Australian Geographic Reference Image
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Australian Geographic Reference Image 
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**Authored on**: 2018-03   
**Updated on**: 2020-08  
**License**: CC BY Attribution 4.0 International License

View the [original metadata page](https://cmi.ga.gov.au/data-products/dea/116/australian-geographic-reference-image) for the most up-to-date information on this product.

Abstract
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It is important to ensure that satellite images are consistently and accurately registered to allow the maximum extraction of information.

What this product offers
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The Australian Geographic Reference Image (AGRI) is a consistent and accurate reference image for rectification of imagery from multiple sources at resolutions of 2.5 m or less.

The AGRI provides a consistent base image intended, at the time of production, to provide an important foundation for future mapping and monitoring across Australia.

Applications
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The AGRI is a resource for both users and providers of satellite imagery covering Australia in:

- Government agencies – Commonwealth, State and Local
- Research institutions
- Spatial Information Industry
- International satellite operators

Ground Control Points from the AGRI have fed into satellite image processing systems of the United States Geological Survey and of the European Space Agency. Consequently, imagery from the Landsat satellites and from the Copernicus Sentinel satellites are accurately and consistently geo-registered across Australia.

Similarly, commercial satellite operators are understood to have used the AGRI to improve their product quality.

Reference image – image to image rectification, image chip source, quality control layer  
Basemap – feature revision and verification, reference layer

Accuracy and limitations
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Absolute geometric accuracy: 5.6m CEP90.

Cloudy over some areas.

Publications
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Ravanbakhsh, M., Wang, L.-W., Fraser, C. S., & Lewis, A. (2012). Generation of the Australian Geographic Reference Image Through Long-Strip Alos Prism Orientation. ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 39B1, 225–229. 

References
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Ravanbakhsh, M., Wang, L.-W., Fraser, C. S., & Lewis, A. (2012). Generation of the Australian Geographic Reference Image through long-strip ALOS PRISM orientation. *ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences*, *XXXIX-B1*, 225–229. 

Rottensteiner, F., Weser, T., Lewis, A., & Fraser, C. S. (2009). A strip adjustment approach for precise georeferencing of ALOS optical imagery. *IEEE Transactions on Geoscience and Remote Sensing*, *47*(12), 4083–4091. 

Contacts
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For questions or more information about this product, email [DEA Support](mailto:dea@ga.gov.au?subject=Data%20Products%20support%20for%20Australian%20Geographic%20Reference%20Image).