Georeferencing Existing Images

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If you already have an image that you want to use as a chart, AngelPilot offers a very basic ability to georeference it, and then save the image as a Geotiff file.

Georeferencing an image

Images are georeferenced using the following steps:

• Choose New GeoTIFF... from the file menu to bring up the Georeferencing window
• Click the Load button to import an image file
• Click on a point in the image and enter the corresponding latitude and longitude
• Repeat the previous step once, choosing a point in the opposite corner of the image
• Click the Save button

Tips for georeferencing

The two points should be as far apart in latitude and longitude as possible (e.g. one point in the bottom left, and the other in the top right).

Only images that represent a Mercator projection, are large scale, and are are orientated so that north is up, can be georeferenced by AngelPilot.

Latitude and longitude of a feature on the chart can be determined using Google Earth.