chapter twelve
This chapter covers:
- Loading raster data
- Spatial aggregate raster functions
- Using geometries to clip rasters
- Accessing pixel values and isolating bands
- Retiling rasters
- Raster statistical functions
- Map algebra functions
In this chapter we’ll focus on the use of raster aggregate functions, functions to manipulate rasters down to the pixel level, and functions for deriving additional rasters and geometries. We’ll also demonstrate built-in summary statistics functions that you can use to learn more about the distribution of pixel values. You’ll see in the examples that we consistently use geometry to isolate pixel values of interest. Being able to use geometry and raster in tandem is a powerful aspect of PostGIS.