NDBI

Normalized Difference Built-Up Index (NDBI) is one of the commonly used remote sensing indices for the classification and analysis of built-up or urban areas using satellite images. This index uses information contained in the Near-Infrared (NIR) and Shortwave Infrared (SWIR) bands to differentiate built-up features like buildings and roads from other land covers. Some of the common applications of the NDBI include use in GIS and satellite imagery analysis, assessment of urban expansion, land-use and land-cover mapping, and environmental research. Through differences in reflectance in the NIR and SWIR bands, the index helps to identify areas with more amounts of built-up land cover. The index can be calculated using images taken using sensors such as Landsat and Sentinel-2, among others. Applications of NDBI include urban expansion assessment, infrastructure development, mapping of impervious surfaces, and change detection, among others. Use of NDBI together with other indices such as NDVI and NDWI gives a clearer view of urban environments in relation to vegetation and water.