QUICKBIRD SATELLITE IMAGES APPLICATION TO 1: TOPOGRAPHIC CHART ACTUALIZATION

Transcription

1 QUICKBIRD SATELLITE IMAGES APPLICATION TO 1: TOPOGRAPHIC CHART ACTUALIZATION Piotr Walczykowski Michal Kedzierski Military University of Technology 2 Kaliskiego Str Warsaw, Poland pwalczykowski@wat.edu.pl mkedzierski@wat.edu.pl ABSTRACT The authors concentrate here on QuickBird satellite images application to actualizing the 1: topographic chart. The paper presents the entire process of actualizing, starting with the description of the actualized subject, data, preparatory work, processing the input data and methods and technology of actualizing topographic charts by means of QuickBird satellite images. The paper presents methods of actualization developed for Erdas Imagine software of Leica Geosystems. INTRODUCTION Topography deals with cartographic materials presenting elements of the geographic environment of the Earth s surface and their spatial relations. It is one of the basic sources of terrain information. Topographic charts of the 1: scale prepared and actualized for the whole country area are the base for the national system of geographic information about terrain (GIS). The need to update the 1: topographic chart is then obvious. Actualizing the topographic charts is a set of jobs and organizational-and-technical actions that lead to synchronizing the topographic chart content with the actual status in the terrain as well as actualizing the descriptions related with the content. It is done by introducing appropriate corrections to the topographic chart and amendments to the content according to the real changes. Frequency of updating depends on the speed of changes in terrain and the need of updating for the purposes of the national economy and defense. It is assumed that for urban and industrial areas, along the coasts, in the border areas and along water routes it should be done every 5 to 10 years, while for the remaining areas - every 15 years. The most actual geodetic, cartographic, photogrammetric materials and descriptions are used for actualizing the 1: topographic chart. ENTRANCE (INPUT) DATA Object of Actualization Object of actualization was topographic map in scale 1:

2 Figure 1. Fragment of topographic map in scale1: subjected ACTUALIZATION. Source for Actualization Data For actualization of topographic map in scale 1:10000 take imagine from satellite QuickBird about following parameter: Data format: tif Size of scene: 5536 x 6491 pixels spectral resolution: nm spatial resolution GSD: 0.60 m radiometrical resolution: 11 bits Figure 2. Fragment of satellite scene in this same range that topographic map.

3 Figure 3. Basic parameters of statistic satellite scene. Figure 4. Satellite image histogram. PREPARATION DATA FOR ACTUALIZATION Actualization has effeced in two stage. For searching out of changes has used software Erdas Imagine Leica of Geosystems Software, for creation drawing of vector has used software Iras C of Intergraph. For preparation of data for both of systems has performed conversion of satellite scene on 11 bit format Erdas Imagine (img) and on 8 bit format.tif for software Iras C. Fragment of topographic map in scale 1: has scaned (including range of fragment satellite scene). Using software Iras C has executed transformation of raster of map for coordinate system, in which map was. Next, for so convert image of map has executed transformation of satellite scene ACTUALIZATION OF TOPOGRAPHIC MAP Searching out of changes was first period of actualization. For searching out of changes has used software Erdas Imagine. It use function swipe and blend in this purpose ( shadow and penetration two image.

4 Table 1. Operation of function swipe - shadow satellite image through map image

5 Table 2. Operation of function blend - penetration satellite image by map image After searching out of changes has created vector image of changes in softwar Iras C drawing objects on base of raster image After drawing changes has convesioned file of changes format dgn on format arcinfo (read by Erdas Imagine) and has performed second iteration for searching of changes (in view of big out-of-date of topographic map).

6 Table 3. Secondary searching out of changes After searching out of changes has created vector image of changes next again. In result of these actions fragment of topographic map in scale 1:10000 has been actualization. Figure 5. Vector image of changes - result actualization of topographic map in scale 1:10000.

7 Figure 6. Topographic map after actualizatin - image of changes put on map.

8 Figure 7. Image of changes put on satellite scene. CONCLUSIONS Satellite scene of QuickBird was suitable to use for actualization of topographic map in scale 1: Delivered satellite scen was almost vertical so actualization of high building not supplied many difficulties, because image of roof of building approximatel covered with image of first floor. 11 bit radiometrical resolution image helps with interpretation of object in shadows or semi-shadow superbly or about weak or moderate densities on image. The actualization has effected in softwar Iras C on image convesioned for resolution 8 bits, what uhas made impossible to use of full specificity of satellite scene from satellite QuickBird. Actualization Modernization in checked off areas on following drawing was practically not possible.

9 Figure 8. Cloudy areas on satellite scene. 11 bit radiometrical resolution image does not eliminate this inconvenience but it limits her.using Erdas Imagine for searching out changes speeds up this process and using of function swipe and blend makes work simplest and nicest REFERENCES Butowtt J., Kaczyński R. Fotogrametria Military University of Technology, Warsaw 2003, Kaczynski R, Ewiak I. Correction of Ikonos and QuickBird data for orthophotomaps generation ACRS Vietnam, 2005