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QGIS is a cross-platform, free and open-source software used all across the world. From academics to NGO, from small business to enterprise-level organisations, the growing adoption of open-data and communities makes QGIS a significant and worthy alternative to mainstream licensed software applications.

How Nearmap and QGIS Work

QGIS has native view, edit and analysis features operating with raster data. Some common Raster Operations includes:

  • Slope, aspect, hill-shade, terrain calculation
  • Data extraction
  • Elevation and profile analysis

Image RemovedQGIS is an open source GIS desktop application that you can use to easily display Nearmap's DSM (elevation) data. 

The DSM data is delivered in a GeoTIFF file.

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Info

Note: This application was not created by Nearmap. It is built, updated, and supported by QGIS. If you experience issues with this application, or would like to see improvements, please contact QGIS directly.

Tested version at time of document release: QGIS. 2.18.15.

This guide includes the following sections:

Table of Contents

Viewing Nearmap DSM Imagery

  1. Open QGIS and Add Raster Layer by clicking the second icon on the left hand menu, or by selecting Layer Add Layer → Add Raster Layer from the top menu:
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  2. Browse and select the geocoded .tif file:
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    You may need to zoom to the layer by s
    electing View Zoom to Layer.

Classifying According to Z Value

  1. Double click the DSM layer in the Layers Panel to access the Layer Properties, then select the Style option:
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    1. Under Band rendering change the Render type to Singleband pseudocolor and click Classify:
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    2. Click Apply, then OK:
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      The elevation values are displayed on the Layers Panel.

Elevation Profile

  1. Search for "profile" in the Plugins menu, and select Profile tool. If the plugin is not installed, install it. 
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  2. Select Plugins → Profile Tool → Terrain profile:
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  3. Draw a line or a path, then click Add Layer, and the elevation profile for that line/path will be displayed:
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Raster to Vector

  1. Select Processing → Toolbar:
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  2. In the Processing Toolbox select GDAL/OGR [48 geoalgorithms] → [GDAL] Conversion → Polygonize (raster to vector):
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  3. Click Run:
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  4. The result displays the vectorized version of the DSM model:
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