GeoKeyDirectoryTag
GeoKeyDirectoryTag is a metadata tag used by the GeoTIFF format to store a compact directory of geospatial keys. It serves as a central reference that describes the geographic coordinate system, map projection, and related transformation parameters used by the image data. The tag is widely supported by GIS and remote sensing software for interpreting the spatial content of GeoTIFF files. The tag is assigned the TIFF tag number 34735.
The content of GeoKeyDirectoryTag is organized as a sequence of 4-byte integers. The first four values form
Commonly used geokeys include those describing the geographic type (geographic or projected coordinate system), the specific
In practice, software reads GeoKeyDirectoryTag to determine how to interpret the image’s geospatial context, then consults