GeographicCellsReference

Reference raster cells to geographic coordinates

Description

A geographic cells raster reference object encapsulates the relationship between a geographic coordinate system and a system of intrinsic coordinates anchored to the columns and rows of a 2-D spatially referenced raster grid or image.

The raster must be sampled regularly in latitude and longitude, and its columns and rows must be aligned with meridians and parallels, respectively. For more information about coordinate systems, see Intrinsic Coordinate System.

Creation

You can use any of the following functions to create a GeographicCellsReference object to reference a regular raster of cells to geographic coordinates.

georefcells — Create a geographic raster reference object.
georasterref — Convert a world file to a geographic raster reference object.
refmatToGeoRasterReference — Convert a referencing matrix to a geographic raster reference object.
refvecToGeoRasterReference — Convert a referencing vector to a geographic raster reference object.

For example, to construct a geographic raster reference object with default property settings, use this command:

R = georefcells()

R = 

  GeographicCellsReference with properties:

             LatitudeLimits: [0.5 2.5]
            LongitudeLimits: [0.5 2.5]
                 RasterSize: [2 2]
       RasterInterpretation: 'cells'
           ColumnsStartFrom: 'south'
              RowsStartFrom: 'west'
       CellExtentInLatitude: 1
      CellExtentInLongitude: 1
     RasterExtentInLatitude: 2
    RasterExtentInLongitude: 2
           XIntrinsicLimits: [0.5 2.5]
           YIntrinsicLimits: [0.5 2.5]
       CoordinateSystemType: 'geographic'
                  AngleUnit: 'degree'

Properties

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`LatitudeLimits` — Latitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

Latitude limits of the geographic quadrangle bounding the georeferenced raster, specified as a two-element vector of the form [southern_limit northern_limit].

Example: [-90 90]

Data Types: double

`LongitudeLimits` — Longitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

Longitude limits of the geographic quadrangle bounding the georeferenced raster, specified as a two-element vector of the form [western_limit eastern_limit].

Example: [-100 180]

Data Types: double

`RasterSize` — Number of rows and columns of the raster or image associated with the referencing object
`[2 2]` (default) | two-element vector of positive integers

Number of rows and columns of the raster or image associated with the referencing object, specified as a two-element vector, [m n], where m represents the number of rows and n the number of columns. For convenience, you can assign a size vector having more than two elements. This enables assignments like R.RasterSize = size(RGB), where RGB is m-by-n-by-3. In cases like this, the object stores only the first two elements of the size vector and ignores the higher (nonspatial) dimensions.

Example: [200 300]

Data Types: double

`RasterInterpretation` — Geometric nature of the raster
`'cells'` (default)

This property is read-only.

Geometric nature of the raster, specified as 'cells'. The value 'cells' indicates that the raster comprises a grid of quadrangular cells, and is bounded on all sides by cell edges. For an m-by-n raster, points with an intrinsic x-coordinate of 1 or n or an intrinsic y-coordinate of 1 or m fall within the raster, not on its edges.

Data Types: char

`AngleUnit` — Unit of measurement used for angle-valued properties
`'degree'` (default)

Unit of measurement used for angle-valued properties, specified as 'degree'.

Cannot be set.

Data Types: char

`ColumnsStartFrom` — Edge from which column indexing starts
`'south'` (default) | `'north'`

Edge from which column indexing starts, specified as 'south' or 'north'.

Example: 'south'

Data Types: char

`RowsStartFrom` — Edge from which row indexing starts
`'west'` (default) | `'east'`

Edge from which row indexing starts, specified as 'west' or 'east'.

Example: 'east'

Data Types: char

`CellExtentInLatitude` — Extent in latitude of individual cells
`1` (default) | positive numeric scalar

Extent in latitude of individual cells, specified as a positive numeric scalar. Distance, in units of latitude, between the northern and southern limits of a single raster cell. The value is the same for all cells in the raster.

