GeoTIFF Explained
If you work with terrain rasters, you work with GeoTIFF. It is the everyday format for DEMs and orthophotos. This guide explains what makes a GeoTIFF different from an ordinary image and why it became the standard.
A TIFF that knows where it is
A GeoTIFF is a standard TIFF image with extra metadata that ties every pixel to a real-world location: a coordinate reference system, an origin and a pixel size. That metadata is what turns a picture into a map.
Because the georeferencing lives inside the file, a GeoTIFF drops onto the correct spot on the earth without a separate world file.
DEMs and orthophotos
GeoTIFF carries two very common terrain products. As a single-band raster it stores a DEM, where each pixel is an elevation. As a multi-band raster it stores an orthophoto, where each pixel is a colour.
Both share the same georeferencing, which is why a DEM and an orthophoto of the same site line up perfectly when you overlay them.
Why it is the standard
GeoTIFF is open, widely supported and self-describing, so it moves cleanly between survey, GIS and CAD tools. It also supports tiling and overviews, which let software read only the part of a huge file it needs.
That last point matters in practice: a site GeoTIFF can be gigabytes, and software that streams it stays responsive instead of loading the whole thing.
Open large GeoTIFF DEMs and orthophotos in STREAM
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