Koncepcja komputerowego cieniowania map tonalnych na przykładzie mapy Karkonoskiego Parku Narodowego

• Autorzy: Rudnicki W.

Warianty tytułu

EN

Concept of computer shading of tonal maps Karkonoski National Park example

• Języki publikacji: PL

Abstrakty

PL

W artykule zaprezentowano metodę cieniowania zdjęć lotniczych lub satelitarnych w celu uzyskania efektu ortoskopowego, bez konieczności zmiany orientacji tych obrazów na południową.

EN

Author discusses in the article method of shading maps, which are prepared on the basis of aerial and satellite photographs. Results of the research works allow for minimising pseudoscopic effect observed on aerial and satellite photographs, which are taken in sunlight on northern hemisphere. The method is based on using DTM to generate artificial shadows, which have opposite direction in relation to natural shadows produced by sunlight. As a result of applying function of image merging a map of artificial shadows makes correction to the tonal range of photographs. Function, which is applied for correction, retains mid-tones, makes image brighter in lighter parts of shadow map and makes it darker in areas, which have lower density than mean tonal values. This stage enables to eliminate almost totally pseudoscopic effect. The described method does not allow for removing natural shadows, where their contrast is too high. In order to ensure proper interpretation of aerial and satellite photographs, the added shadows conform to the rules of correct perception of spatial model. On the basis of the presented method the Landscape Map of Karkonoski National Park has been prepared (compiled from aerial photographs at the scale of 1:30 000, as well as IRS IC and SPOT satellite images). The map was created in two scales: 1:50 000 and 1:75 000. The method was also successfully applied for large-scale maps.

• Wydawca: Instytut Geodezji i Kartografii
• Czasopismo: Prace Instytutu Geodezji i Kartografii
• Rocznik: 2001
• Tom: T. 48, z. 103
• Strony: 169--179
• Opis fizyczny: Bibliogr. 6 poz., il.

Twórcy

autor

Rudnicki W.

Bibliografia

• [1] Brassel K., 1974, A Model for Automatic Hill-Shading. The American Cartographer.
• [2] Yoeli P., 1965/1966, Analytical Hill Shading. Surveying and Mapping, 25, 26.
• [3] Pawlak W., 1979, Teoretyczne podstawy cieniowania i ich zastosowanie przy opracowaniu rzeźby terenu na mapach. Polski Przegląd Kartograficzny, Warszawa.
• [4] Imhof E. 1982, Cartographic Relief Presentation.
• [5] Lucas K., Weibel R., 1995, Assessment and improvement of methods for analitycal hillshading.Preecedings of 17th International Cartographic Conference, Barcelona.
• [6] Hurni L., Sieber R., 1998, Multimedialer Atlas der Schweiz. Vermesung Photogrammetrie Kulturtechnik. Recenzował: prof. dr hab. inż. Andrzej Makowski