Chapter 8. Raster Analysis II
In this chapter, we will cover the following recipes:
- Calculating NDVI
- Handling null values
- Setting extents with masks
- Sampling a raster layer
- Visualizing multispectral layers
- Modifying and reclassifying values in raster layers
- Performing supervised classification of raster layers
Introduction
Following the previous chapter, this chapter introduces some additional techniques for raster analysis. This chapter will show you how to work with images, how to modify raster values and classify them, and how raster layers can be used along with vector layers, thus extending the set of tools that were introduced in the recipes in the previous chapter.
Calculating NDVI
The Normalized Differential Vegetation Index is a very popular vegetation index that gives us useful information about the presence or absence of live green vegetation.
Getting ready
NDVI is calculated using a band with red spectral reflectance values, and another one with near-infrared reflectance values...