EXTRACTION OF URBAN IMPERVIOUS SURFACE FROM MULTI-TEMPORAL WORLDVIEW-2 IMAGERY USING SPECTRAL MIXTURE ANALYSIS: A COMPARATIVE STUDY

Impervious surface is considered as a key indicator of urban environment quality and urbanization. Many studies have attempted to extract urban impervious surface using multispectral images of medium and high resolution, especially images acquired in summer, as they achieved higher accuracy. However, the use of summer images may underestimate impervious surface area, since some impervious surfaces are obscured by deciduous tree crowns in summer. This paper compared the results of impervious surface extracted using two-temporal Worldview-2 multispectral images acquired in summer and winter by linear spectral mixture analysis and analyzed the differences between the results. The results indicated that impervious surface extraction from winter image produced a similar accuracy with summer image. However, the area of impervious surface extracted from winter image was much higher than that from summer image by nearly 20% in study area.