High resolution and automatic survey of buildings by IR thermography

The paper illustrates a new approach to achieve the temperature distribution of a buildings composing a global view, at high resolution. It starts from the state of the art and describes how to manage the thermograms content. The on line radiometric calibration of raw thermograms allows obtaining a high accuracy of temperature readings. The calibration is performed using a grid of special targets viewed by the thermographic camera. An accurate global view of the building envelope is produced with images of thousands per thousands pixels trough an automatic mosaic composition of thermograms. Advanced image processing, including the geometric correction is performed in real time. The final result is a 3D model of the building, georeferenced and with capability to perform heat flux measurements. In addition, IR images, Near IR and visible electromagnetic bands are fused for the building material evaluation. As case study, the exterior surface of Palazzo Ducale in Venice, is analyzed and illustrated.