Using viewsheds, GIS, and a landscape classification to tag landscape photographs

Landscape scenery is inherently difficult to conceptualize because of its perceptual nature. Yet landscapes are an extremely important resource for tourism and quality of life so there is a need to classify and manage landscapes. This paper shows how viewshed analysis based on the known location and direction of a photo can be used to tag a photo and this provides a method for assessing the New Zealand Landscape Classification. GIS visibility and overlay functions are combined with digital elevation data and a landscape classification to produce the tagged photos. This tool links an oblique view with multiple distance perspectives to a GIS dataset. There are complexities associated with distance perspectives and the appropriate balance of foreground and distant landscape. This paper argues that the benefits of automated tagging of landscape photos are threefold. The process of modelling landscape tags forces researchers to confront the complexity of landscape character classification. This in turn leads to improved methods for representing and classifying landscape character. Secondly, once tagging methods have been developed then people may choose to use these tools rather than to manually tag photos. Thirdly, such a tool provides the opportunity to utilize the increasingly important volunteered geographic information on the Internet for understanding landscape categories. Landscape photographs and associated tags on the Internet provide insight about landscape categories employed by the public. This could lead to the development of what is labelled “tag clouds” and a landscape “folksonomy”.

► This paper demonstrates how viewshed analysis can be used to tag a photo.
► For assessing the New Zealand Landscape Classification.
► Engaging with the volunteered geographic information on the Internet.
► Developing “tag clouds” and a landscape “folksonomy”.