Positional Accuracy of Flickr and Panoramio Images in Europe

Flickr and Panoramio are fast growing photo sharing services that provide a rich resource of Volunteered Geographic Information through geotagged images. This study analyzes the positional accuracy of 211 image footprints for six cities in Europe by comparing the geotagged position of photos to the position from where the photos were most likely taken, based on the image content. The analysis reveals a better positional accuracy for Panoramio than for Flickr datasets. For Flickr data, some associations were observed between the category of photographed scene and positional accuracy, while this was not the case for Panoramio images. The accuracies identified in this study can be helpful when considering Flickr and Panoramio images as data source in future geo-applications and services.