THE REVISION OF IRANIAN 1:25000 SCALE TOPOGRAPHIC MAPS BY KVR-1000 IMAGE USING RATIONAL FUNCTION MODEL G. Jamebozorg , M. J. Valadan Zoej , S. Sadeghian a b a a National Cartographic Center, Tehran, Iran, P.O.Box: 13185-1684 – (Jame-b, Sadeghian)@ncc.neda.net.ir b Faculty of Geodesy and Geomatics Engineering, K.N.Toosi University of Technology, No. 1346, P.O.Box: 19697, Tehran, Iran - Valadanzouj@kntu.ac.ir KEY WORDS: Revision, KVR-1000 Image, Rational Function model, Polynomial, Information Content, 1:25000 Topographic Maps ABSTRACT: Nowadays, due to improvements in satellite technology, remote sensing data is applied for mapping at different scales. In Iran, there is a necessity to utilize satellite imagery as a complementary data source to aerial photographs. One of the main reasons for this, aside from the usual advantages of this technology, is the ability to map and revise border areas having aerial access limitations due to security reasons. This is especially true for Iran’s 1:25000 scale base maps. In this paper the revision process of 1:25000 scale topographic maps will be discussed and explained. Generally, the satellite images can be applied either in the change detection phase or in applying the changes to the maps. In this research, KVR-1000 image, have been used in applying (revision) to a 1:25000 scale base map. Successful exploitation of the accuracy potential of KVR-1000 depends on good panoramic model for the sensor modeling. But the camera information and interior orientation parameters were not available. Therefore the rational function model has been used and its flexibility and its good accuracy is demonstrated. Based on obtained results, KVR-1000 images, while having required planimetric accuracy at scale of 1:25000 (about 7.5m), provides the required information contents for such maps. 1. INTRODUCTION When? Revision how? 1.Surveying In Iran, production of 1:25000 scale topographic maps has been started over ten years ago. At the moment about 7000 sheets are produced and more than 3000 sheets is under production. These maps are produced by photogrammetric method using aerial images taken at 1:40000 scale. One of the big problems that NCC is now facing, regarding these maps, is the changes on the features during these years. As a result nearly all these maps have to be revised and up to dated as soon as possible. Satellite images may offer the fast and cheap solution for this problem. This paper tries to show the capability of the KVR-1000 Russian satellite photograph for revision of Iranian 1:25000 scale topographic maps. 2.Terrestrial photogrammetry 3.Aerial photogrammetry 4.Space photogrammetry Where? After the introduction, Sections 2, 3 discuss the theoretical aspect of map revision including: the time of revision and the places to be revised (Figure1). In section 4, the methods of revision explained. Section 5 outlined the capability of KVR-1000 for revising of 1:25000 scale topographic maps. It also discusses different types of the mathematical models for geometric correction of KVR-1000 images and describes the potential of KVR-1000 images for providing qualitative information that is necessary for 1:25000 scale maps. The paper will concluded in section 6. 1. Image selection 2. Extraction of ground control point 3. Geometric correction 4. Test of accuracy 5. Superimposition old map on image 6. Updating of existing map 7. Information content Figure1. Revision process 2. PLANNING REVISION (WHEN?) There are three main alternative ways in which the revision of mapping can be planned. These are: a. Cyclic revision, which would aim at the revision of the whole series over a fixed period years. b. Selective revision, which would try to achieve revision of individual sheets by an order of priority that is governed by rate of change or urgency of demand and not by fixed periods. c. Continuous revision, Which relies on a continuous inflow of information, field survey and etc. to maintain sheets in an up-to-date condition. In Iran, for planning revision blocks of 1:25000 scale maps, the features of each blocks are classified to three main