Orthorectification is the process of geometrically correcting imagery for geometric
distortions which can be caused by topography, camera geometry, and sensor related
errors. The output of orthorectification has the same geometric characteristics o
f a
traditional map. But getting areal or satellite images is an expensive process requiring
complex administrative procedures .
In this study we propose take advantage of free images available in the browser
Google Earth in order to produce an orthophoto. Then we will assess the horizontal
accuracy of the resulted orthophoto to know the limitations of its use engineering
applications such as maps production and updating. The proposed methodology is based on
the flight simulation process within Google Earth to acquire a stereoscopic pair of
overlapping images. After that, this pair will be oriented using control points. The oriented
pair is then used to generate a Digital Terrain Model (DTM) and to generate the
orthophoto. Later, we will examine the accuracy of this orthophoto by comparing it with a
topographic plane (scale 1/1000) and with a rectified satellite image of the same area.
The importance of research lies in the need to keep pace with the technological development of computer systems and technologies
Modern methods, especially geographic information systems, in collecting, storing, analyzing and exiting
Spatial inform
ation and linking it to metadata, modeling and scenarios
Planners and decision-makers to assist them in planning and finding appropriate solutions for various problems.