Example: 2.5

Data Types: double

`CellExtentInLongitude` — Extent in longitude of individual cells
`1` (default) | positive numeric scalar

Extent in longitude of individual cells, specified as a positive numeric scalar. Distance, in units of longitude, between the western and eastern limits of a single raster cell. The value is always positive, and is the same for all cells in the raster.

Example: 2.5

Data Types: double

`RasterExtentInLatitude` — Latitude extent ("height") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

This property is read-only.

Latitude extent ("height") of the quadrangle covered by the raster, specified as a positive numeric scalar.

Example: 2

Data Types: double

`RasterExtentInLongitude` — Longitude extent ("width") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

This property is read-only.

Longitude extent ("width") of the quadrangle covered by the raster, specified as a positive numeric scalar.

Data Types: double

`XIntrinsicLimits` — Raster limits in intrinsic x coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

This property is read-only.

Raster limits in intrinsic x coordinates, specified as a two-element row vector of positive integers, [xMin xMax]. For an m-by-n raster, XIntrinsicLimits equals [0.5, m+0.5], because the RasterInterpretation is 'cells'.

Example: [0.5 2.5]

Data Types: double

`YIntrinsicLimits` — Raster limits in intrinsic y coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

This property is read-only.

Raster limits in intrinsic y coordinates, specified as a two-element row vector of positive integers, [yMin yMax]. For an m-by-n raster, YIntrinsicLimits equals [0.5, n+0.5], because the RasterInterpretation is 'cells'.

Data Types: double

`CoordinateSystemType` — Type of coordinate system to which the image or raster is referenced
`'geographic'` (default)

This property is read-only.

Type of coordinate system to which the image or raster is referenced, specified as 'geographic'.

Data Types: char

`GeographicCRS` — Geographic coordinate reference system
`[]` (default) | `geocrs` object

Geographic coordinate reference system (CRS), specified as a geocrs object. A geographic CRS consists of a datum (including its ellipsoid), prime meridian, and angular unit of measurement.

Object Functions

`contains`	Determine if geographic or map raster contains points
`geographicToDiscrete`	Transform geographic to discrete coordinates
`geographicToIntrinsic`	Transform geographic to intrinsic coordinates
`intrinsicToGeographic`	Transform intrinsic to geographic coordinates
`intrinsicXToLongitude`	Convert from intrinsic x to longitude coordinates
`intrinsicYToLatitude`	Convert from intrinsic y to latitude coordinates
`latitudeToIntrinsicY`	Convert from latitude to intrinsic y coordinates
`longitudeToIntrinsicX`	Convert from longitude to intrinsic x coordinates
`sizesMatch`	Determine if geographic or map raster object and image or raster are size-compatible
`worldFileMatrix`	Return world file parameters for transformation

More About

expand all

Intrinsic Coordinate System

A 2-D Cartesian system with its x-axis running parallel to the rows of a raster or image and its y-axis running parallel to the columns. x increases by 1 from column to column, and y increases by 1 from row to row.

Mapping Toolbox™ and Image Processing Toolbox™ use the convention for the location of the origin relative to the raster cells or sampling points such that, at a sample location or at the center of a cell, x has an integer value equal to the column index. Likewise, at a sample location or at the center of a cell, y has an integer value equal to the row index. For details, see Image Coordinate Systems (Image Processing Toolbox).

Documentation

GeographicCellsReference

Description

Creation

Properties

`LatitudeLimits` — Latitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

`LongitudeLimits` — Longitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

`RasterSize` — Number of rows and columns of the raster or image associated with the referencing object
`[2 2]` (default) | two-element vector of positive integers

`RasterInterpretation` — Geometric nature of the raster
`'cells'` (default)

`AngleUnit` — Unit of measurement used for angle-valued properties
`'degree'` (default)

`ColumnsStartFrom` — Edge from which column indexing starts
`'south'` (default) | `'north'`

`RowsStartFrom` — Edge from which row indexing starts
`'west'` (default) | `'east'`

`CellExtentInLatitude` — Extent in latitude of individual cells
`1` (default) | positive numeric scalar

