A software program for semi-automated measurement of building façades

The dimensions of façades and window openings in buildings are usually determined by direct measurements using tapes and plummets. In this paper, we present a semi-automated application that makes it possible to obtain building measurements by means of an indirect method based on close-range photogrammetry. This application is intended to be used with a single planar-surface measuring system that permits measurements to be made without contact with the building. This system combines the output from a digital off-the-shelf camera and a laser distance meter. These data are used within our application for image orientation and scaling. Next, the software permits calculation of the dimensions of elements on the planar façade and also provides an estimate for the precision of those dimensions. This indirect approach avoids time-consuming and risky procedures in building measurement and permits the user to take inventory of a building under construction.