How to do Proximity analysis in QGIS?

Proximity is a neighbourhood function of GIS. It is similar to buffer analysis that we do for Vector but if it’s done for Raster then it is called proximity in GIS. 

In this article I’m going to show how it’s done in QGIS.

Since, there will be distance measurement make sure you use Projected coordinate system which has unit meters instead of Geographic coordinate system. Here I will be using WGS84 44N.

Follow the following steps:

Step 1: Loading data

Load your raster data ‘Raster_road’ in QGIS simply by dragging it to layer panel.

Step 2: Processing Toolbox

Go to Processing toolbox search for ‘Proximity’ under Raster analysis of GDAL section you will get ‘Proximity (raster distance)’ double left click it to get below interface.

Step 3: Parameters settings
Give input layer ‘Raster_road’, distance units ‘Georeferenced coordinates’, Max distance to generate ‘1500’, No data value to use as ‘Not Set’ and save it to as file ‘Proximity_road’ and run it.

Here we used Georeferenced unit as distance units so that output raster will have cell values representing no. of units in the current Coordinate Reference System(CRS), with each cell from Raster_road.

On successful run you will get following output.

Step 4: Symbology

Double left click ‘Proximity_road’ layer -> Symbology -> Make max value as ‘1500’(since we want range of buffer to 1500 only) -> click apply

Finally, you will see following output.

So, that’s all from us for today.

Happy analysis!