`CellExtentInLongitude` — Extent in longitude of individual cells
`1` (default) | positive numeric scalar

`RasterExtentInLatitude` — Latitude extent ("height") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

`RasterExtentInLongitude` — Longitude extent ("width") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

`XIntrinsicLimits` — Raster limits in intrinsic x coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

`YIntrinsicLimits` — Raster limits in intrinsic y coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

`CoordinateSystemType` — Type of coordinate system to which the image or raster is referenced
`'geographic'` (default)

`GeographicCRS` — Geographic coordinate reference system
`[]` (default) | `geocrs` object

Object Functions

More About

Intrinsic Coordinate System

See Also

Functions

Objects

Mapping Toolbox Documentation

Support

Documentation

GeographicCellsReference

Description

Creation

Properties

LatitudeLimits — Latitude limits of the geographic quadrangle bounding the georeferenced raster [0.5 2.5] (default) | two-element vector

LongitudeLimits — Longitude limits of the geographic quadrangle bounding the georeferenced raster [0.5 2.5] (default) | two-element vector

RasterSize — Number of rows and columns of the raster or image associated with the referencing object [2 2] (default) | two-element vector of positive integers

RasterInterpretation — Geometric nature of the raster 'cells' (default)

AngleUnit — Unit of measurement used for angle-valued properties 'degree' (default)

ColumnsStartFrom — Edge from which column indexing starts 'south' (default) | 'north'

RowsStartFrom — Edge from which row indexing starts 'west' (default) | 'east'

CellExtentInLatitude — Extent in latitude of individual cells 1 (default) | positive numeric scalar

CellExtentInLongitude — Extent in longitude of individual cells 1 (default) | positive numeric scalar

RasterExtentInLatitude — Latitude extent ("height") of the quadrangle covered by the raster 2 (default) | positive numeric scalar

RasterExtentInLongitude — Longitude extent ("width") of the quadrangle covered by the raster 2 (default) | positive numeric scalar

XIntrinsicLimits — Raster limits in intrinsic x coordinates [0.5 2.5] (default) | two-element row vector of positive integers

YIntrinsicLimits — Raster limits in intrinsic y coordinates [0.5 2.5] (default) | two-element row vector of positive integers

CoordinateSystemType — Type of coordinate system to which the image or raster is referenced 'geographic' (default)

GeographicCRS — Geographic coordinate reference system [] (default) | geocrs object

Object Functions

More About

Intrinsic Coordinate System

See Also

Functions

Objects

Mapping Toolbox Documentation

Support

`LatitudeLimits` — Latitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

`LongitudeLimits` — Longitude limits of the geographic quadrangle bounding the georeferenced raster
`[0.5 2.5]` (default) | two-element vector

`RasterSize` — Number of rows and columns of the raster or image associated with the referencing object
`[2 2]` (default) | two-element vector of positive integers

`RasterInterpretation` — Geometric nature of the raster
`'cells'` (default)

`AngleUnit` — Unit of measurement used for angle-valued properties
`'degree'` (default)

`ColumnsStartFrom` — Edge from which column indexing starts
`'south'` (default) | `'north'`

`RowsStartFrom` — Edge from which row indexing starts
`'west'` (default) | `'east'`

`CellExtentInLatitude` — Extent in latitude of individual cells
`1` (default) | positive numeric scalar

`CellExtentInLongitude` — Extent in longitude of individual cells
`1` (default) | positive numeric scalar

`RasterExtentInLatitude` — Latitude extent ("height") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

`RasterExtentInLongitude` — Longitude extent ("width") of the quadrangle covered by the raster
`2` (default) | positive numeric scalar

`XIntrinsicLimits` — Raster limits in intrinsic x coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

`YIntrinsicLimits` — Raster limits in intrinsic y coordinates
`[0.5 2.5]` (default) | two-element row vector of positive integers

`CoordinateSystemType` — Type of coordinate system to which the image or raster is referenced
`'geographic'` (default)

`GeographicCRS` — Geographic coordinate reference system
`[]` (default) | `geocrs` object