the attribute table. The auto increment values in the ‘objectid’ field need to be copied to both the ‘accesid’-field (for the ArcScript to function) and the ‘id’-field (for PorPOISe and Layar® to function). The field calculator can be used for this to have the values copied instantly. Contrary to ArcMap, Layar® needs to have the longitude and latitude values of each POI in the attribute table. Similar to the previous step, these values can be calculated, now using the ‘Calculate Geometry’ tool in the attribute table. Using ‘WGS 84’ as the coordinate system, the correct decimal degrees can be calculated for both the ‘lat’ and ‘lon’ field in the attribute table.

Once these fields have been populated, the hyperlink tool in the tools palette can be used to jump to the filtered form in Microsoft Access®. There, all the necessary information on each POI can be added or updated. Having the latitude and longitude position of each POI as values in the database, also results in being able to display a map with the location of the active POI from within the Microsoft Access® form (Fig. 3).

The final step in physically being able to access this information on a mobile device, is updating the MySQL®-database on our server. A free and easy way to do this, is by using a freeware tool called ‘Access To MySQL®’ by the company Bullzip. It’s as easy as selecting the tables in your personal geodatabase that you wish to transfer, entering your server connectivity credentials and hit ‘Run Now’. Commercial solutions for synchronizing a local database automatically are available as well (e.g. DBSync for Access and MySQL®).


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Finally, exporting the POI-information in the linked tables as an XML-file is a possibility as well. Attention needs to go to the fact that this needs to comply with the XML-structure set forward by PorPOISe, which requires some tweaking of the exported file.

3.2 Content & use

The Layar® client applications makes viewing the entries on the smartphone possible in three different ways: 3D-live view (Fig. 8), list view (Fig. 9), or on a map (Fig. 10).

Fig. 8: 3D-live view

Fig. 9: POI’s viewed in list mode Fig. 10: Map view As for the results of our quantitative survey it’s important to again emphasize that our sample of 20 students was on the small size, thereby not generating any true generalizable outcomes. The result of this quantitative survey should be interpreted as the opinion of a small group rather than an unambiguous conclusion.

A third of the respondents agreed that the limited size of the smartphone screen is a significant bottleneck to the system. The fact that we had only two devices which had to be passed around, might have contributed to this. Tablet pc’s like the Samsung® Galaxy TAB (running on Google Android® as well), can respond to this feeling of shortcoming, as they offer a greater immersive experience due to the significant larger screen size (MAARTEN 2010).


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Half of the respondents found that the location specific information they got through the system impacted their landscape perception. A third had no opinion, and two respondents disagreed. There was more consensus on the question whether or not it resulted in a higher valuation of the landscape in terms of cultural heritage, where ten out of twelve (83%) agreed.

Two thirds of the group felt that the augmented reality technology as it is now, is still too premature to have practical use in education. Their critical attitude is also reflected in a more general question about educational innovation. Half of them believes that using multimedia or technology doesn’t necessarily result in a better understanding of the learning content or helps them to keep focused.

Whereas three quarters thinks digitalization and technological innovation results in a bigger democratizing of education and knowledge gathering, one might question whether the threshold for obtaining the information does not increase, since it requires having a smartphone. Already 40% has a mobile data plan, but only a third has a smartphone. All of them running Symbian (Nokia’s mobile operating system), which at the time of our landscape walk was still unsupported by Layar®. Just recently the Layar® platform has been ported to the operating system Symbian, opening up augmented reality to be used on a selection of Nokia® smartphones (LAYAR 2011).

No more than 15% is prepared to pay upwards to €200 for a new mobile phone, the critical price for an entry level smartphone capable of running the Layar® reality browser. Following price (39%), their main concern is the design (28%) rather than more functional aspects like standby time (11%) or number of downloadable applications (17%). Until prices start to drop even more, it seems unlikely that the technology has chance of being adopted as an everyday tool by these students on short term.

We found no pronounced differences between the responses of male vs. female students when it comes to their landscape experience. A prominent differentiation we did find was that male students are willing to spend more money when buying a new mobile phone, but that they simply do so less often. None of the female students would spend more than €200 on a new phone, while a third of the male students indicate to be willing to pay over €200. Some of them even more than €500. All of the male students use their phones for at least two years, while two thirds of their female counterparts indicate getting a new phone around every year. Additionally the male students showed greater confidence in educational opportunities and believed more strongly that location aware information by means of mobile devices has greater impact when compared to a brochure or billboards.

An encouraging fact is that all of the respondents indicate that – once this system is further developed and contains more information about the larger region of Ypres – they would make use of this location based service in order to explore and learn more about the area.

4 Conclusions and Outlook

The images we placed in our database, were so called “2D billboard images”. They had a location, but in some cases students found it hard to tell in what direction the photo was taken. A way to achieve a higher user understanding would be to work with ‘experience


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domes’ in Layar®. These are large spheres (3D-models) that have a photo texture applied to the inner surface. Walking into one of these ‘virtual caves’ fills the entire screen, and depicts only the part of a larger panoramic image that corresponds with your current view direction. This makes it much easier for the user to connect the present with the virtual image. Since the images we had at our disposal were mostly regular photos with limited field of view, the results using the ‘virtual cave’ principle would have been poor. When it comes to visualizing future intervention however, this approach becomes of great value. As opposed to the limited number of polygons a 3D-model for use with Layar® may contain (JOYE et al. 2010), the level of complexity in the texture of a ‘virtual cave’ (or dome) is of no importance for the application.

Although the management of POI’s to be displayed in Layar® proved very functional, and could be integrated in familiar workflows (i.e. ESRI ArcGIS and Microsoft Access®), the initial setting up in order to have everything streamlined requires advanced computer knowledge that cannot be assumed from neither students nor landscape professionals.

The difference in geographic coordinate system between the aerial photo and the point feature class results in minor deviation. In the smartphone applications this inaccuracy is negligible, especially since the GPS-signal itself manifests higher imprecision.

The numb task of having to have the latitude and longitude values calculated in the attribute table, and copy values from one field to another field using the ‘field calculator’ before being able to switch to Microsoft Access, could be more automated. Ideally, these values should be updated automatically each time a new feature gets added (or an existing one modified).

Further research and development –conducted by programmers – would be extremely valuable in terms of making the entire process of creating a Layar® and adding POI’s even more intuitive and user-friendly. Looking deeper into ways of integrating different georeferenced data standards of different kinds by means of easy to use extensions to for instance ArcMap would be much appreciated. To that respect the recent announcement of what could develop into an open standard for augmented reality – based on a combination of HTML and KML – developed by Georgia Tech looks quit promising (CHRISTOPHER 2011).

Lastly, the effects of using location based services on smartphones in terms of landscape perception and –valuation should be studied more in depth. A larger test group is needed to draw more founded conclusions. In addition to that, comparing other influential parameters (e.g. having a local expert as a tour guide) with a smartphone application would be interesting.

Since learning to ‘read the landscape’ – a skill that in essence can only be acquired in the field – is an essential part of a landscape architect’s education, such system could be used to enrich landscape walks for students. In addition, this also allows students to repeat the walk individually at any time.


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