Analyzing urban history using Google Earth and Qgis (2/2)
In this video, we will quickly make high-resolution google earth underlays for all years. Analyzing historical images is easy with Google. Just go to View-View Historical Imagery. By comparing the data between the years, you can distinguish where new buildings appear. Also, the demolished buildings will show only in the older satellite images. We merge 4 google earth screenshots for each year. In Part 2, we will georeference the images and analyze the data using QGIS 2.18. You can use orthophoto images in google earth both for analyzing and digitizing. In this part, we will digitize the buildings by looking at the images. We take reference from the oldest map (from 2006) and use the buildings there as existing. Then, we compare the maps. If a building doesn't appear in the urban boundary, then we declare that "demolished" for the according time period. Analogically, if a new building appears, it is digitized as "newly built" for that time period. Programs used: Google Earth, QGIS 2.18Date: 20.01.2020