Power lines are subject to damages caused by atrocious weather and surrounding objects such as big branches of trees. To prevent an accident

costly on-the-spot routine inspection and maintenance have to be made frequently. Therefore

it is significant to build an early alerting system to improve the efficiency and decrease expenditure. An efficient alerting model is presented based on a digital surface model (DSM)

which is generated from multi-angle remote sensing images

power line towers and spacers are identified to fit the power line as a parabola

and the shortest distance between DSM pixels and power line is calculated and defined as the alerting index. An HDF data format is developed to store the alerting data

which provides powerful support to perform fast views through the built-in raster pyramid of the alerting maps. Three approaches are adopted to view the maps

namely

the alerting classes map

the fusion map of the alerting classes map and other images

and the pseudo-color alerting map. The code of the alerting model is integrated in the airborne multi-angle power line inspection system (AMPLI).