How to Georeference in QGIS?

     One of the fundamental and preliminary work that every GIS enthusiast should learn first is georeferencing. It is one of the elementary steps in most GIS. It is the process of taking an airphoto, or a scanned topographic map, and adding geographic information to the image so that GIS software can 'place' the image in its appropriate real world location. This process is completed by selecting pixels in the digital image and assigning them geographic coordinates. Usually, these coordinates are obtained by doing proper field surveys and collecting coordinates with a GPS device for few easily identifiable features in the image or the map. More frequently, an image is georeferenced to an existing image that already has embedded geographic information. Georeferencing raster data allows it to be viewed, queried, and analyzed with other geographic data. 

Georeferencing in QGIS

    One of the great benefits of QGIS is the active community who support it by developing plugins that extend the applications functionality. Georeferencing in QGIS is done via such a plugin, named the Georeferencer GDAL plugin. This  plugin is already part of QGIS installation. A step by step detailed procedure of georeferencing is illustrated by Ujaval Gandhi in his blog. Click on the links below to go to his personal blog "QGIS Tutorials and Tips".

Georeferencing Toposheets and Scanned Maps

Georeferencing Aerial Imagery

To know more about plugins in QGIS, go to the following link.

QGIS Documentation

Click on the following link to go to QGIS Training Manual.

QGIS Training Manual

To know more about GPS data, Click on the link below.

Working with GPS Data

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