Maps are fast and accurate information sources when it is required, to
study and to develop projects in any region. In Egypt, many of the
available maps are in an unsatisfactory scale and not updated. The
availability of Egypt Sat1 satellite images, opened new possibilities for
mapping and map updating. Egypt Sat1 is the first Egyptian earth
observation satellite which was successfully put in orbit in 2007. It
captures both multi-spectral and panchromatic images with resolution of
7.8 meters. The main objective of this study is to evaluate the potentials
of information content in Egypt Sat1 images for extracting features in
the context of updating of 1:25,000 topographic maps and to ascertain
what features could be identified and mapped using visual interpretation
techniques supported by supplementary data.
Data used in this study are an image from Egypt Sat1satellite captured
in 2009 and a topographic map, dated 1991, at scale 1:25,000 of the
region of Assiut city and the surrounding. The investigation in Egypt
Sat1 data focused on identification of urban features such as roads,
railways, watercourses, bridges and boundaries of urban areas. ERDAS
imagine 9.2 software was utilized, where qualitative and quantitative
evaluations were performed for the informative content. The research
results point to the potential of Egypt Sat1 images as a low cost
alternative data source with field verification for the updating of
topographic maps at scale 1:25,000.