The de’ Barbari map is a woodcut aerial view of Venice (see Figure 1) created by Jacopo de’ Barbari in the year 1500. The map is impressive not only due to its large dimensions, but also because of the meticulous attention to detail, as shown in Figure 2. Indeed, we can distinguish almost every house on the map, making it a very valuable historical document to study the architecture and the structure of the city at the very beginning of the 16th century.
Studies of the different architectural details have been done extensively by different authors , our task was to label and annotate the most important features on the map using digital tools provided by the DHLab. These annotations should be easily accessible and searchable on the online platform, enabling researchers to link different historical sources together. Additionally, we have experimented with extending our labelling to other sources in order to compare the features of the de’ Barbari map with its contemporary counterparts.
Background research and pre-labeling
Before labeling and annotation was done in the DHCanvas, it was necessary to gather information and do background research to correctly identify landmarks. The first step of this preparatory work was to obtain print copies of the de’ Barbari map for pre-labeling. Major landmarks such as churches, bell towers were easily recognizable and were identified first. Different resources [1-4] were consulted for further identification.
At this point, it is worth noticing that some of the projects and resources that we consulted have had similar objectives. The first project  is a crowdsourcing initiative started by Jonathan Gross. The final goal of this project is to label all 103 bell towers on the de’ Barbari map. As of now, relatively few towers have been identified; but this project will undoubtedly provide some new information and will also serves as an interesting example of the potential for the crowdsourcing of information within the context of our project. The second project is one helmed by The Venice Project Center , of the Worcester Polytechnic Institute. They have created a searchable de’ Barbari map, although numerous elements remain unnamed or are named incorrectly. This map shows the precise locations of demolished churches, as well as those that still stand, or have since been repurposed, bridges, islands, bell towers, canals, convents, fields, well heads, and mountains. Each of these features are stored in a vector format and some can even be referenced on other maps—for example Ludovici Ughi’s map of Venice from 1729. Finally, we also referred to works from a Columbia University project called Mapping the Art & Architecture of Renaissance Venice . This project has built an interactive map de’ Barbari map, where many important features such as churches, palazzi, scuole, public buildings and spaces and modern structures have been identified. However, the main distinction between these initiatives and our project is that the information added in our virtual map will be included in searchable database allowing us to create links between old venetian documents and historical places on the de’ Barbari map.
Annotation on the DHCanvas
After the preparatory step was completed, we transferred the labels and annotations onto a digital copy of the de’ Barbari map on the DHCanvas platform. As shown in Figure 3, one can draw out rectangles, or segments, to highlight features on the map. Using these segments to identify features, information could be added in a dialog box. In addition to naming features, tags were also added in order to classify the different landmarks. The tags used in our project included Neighbourhood, Church, Convent/Monastery, Bell Tower, Palazzi, Canal and Bridge. These annotations could be then retrieved by performing a simple search using the DHCanvas search engine, that covers the whole Venice Time Machine database.
Annotation of other resources
We also extended this labeling and annotation to a modern map of Venice. More specifically, we created ESRI vector shapefiles identifying the location of the labeled features of the de’ Barbari map on a modern map of Venice. Each feature type (e.g. neighborhood or church) has its own vector shapefile that contains all the features of that type present on the de’ Barbari map. This process was interesting as it revealed the geographical and technical inaccuracies present in the de’ Barbari map due to limitations faced during creation of the original map in the 1500s. For example, the east of Venice as represented on the de’ Barbari is much more horizontally stretched out than it actually is. This could shed light on how people in the 1500s perceived and gave importance to the built environment of Venice. Additionally, these resources eventually could be used to study the evolution of the built environment from 1500 to present.
After all labeling and annotation was completed on the DHCanvas, we tested the DHCanvas search engine with various search terms relevant to Venice and its built environment. The results obtained were inline with our expectations: for any given search term, we obtained all results from the DHCanvas platform that were named or tagged with the search term. These results included the labeled segment of the de’ Barbari map as annotated over the course of this project, as well as other relevant documents such as historical transcripts and texts. An illustration of these search results are shown in Figure 4.
One limitation we encountered while using the DHCanvas annotation tool was its lack of versatility. At present, only rectangular segments are available for annotation purposes. While rectangular segments may be relatively accurate for small features such as churches and bell towers, it does not accurately demarcate other bigger and more complex features such as neighborhoods and canals. As a result, searching for a canal using the DHCanvas search engine may return results that are not easily discernable. Another limitation to the tools success is related to its inflexibility with regards to the naming of entities. For example, typing “S. Marco” into the search engine brings up entirely different results than “San Marco”; such a limitation could become quite significant as more and more annotated documents are includeed in the database.
CONCLUSION & FUTURE PERSPECTIVES
This project is a preliminary step towards creating a fully searchable map and spatially linked historical database. Future work will focus on labeling many of the less significant features that were not identified in this work; perhaps by extending labeling to specific addresses or house numbers. Additionally, these annotations could be more integrated with the other elements of the DHCanvas and Venice Time Machine. For example, direct hyperlinks can be created between the annotated features of the de’ Barbari map and other historical documents. Also, as the shapefiles created in this project are geospatially representative, they can be exported as KML files for comparison purposes in Google Earth. The shapefiles can also be useful in extending the annotation process to other maps both within and beyond the DHCanvas. The labeling of other historical maps of Venice allows the study of the spatial evolution of Venice over time.
All in all, while tedious and labor-intensive, the annotation of historical maps and documents, such as in this project, is important in kickstarting the process of creating links between the different aspects of society at any given period of time. Only when we consider all aspects of society and study them in an integrated manner, can we better understand how it was, how it has evolved, and gain new insights and perspectives.
 Balistreri-Trincanato, C. et al. Venezia città mirabile: guida alla veduta prospettica di Jacopo de’ Barbari. Cierre, 2009.
 Gross, J. Help Find All 103 Bell Towers In This 500 Year-Old Map Of Venice, Italy. http://gigapan.com/gigapans/166926. 2014. Web. 7 Mar. 2016.
 Venice Project Center. Venetian Historical Map Explorer. http://cartography.veniceprojectcenter.org, 2013. Web. 7 Mar. 2016.
 Rossand, D., et al. Mapping Art and Architecture in Venice. http://learn.columbia.edu/venice/. 2007. Web. 9 Mar. 2016.