Evaluation of the capabilities of satellite images alsat 2-a for emergency mapping in urban areas, case of the city of m’sila (Algeria)

In this paper, we will show the capabilities and limitations of Alsat-2 images in mapping urban areas in emergency situation. The aim of the research was to provide urban information that is geo-referenced in real time during natural disasters (floods, earthquakes). It’s important for fast decision-making so that they will be a necessary support for the estimation of the damages. The following study tests the spatial and radiometric quality of Alsat 2-A images and proposes technical solutions for theiruse in urban mapping. In order to identify and extract the ground realities, we shall describe and make an effort to discern the perceptible aspects of features in urban area. The adopted methodology carries out a statistical analysis of the information extracted from Alsat-2 images of the studied area (the city of M’Sila, Algeria) using classification and segmentation methods. The statistics will show the percentage of the area in relation to the total size of geometric surface and the distance for linear objects. As a result, the quality of the extracted urban texture necessary for urban mapping will be determined. Image processing to improve resolution quality was carried out using merging method. However, the analysis of consistency and discrepancy of these statistics will be done by comparing samples of field data using confusion matrix.