Built-up and vegetation extraction and density mapping using WorldView-II

Abstract

This study demonstrates the use of high resolution WorldView-II satellite data in extraction of built-up land and vegetation using normalized index techniques. The PCA 1 and NIR 2 bands-based built-up index was proposed for extracting built-up land, which exhibit high accuracy. The normalized difference vegetation index based on Red Edge and NIR 2 bands of WorldView-II produced high accuracy inthe estimation of vegetation compared to the use of Red and NIR bands. The grid technique used in estimating built-up and vegetation density from precisely classified images provided better and accurate assessment of built-up and vegetation density in heterogeneous landscape of urban areas. This shows areas of very high to high built-up density are located in the central, western and southern parts, which are primarily devoid of vegetation. This study indicates possibilities of utilizing high resolution satellite data in urban landscape characterization using a grid-based technique.

Keywords:

• built-up extraction
• normalized difference vegetation index
• density mapping
• WorldView-II

Acknowledgements

The authors would like to thank anonymous referees for the very useful comments and detailed corrections, which helped in the vast improvement in the quality of the manuscript. The authors also thank Mr. Ian Gilbert, DigitalGlobe Inc. and DigitalGlobe 8 Band Challenge Committee for providing the WorldView-II satellite data for the present research study.