GeoTIFF (.tif, .tiff)

Background & Context

    • GIS extension of the TIFF format.
    • Used for archiving and exchanging aerial photography or terrain data.
    • Binary format.
    • Contains rasters or digital elevation models (DEM).
    • Digital elevation models are stored as a raster of elevation values.

Import

  • Import["file","GeoTIFF"] imports a GeoTIFF file and returns it as an image.
  • Import["file",{"GeoTIFF","elem"]} imports the specified element from a GeoTIFF file.
  • Import["file.tif",{{elem1,elem2,…}}] imports multiple elements.
  • The import format can be specified with Import["file","GeoTIFF"] or Import["file",{"GeoTIFF",elem,…}].
  • See the following reference pages for full general information:
  • Importimport from a file
    CloudImportimport from a cloud object
    ImportStringimport from a string
    ImportByteArrayimport from a byte array

Import Elements

  • General Import elements:
  • "Elements" list of elements and options available in this file
    "Summary"summary of the file
    "Rules"list of rules for all available elements
  • Data representation elements:
  • "Data"array of color or elevation values
    "Graphics"image represented as a Graphics object
    "Image"image object
  • Advanced Import elements:
  • "BitDepth"number of bits used to encode a color channel in the file
    "Channels"the number of color channels used in the file
    "Summary"summary of the file
  • Import by default uses the "Image" element for the GeoTIFF format.
  • Metadata elements:
  • "ColorSpace"color encoding used in the file
    "DataFormat"type used to represent elevation or color values
    "ElevationRange"range of elevation data in meters
    "RasterSize"size of the terrain grid
    "SpatialRange"range of geographic coordinates, given in coordinate system units
    "SpatialAffineTransform"relation between pixel space and projected coordinates
  • Import["file.dem","ElevationRange"] gives the range {zmin,zmax} of elevation values in units of meters.
  • Import["file.dem","SpatialRange"] gives the bounding coordinates of the geographic region covered by the file as an expression of the form {{latmin,latmax},{longmin,longmax}}.
  • Elements representing the geodetic datum and reference ellipsoid used in the file:
  • "CoordinateSystem"name of the coordinate system used in the file
    "Datum"geodetic datum
    "SemimajorAxis"semimajor axis of the reference ellipsoid in meters
    "SemiminorAxis"semiminor axis of the reference ellipsoid in meters
    "InverseFlattening"inverse flattening of the ellipsoid
    "LinearUnits"coordinate system units
  • Elements specifying the cartographic projection and its parameters:
  • "Projection"projection name and parameters
    "Centering"latitude and longitude defining the origin of the projection
    "StandardParallels"standard parallels
    "CentralScaleFactor"scale factor at the central meridian or center of projection
    "GridOrigin"grid coordinates {n,e} of the central parallel and meridian
    "ProjectionName"Wolfram Language standard name of the projection used
    "ReferenceModel"what reference sphere or ellipsoid to use
  • Accessing low-level meta-information from the file:
  • "CoordinateSystemInformation"raw parameters of the coordinate system as stored in the file
  • See the reference page for GeoProjectionData for full information on cartographic projections.

Options

Examples

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Basic Examples  (2)

Import a GeoTIFF file:

Summary of an image:

Scope  (2)

Combine two different elements:

Import image metainformation:

Import Elements  (30)

Available Elements  (2)

List of available elements:

Import all elements as a list of rules:

Data Representation  (7)

"Data"  (1)

Import the image data:

Construct an image of appropriate type:

"Graphics"  (1)

Import as Graphics object:

"Image"  (2)

Import as an Image object:

The default element is also "Image":

Import only the specified rows:

Import specified rows and columns:

"BitDepth"  (1)

Get the bit count for the representation of each color channel:

"Channels"  (2)

Get the number of image channels used:

Get the image summary:

Metadata  (7)

"ColorSpace"  (1)

Get the color encoding used in the file:

"DataFormat"  (1)

Get the type used to represent elevation or color values:

"ElevationRange"  (1)

Minimal and maximal elevation in meters of raster data, assuming it represents a digital elevation model:

"MetaInformation"  (1)

Get all the metadata:

"RasterSize"  (1)

Get the pixel dimensions of the raster:

"SpatialRange"  (1)

Get the range of geographic coordinates given in coordinate system units:

"SpatialAffineTransform"  (1)

Get an affine transformation transforming coordinates in the pixel space to coordinates in the cartographic reference system:

The origin of coordinates lies in the upper-left corner of the raster image, as can be explicitly checked:

Datum and Reference Ellipsoid  (6)

"CoordinateSystem"  (1)

Name of the cartographic coordinate system including the datum:

"Datum"  (1)

Name of the datum:

"SemimajorAxis"  (1)

Get the semimajor axis of the reference ellipsoid in meters:

"SemiminorAxis"  (1)

Get the semiminor axis of the reference ellipsoid in meters:

"InverseFlattening"  (1)

Get the inverse flattening of the ellipsoid:

"LinearUnits"  (1)

Units of the cartographic coordinates:

Cartographic Projection  (8)

"Projection"  (1)

Name and parameters of the cartographic projection (if any):

"Centering"  (1)

Centering of the cartographic projection:

"StandardParallels"  (1)

Standard parallels of the cartographic projection, if any:

"CentralScaleFactor"  (1)

Central scale factor of the cartographic projection:

"GridOrigin"  (1)

Grid origin of the cartographic projection:

"ProjectionName"  (1)

Name of the cartographic projection:

"ReferenceModel"  (1)

Reference model of the cartographic projection:

"CoordinateSystemInformation"  (1)

Information about the cartographic reference system using the WKT specification:

Import Options  (4)

ImageSize  (1)

Specify the image size of the displayed image:

"RasterBands"  (1)

In this case the raster only has a single channel:

Import the first raster band:

RasterSize  (1)

By default, the image is imported in its full resolution:

Specify the raster size of the imported raster image: