Labeling geospatial/tiled imagery

Aerial images are usually high-resolution images with large coverage. Their sizes can reach hundreds of megabytes (or more). Tiling is often necessary to navigate all the areas of the image and zoom in on specific areas to annotate objects.

For annotating geospatial/satellite imagery, Kili currently supports GeoTIFF files (.tif files with geospatial metadata). The standard tiff format (.tif/.tiff) is not natively supported by Kili.
When uploaded to Kili, all images larger than 30MB are automatically tiled, for better performance. This means that, technically, labeling GeoTIFF images is not different from labeling standard images and you can use all the standard tools that you’d normally use with Image-type projects. The only differences are:

When GeoTIFF files are detected, Kili switches off the asset rotation feature, to preserve the original geo-coordinates.
When exported, GeoTIFF labels are saved together with their corresponding geographic coordinates sourced from the image geospatial metadata.

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In exported annotations, x stands for longitude and y for latitude.

For details on what TIFF types are supported by Kili, refer to our list of supported TIFF raster drivers.

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To access the geographic coordinates of a specific point, hover over it and then click Alt/Option + C. The coordinates are copied to clipboard.