Introduction
The Institute of Geodesy and Cartography in Warsaw and SURFACES Laboratory of the University in Liege have developed methods for combining digital high resolution Russian space photographs with SPOT multispectral data as well as with topographical maps to produce a new generation of satellite image maps. The maps have been found ideal for urban planning and monitoring change detection in the Warsaw area, and are the first satellite image maps of the area. This new generation of space data offers several advantages when combined with traditional SPOT multispectral and panchromatic data for generating new types of satellite image maps and for digital topographic map revision up to the scale 1:25,000. Three types of the satellite maps of Warsaw were printed to the scale of 1:25,000. Two of the maps were printed as satellite image maps to the scale of 1:25,000 and a third one as a satellite image map with the topographical information superimposed on the image map.

Background
Since 1985, the Institute of Geodesy and Cartography (IGiK) in Warsaw has produced image maps to the scale of 1:50,000 using Russian high resolution photographs from the unmanned Kosmos satellites equipped with two or three semi-photogrammetric cameras. The focal length of the photographic lens was 1000 mm and the size of photographic film was 30 cm by 30 cm. Photographs were taken from the altitude of 280 km with a ground resolution of 6 meters.
      In 1993, the Institute of Geodesy and Cartography in Warsaw was equipped with the latest hardware and software for digital image processing both from aerial and satellite data. At the same time, very high ground resolution Russian spy photographs were available for civil applications. There are three types of high resolution Russian space photographs available today on the market: KFA-1000, KFA-3000 and KVR-1000.
      The KFA-1000 photographs are not vertical photographs. They were tilted +/- 19 degrees and the latest are tilted +/- 8 degrees from nadir line. These photographs have steroscopic overlap exceeding 60 percent so they were used by IGiK for space trangulation.
      KFA-3000 are new space photographs taken from 270 km above Earth with the camera focal length of 300 cm, and a ground resolution of 1m.

Production of the Satellite Image Maps
The IGiK obtained the high spatial resolution (2m in terrain) black and white KVR-1000 Russian photograph in the scale 1:220,000, as well as SPOT multispectral data of Warsaw area, both taken in the summer of 1992.
      The high resolution Russian satellite photo was scanned on the Photomation P-1700 Optronics at the IGiK with the aperture 25µm. Some noise implemented by the scanning procedure, as well as by the photo itself, was filtered out in the Fourier domain on the International Imaging Systems' System 600 and then smoothed on the Intergraph ImageStation Imager using a SIGMA filter. This digital image was rectified to military topomaps in the scale of 1:25,000 using well identified and distributed control points with accuracy less then 0.5 pixel. Bilinear resampling methods were used to obtain a new digitally rectified image.
      A first order polynomial transform of merged bands SPOT XS1, XS2, and XS3 was used to increase the pixel resolution from 20 by 20m to 5.8 by 5.8m. These bands were registered to the previously rectified KVR-1000 image. Note that the SPOT multispectral data were digitally enlarged more then 3.5 times.
      Different contrast enhancement was applied to the individual color channels to improve the color appearance. Finally, a few false color composites were prepared: XS3 band was coded with a red filter, KVR-1000 with green and XS1 + XS2 with blue. The map border annotation and scale bar were generated automatically using X and Y coordinates associated with the images using ERDAS Imagine's Map Composer software. Then final files were converted from RGB to CMYK using color separation software, and satellite image maps were printed on a STORK Ink-Jet printer by Geosystems in Germany.
      Production of this kind of satellite image map required efficient handling of large images, very good radiometric correction and accurate registration of all different data sets to the common cartographic projection.
      The satellite image map of Warsaw was checked against topomaps in the scale of 1:25,000 on 80 well identified points. Final planimetric RMSE x,y= +/- 7.8 m was achieved, which corresponds to 0.3 mm in the scale 1:25,000 of the final map. If higher accuracy were required, then photo points taken from aerotriangulation could be used, or coordinates could be measured directly in the field using GPS techniques.
      Another satellite image map in the scale 1:25,000 was produced where some of the features were enhanced in the Fourier domain. After digital processing on the Intergraph ImageStation Imager at the IGiK, the map was printed on a Rolland offset device by EUROSENSE in Belgium in 1994.
      This map is the first satellite image map in the scale 1:25,000 produced digitally in Poland, and is now available on the Polish market.
      The third satellite topoimage map was also produced digitally, in cooperation with the SURFACES Laboratory, to the scale of 1:25,000. The black topographic features were scanned from a few topographic map sheets in a scale of 1:50,000 on the ANATech 3640 large format scanner with 800 dpi resolution in order to create raster map files. After merging a few digitized map sheets of the Warsaw area, a new digital map was resampled to the KVR-1000 image pixel size. Boolean algebra was used for integration of the satellite image map with the digital topomap data. The result was a new satellite image map in the scale of 1:25,000 printed with the topographic information as white overlay on a BARCO Ink-Jet printer.

Conclusions
The KVR-1000 high resolution space photographs, merged with SPOT multispectral data have been successfully used for generating satellite image maps and satellite topoimage maps as well as for map updating up to the scale of 1:25,000, with accuracy accepted by the cartographic authority. These image maps were also very beneficial to the Warsaw area in its urban planning and monitoring change detection activities.

ACKNOWLEDGEMENTS
Special thanks to the Belgian and Polish Science Policy Offices for their support of a portion of this project, as well as to the specialists from the SURFACES Laboratory in University in Liege.

About the Author:
Romuald Kaczynski is an associate professor at the Institute of Geodesy and Cartography in Warsaw specializing in photogrammetry and digital image processing for mapping applications. He has worked as remote sensing specialist in Vietnam, Cuba, Ethiopia, Algeria and India. He can be contacted at: OPOLiS, Institute of Geodesy and Cartography Jasna 2/4 00-950 Warsaw, POLAND Tel/Fax: (4822)270-328.

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