Convert TIFF to KML

Understanding TIFF and KML file formats

TIFF (Tagged Image File Format) is a widely used raster image format, especially in the fields of photography, scanning, and geospatial imaging. It supports high-quality images and can store metadata, including georeferencing information in the case of GeoTIFFs.

KML (Keyhole Markup Language) is an XML-based format used to display geographic data in mapping applications such as Google Earth. KML files can represent points, lines, polygons, and image overlays on maps.

Why convert TIFF to KML?

Converting a georeferenced TIFF (GeoTIFF) to KML allows you to overlay raster images onto maps in applications like Google Earth. This is useful for visualizing satellite imagery, scanned maps, or other spatial data in a geographic context.

How to convert TIFF to KML

To convert a TIFF or GeoTIFF to KML, you typically need to create a KML file that references the TIFF as a ground overlay. This process involves georeferencing the image and exporting it in a format compatible with KML.

Recommended software for TIFF to KML conversion

QGIS is a powerful, free, and open-source GIS application that can convert TIFF to KML:

1. Open your TIFF or GeoTIFF file in QGIS.
2. Ensure the image is georeferenced. If not, use the Raster → Georeferencer tool.
3. Right-click the raster layer and select Export → Save As....
4. In the dialog, choose KML as the format under Format (for vector data) or select Rendered Image and check Create KML SuperOverlay for raster overlays.
5. Set the output file location and click OK to export.

Alternatively, GDAL (Geospatial Data Abstraction Library) can be used via command line with the gdal_translate and gdal2tiles.py tools to create KML overlays from TIFF files.

Tips for successful conversion

• Ensure your TIFF is georeferenced; otherwise, the overlay will not align correctly on the map.
• Large TIFF files may need to be tiled or compressed for efficient use in mapping applications.
• Check the output in Google Earth or another KML-compatible viewer to verify correct placement.

Summary

Converting TIFF to KML enables you to visualize raster images as overlays in mapping software. QGIS is the best free tool for this conversion, offering both graphical and advanced export options.