Reproject Operator Description

Overview

Name:	`Reproject`
Full name:	`org.esa.snap.core.gpf.common.reproject.ReprojectionOp`
Purpose:	Reprojection of a source product to a target Coordinate Reference System.
Version:	1.0

Description

The reprojection operator is used to geo-reference data products. Beside plain reprojection it is able to use a Digital Elevation Model (DEM) to orthorectify a data product and to collocate one product with another.

The following XML sample shows how to integrate the {@code Reproject} operator in a processing graph (an Lambert_Azimuthal_Equal_Area projection using the WGS-84 datum):

    <node id="reprojectNode">
        <operator>Reproject</operator>
        <sources>
            <sourceProducts>readNode</sourceProducts>
        </sources>
        <parameters>
            <wktFile/>
            <crs>
              PROJCS["Lambert_Azimuthal_Equal_Area / World Geodetic System 1984",
                GEOGCS["World Geodetic System 1984",
                   DATUM["World Geodetic System 1984",
                      SPHEROID["WGS 84", 6378137.0, 298.257223563, AUTHORITY["EPSG","7030"]],
                   AUTHORITY["EPSG","6326"]],
                   PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]],
                   UNIT["degree", 0.017453292519943295],
                   AXIS["Geodetic longitude", EAST],
                   AXIS["Geodetic latitude", NORTH]],
                PROJECTION["Lambert_Azimuthal_Equal_Area"],
                PARAMETER["latitude_of_center", 0.0],
                PARAMETER["longitude_of_center", 0.0],
                PARAMETER["false_easting", 0.0],
                PARAMETER["false_northing", 0.0],
                UNIT["m", 1.0],
                AXIS["Easting", EAST],
                AXIS["Northing", NORTH]]
            </crs>
            <resampling>Nearest</resampling>
            <referencePixelX>0.5</referencePixelX>
            <referencePixelY>0.5</referencePixelY>
            <easting>9.5</easting>
            <northing>56.84</northing>
            <orientation>0.0</orientation>
            <pixelSizeX>0.012</pixelSizeX>
            <pixelSizeY>0.012</pixelSizeY>
            <width>135010246</width>
            <height>116629771</height>
            <orthorectify>false</orthorectify>
            <elevationModelName/>
            <noDataValue>NaN</noDataValue>
            <includeTiePointGrids>true</includeTiePointGrids>
            <addDeltaBands>false</addDeltaBands>
            <applyValidPixelExpression>false</applyValidPixelExpression>
            <retainValidPixelExpression>false</retainValidPixelExpression>
            <maskExpression>false</maskExpression>
        </parameters>
    </node>

Sources

Name	Description
`sourceProduct`	The product which will be reprojected.
`collocationProduct`	The source product will be collocated with this product.

Parameters

Name	Data Type	Default	Description	Constraints
`wktFile`	`File`		A file which contains the target Coordinate Reference System in WKT format.
`crs`	`String`		A text specifying the target Coordinate Reference System, either in WKT or as an authority code. For appropriate EPSG authority codes see (www.epsg-registry.org). AUTO authority can be used with code 42001 (UTM), and 42002 (Transverse Mercator) where the scene center is used as reference. Examples: EPSG:4326, AUTO:42001
`resampling`	`String`	`Nearest`	The method used for resampling of floating-point raster data.	value set: [Nearest, Bilinear, Bicubic]
`referencePixelX`	`Double`		The X-position of the reference pixel.
`referencePixelY`	`Double`		The Y-position of the reference pixel.
`easting`	`Double`		The easting of the reference pixel.
`northing`	`Double`		The northing of the reference pixel.
`orientation`	`Double`	`0`	The orientation of the output product (in degree).	interval: [-360,360]
`pixelSizeX`	`Double`		The pixel size in X direction given in CRS units.
`pixelSizeY`	`Double`		The pixel size in Y direction given in CRS units.
`width`	`Integer`		The width of the target product.
`height`	`Integer`		The height of the target product.
`tileSizeX`	`Integer`		The tile size in X direction.
`tileSizeY`	`Integer`		The tile size in Y direction.
`orthorectify`	`boolean`	`false`	Whether the source product should be orthorectified. (Not applicable to all products)
`elevationModelName`	`String`		The name of the elevation model for the orthorectification. If not given tie-point data is used.
`noDataValue`	`Double`		The value used to indicate no-data.
`includeTiePointGrids`	`boolean`	`true`	Whether tie-point grids should be included in the output product.
`addDeltaBands`	`boolean`	`false`	Whether to add delta longitude and latitude bands.
`applyValidPixelExpression`	`boolean`	`true`	Constrain which pixels get used based on the valid expression of the source file bands.
`retainValidPixelExpression`	`boolean`	`true`	The valid pixel expression of each of the source file bands will be retained and stored in the corresponding bands of the reprojected file.
`maskExpression`	`boolean`	`false`	Custom logical expression to constrain which pixels of the source band get used.