Information Extraction(Remote Sensing and Image Analysis) Essay

Information Extraction(Remote Sensing and Image Analysis) - Essay Example rget, in which the spatial arrangement is preserved); techniques involve amassing knowledge pertinent to the sensed scene (target) by utilizing electromagnetic radiation, force fields, or acoustic energy sensed by recording cameras, radiometers and scanners, lasers, radio frequency receivers, radar systems, sonar, thermal devices, sound detectors, seismographs, magnetometers, gravimeters, scintilla meters, and other instruments(The Concept of Remote Sensing) Remote sensing is mostly used to study objects or a particular area on earth using the photographs taken by the remote satellites stationed above the earth. Microwave signals are using in such process because of these wave’s ability to penetrate clouds fog and rain. ‘The atmosphere has a big influence in satellite and high altitude aerial remote sensing.’ (Robert A. Schowengerdt p.48) Because of the scattering property of light by atmosphere the image obtained through remote sensing may not be clear. ‘Variations in platform altitude, velocity, and attitude variations in the elevation or altitude of a remote sensing platform lead to a scale change and field of view’. (John A. Richards, Xiuping Jia –p. 43.) Remote sensing image data normally require two or more scenes of the same geographical region acquire at different dates to be processed together for many applications. This is because of the complexity in analyzing the image because of the too many obscured pixels in it. Most of the remote sensing image data is too low in brightness and poor in contrast. In order to improve the quality of the image automatic contrast enhancement technology is used. Remote sensing images are usually two dimensional. The images obtained through remote sensing analyzed through the study of the number and location of spectral measurements or spectral bands. The spectral measurement in each band depend on the interactions between the incident radiation and the atomic and molecular structures of the material (pure