Keywords : Remotely Sensed


Design an Active Method to Calculate the Areas From Remotely Sensed Data by Using Image Processing and Geographical Information System

Khansa A. Ahmed; Sabah H. Ali; Rayan Gh. Thanoon

Iraqi National Journal of Earth Sciences, 2009, Volume 9, Issue 1, Pages 21-34

Recently, Satellite images became an important tools which were used in many cases of the practical studies, it has provide a widely view to the land covers and the ability to extract the information by applying the image processing technique on the images. The ability to detect the area of land covers from satellites images is very complex method because it is not only required a high geometrical satellite images but it needs to isolate each class from the classified image dependently from the another classes that viewed in the adopted image satellite. This process is very important to determine the area for each class with an accepted level of accuracy.
In the present study, an active method was design to extract and determine the areas by using digital image processing operations (digital filtering, geometrical registration and supervised classification). Landsat Thematic Mapper (TM) satellite image, which covered the study area (Mosul Dam Lake), was adopted as a remote sensing data set for the processing stages. Geographical Information System (GIS) software was applied for the georeferencing process of the TM satellite image (according to UTM-WGS84-38N System) with respect to the georeferencing topographic map of the Mosul Dam.
The result of the applied method was compared with result obtained from the GIS software, Global Mapper 9.2 (GM9.2) for the same study area, and then the output results of the two methods were compared to the traditional method to calculate the area of the class from topographic maps according to their complete and missing squares. A relatively good coincidence between the result of the present study and the other methods. The results and the applied technique of this research are very important in the practical applications related to the field of survey engineering, environmental studies (desertification and environmental pollution), forest, urban planning, geology…etc.
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Removal of Non-Systematic Noise From Remotely Sensed Databy Using Composed Filters

Abeer A. Al-Alaaf; Rayan Gh. Al-Banaa

Iraqi National Journal of Earth Sciences, 2007, Volume 7, Issue 1, Pages 1-12

Remotely sensed data especially satellite images contain noise in some cases for both types systematic and non-systematic. These noise represent by forms working to create problems in interpretation and analysis of remote sensing data. The non-systematic noise considered one of these problems because it appears by an random points in all parts of images and with different intensity of it surrounding areas. Therefore, the Non-systematic noise must be use active processing software to remove it, in order to avoid the effect on the other pixels which are not contain noise in the image. Oppositely, the systematic noise is shown by systematic frequently lines patterns, therefore it can been recognize and processing.
The present study shows an active method for removing the non-systematic noise without change the other pixels. The suggested method is represented by a design of decision function depending on mixed filter, which is formed by merging the median filter and average filter depending on the thresholds value which used in comparism.
The suggested method provided a good accuracy comparing with the classical methods, by removing the non-systematic noise without any pixel distortions of the original image.