Primena satelitskih snimaka za dopunu sadržaja topografskih karata / An application of satellite images for improving the content of topographic maps

Vojnotehnički Glasnik

Miodrag D. Regodić¹ 

[1] Univerzitet odbrane u Beogradu, Vojna akademija, Katedra prirodno-matematičkih i tehničkih nauka, Beograd;

关键词: topografska karta;    satelitska snimanja;    geografski elementi;    topographic map;    satellite surveys;    geographic elements;   

DOI  :  10.5937/vojtehg1004063R

来源: DOAJ

【 摘 要 】

Neažurnost sadržaja topografskih karata (TK), uslovljena ponajviše stvarnim ekonomskim teškoćama pri izradi novih i dopuni postojećih izdanja, kao i nedovoljnost i sve teže stanje pri izradi ostalih geotopografskih materijala (GTM), u velikoj meri otežavaju geotopografsko obezbeđenje (GTOb) vojske u miru, kao i u svim periodima pripreme i vođenja ratnih dejstava. Rešenje ovog problema je u iznalaženju adekvatnog načina upotrebe proizvoda svih vrsta daljinskih snimanja, a naročito u obradi kvalitetnih satelitskih snimaka. Kao najbolji pokazatelj velikih mogućnosti daljinske detekcije, korišćenjem satelitskih snimaka, u kartografskoj praksi primenom kvalitetnih softverskih rešenja, u radu je predstavljena dopuna topografske karte nedostajućim topografskim sadržajem. / Lack of updated content of topographic maps (TMs), mainly due to economic issues regarding the publishing of existing or revised TMs, substantially affects geo-topographic supply (GTS) of the Army both in peace and warfare time, as well as shortage of other geo-topographic materials (GTMs). The solution to this problem is in finding an appropriate method of using products of all types of remote sensing, high quality satellite images in particular. Having shown the best possibilities of remote sensing while using satellite images in mapping through the quality software solutions, the author presents an addition to topographic maps based on missing topographic data. Introduction Numerous natural and social phenomena are constantly observed, surveyed, registered and analyzed. Permanent or periodical satellite surveillance and recording for different purposes are growing in importance. The purposes can range from meteorological issues, through study of large water surfaces to military intelligence, etc. These recording can be used in making topographic, thematic and working maps as well as other geo-topographic material. Processing and analyzing of ikonos2 satellite images for complementing the content of topographic maps Images taken from aircraft and satellite platforms are very important sources of data for studying and presenting natural and artificial phenomena on the Earth. Understanding the links and relations between digital values of pixels recorded on sensors and the phenomena on a terrain enables a proper interpretation and analysis of an image. The subject of the experiment presented in this article is a satellite image of the Belgrade city area, made by the IKONOS 2 satellite of the European Space Imaging Company. It belongs to the GEO Ortho Kit products category, which means that it is approximately georeferenced and completely orthorectified. Georeferencing of an ikonos2 satellite image A procedure in which an image is taken into a desired coordinate system through orientation points (rectification), where the image is conveyed into a projection close to the orthogonal one, is called georeferencing (process of conveying an image into a reference coordinate system), while the level of geometric transformation is external geometrical transformation [5]. By georeferencing we establish certain mathematical dependence between the points on the image and the known points of the surveyed terrain. These points are called orientation points, control or GCP points (Ground Control Points). Procedures of digital image processing image pre-processing The biggest deficiency of satellite images that could be used in a digital form for making and maintaining working maps is a series of mistakes (deformations) of geometric mapping. These deformations that should be removed before further processing are viewed as: - A change of intensity of pixel grey tone caused by the characteristics of the surveyed terrain, object or phenomenon, and - A wrong relative position of a pixel in the image raster matrix. Image quality enhancement After removing deformations and taking image into a desired coordinate system, in further image processing, it is necessary to improve its quality and emphasize the date to be collected. The enhancement of image quality can be: - radiometric (radiometric enhancement) - contrast enhancement - histogram stretching and equalization - brightness optimization (brightness enhancement), - spatial enhancement - sharpening - averagening - pointing out line elements and edges (edge enhancement) - spectral enhancement - principal components analysis Image conveying By various image transformations (conveying), we get a 'new' image from a raw one, which results in emphasizing certain phenomena and attributes. Image transformation is an important step in digital processing, but for the geodesy purposes, i.e. mapping, this phase is not of essential importance. Geometric image correction Previous image processing of remote sensing is based on the analysis of radiometric and geometric characteristics. By understanding these image attributes, it is possible to correct image deformations, prove the quality and readability. Within this experiment, geometric deformations and a way of eliminating them were processed. Digital image analysis and interpretation A very important phase of satellite images processing is image analysis and interpretation. The analysis and interpretation can be visual and instrumental (by computer). The image resolution and possibility of recognizing image content are important for both of them. The analysis is a procedure of determining differences in characteristics and extraction of objects or terrain area based on their individual attributes. Visual image analysis and interpretation A visual image analysis and interpretation include registration and recognition of various useful data by eyesight. Computer added analysis and photo-interpretation-data conversion, geometric and radiometric image correction.-were done on a digital image. Elements of visual image analysis and interpretation A visual or logical analysis was done by observing images, notifying the differences and extracting military objects, which, due to their characteristics, differ very much from the surroundings. The recognition of objects was essential during data interpretation and application while processing the image. Finding differences between the object and the background was accomplished by a comparison based on the following visual elements: tone, shape, size, style, texture, shadow and associations. Digital image analysis Digital images can be stored in computer memory as data files, on the one of media (disc or magnetic tape), and can also be shown as black-white or colour images on a monitor, or as a data output as a film or a hard copy. A digital (formal) analysis is taken instrumentally. In that case images in a digital form are most often used, so the total procedure is known as digital analysis. The digital analysis contains numerous procedures, including forming and removing deformations and digital image enhancement, in order to enhance its interpretation. Information A datum is a real-time representation of an object, phenomenon or process, while only a processed datum, ready to be used, is called information. The final result and aim of the image analysis and interpretation or of the whole remote sensing process is useful information about an object on the terrain. The information gained by remote sensing of the terrain qualitatively and quantitatively differs from other types of research results.

【 授权许可】

Unknown