Book Image

QGIS Python Programming Cookbook

Book Image

QGIS Python Programming Cookbook

Overview of this book

Table of Contents (16 chapters)
QGIS Python Programming Cookbook
About the Author
About the Reviewers

Counting raster bands

A raster might have one or more bands. Bands represent layers of information within a raster. Each band has the same number of columns and rows.

Getting ready

We will again use the SatImage raster available at

Place this raster in your /qgis_data/rasters directory.

How to do it...

We will load the layer and then print the band count to the console. To do this, we need to perform the following steps:

  1. Start QGIS.

  2. From the Plugins menu, select Python Console.

  3. In the Python Console, load the layer and ensure that it is valid:

    rasterLyr = QgsRasterLayer("/qgis_data/rasters/satimage.tif", "Sat Image")
  4. Now, get the band count, which should be 3 in this case:


How it works...

It is important to note that raster bands are not zero-based indexes. When you want to access the first band, you reference it as 1 instead of 0. Most sequences within a programming context start with 0.