Geodetski list, Vol. 70 (93) No. 1, 2016.
Review article
Comparison of Vegetation Index Value Based on Digital Number and Top of Atmosphere Reflectance
Luka Rumora
orcid.org/0000-0002-2362-6685
; Faculty of Geodesy, University of Zagreb, Zagreb, Croatia
Ivan Medved
; Croatian Forest Research Institute, Jastrebarsko, Croatia
Ivan Pilaš
; Croatian Forest Research Institute, Jastrebarsko, Croatia
Damir Medak
; Faculty of Geodesy, University of Zagreb, Zagreb, Croatia
Abstract
Remote sensing is common way for collecting large amount of data across large area as a result of satellite missions. Collected satellite images allows gathering informations for understanding Earth processes. Biggest advantage was free satellite data access. Accessing large amount of free data, number of methods for processing gathered satellite images were developed. With technology development, processed data have better quality. This article shows two ways of processing satellite data for gathering informations about quality of vegetation index calculated with digital number and with reflectance. Steps of calculation reflectance for each pixel from digital number is shown. Leaps in results, caused by clouds, were analysed by visual interpretation of image and from results of calculated normalized difference vegetation index (NDVI).
Keywords
digital number; top of atmosphere reflection; normalized difference vegetation index; Landsat 7
Hrčak ID:
156883
URI
Publication date:
25.3.2016.
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