Summary
Transforms a raster from one projection to another.
Usage
The coordinate system defines how your raster data is projected.
This tool guarantees that the error is less than half a pixel.
To apply the transformation without creating a new file, use the Warp tool.
You can choose a preexisting spatial reference, import it from another dataset, or create a new one.
You may want to change the coordinate system so your data is all in the same projection.
This tool can only output a square cell size.
You can save your output to BIL, BIP, BMP, BSQ, DAT, Esri Grid , GIF, IMG, JPEG, JPEG 2000, PNG, TIFF, MRF, CRF or any geodatabase raster dataset.
When storing your raster dataset to a JPEG file, a JPEG 2000 file, or a geodatabase, you can specify a Compression Type and Compression Quality in the Environments.
Projects a raster dataset into a new spatial reference using a bilinear interpolation approximation method, which projects pixels on a coarse mesh grid and uses bilinear interpolation between the pixels.
The NEAREST option, which performs a nearest neighbor assignment, is the fastest of the four interpolation methods. It is primarily used for categorical data, such as a land-use classification, because it will not change the cell values. It should not be used for continuous data, such as elevation surfaces.
The BILINEAR option uses bilinear interpolation to determine the new value of a cell based on a weighted distance average of the four nearest surrounding cells.The CUBIC option uses cubic convolution to determine the new cell value by fitting a smooth curve through the surrounding points. These are the most appropriate choices for continuous data but may cause some smoothing. Note that cubic convolution may result in the output raster containing values outside the range of the input raster. Neither of these techniques be used with categorical data because different cell values may be introduced, which may be undesirable.
The cells of the raster dataset will be square and of equal area in map coordinate space, although the shape and area a cell represents on the surface of the earth will never be constant across a raster. This is because no map projection can preserve both shape and area simultaneously. The area represented by the cells will vary across the raster. Therefore, the cell size and the number of rows and columns in the output raster may change.
Always specify an output cell size, unless you are projecting between spherical (latitude–longitude) coordinates and a planar coordinate system where you don't know what an appropriate cell size would be.
The default cell size of the output raster is determined from the projected cell size at the center of the output raster. This is also (usually) the intersection of the central meridian and latitude of true scale and is the area of least distortion. The boundary of the input raster is projected, and the minimum and maximum extents dictate the size of the output raster. Each cell is projected back to the input coordinate system to determine the cell's value.
The geographic transformation is an optional parameter when the input and output coordinate systems have the same datum. If the input and output datum are different, a geographic transformation needs to be specified.
The registration point allows you to specify the origin point for anchoring the output cells. All output cells will be an interval of the cell size away from this point. This point does not have to be a corner coordinate or fall within the raster dataset. If a Snap Raster is set in the Environment Settings, the registration point will be ignored.
CLARKE 1866 is the default spheroid if it is not inherent to the projection (such as NEWZEALAND_GRID) or another is specified with the SPHEROID subcommand.
The snap raster setting will take priority over the registration point, if both are set.
To perform a vertical transformation, check the optional Vertical parameter on the dialog box. By default, the Vertical parameter is unavailable and is only available when the input and output coordinate systems have a vertical coordinate system (VCS), and the input feature class coordinates have z-values. Also, additional data (coordinate systems data) setup needs to be installed on the system.
When you select the output coordinate system, you can choose both the geographic or projected coordinate system and a VCS. If the input and output VCS are different, an appropriate vertical and an optional geographic (datum) transformations is available. If a transformation should be applied in the opposite direction to its definition, choose the entry with the tilde (~) in front of the name.
Syntax
ProjectRaster_management (in_raster, out_raster, out_coor_system, {resampling_type}, {cell_size}, {geographic_transform}, {Registration_Point}, {in_coor_system}, {vertical})| Parameter | Explanation | Data Type |
in_raster | The raster dataset that will be transformed into a new projection. | Mosaic Layer; Raster Layer |
out_raster | The raster dataset with the new projection that will be created. When storing the raster dataset in a file format, you need to specify the file extension:
When storing a raster dataset in a geodatabase, no file extension should be added to the name of the raster dataset. When storing your raster dataset to a JPEG file, a JPEG 2000 file, a TIFF file, or a geodatabase, you can specify a Compression Type and Compression Quality in the geoprocessing Environments. | Raster Dataset |
out_coor_system | The coordinate system for the new raster dataset. Valid values for this parameter are the following:
| Coordinate System |
resampling_type (Optional) | The resampling algorithm to be used. The default is NEAREST.
The NEAREST and MAJORITY options are used for categorical data, such as a land-use classification. The NEAREST option is the default since it is the quickest and also because it will not change the cell values. Do not use either of these for continuous data, such as elevation surfaces. The BILINEAR option and the CUBIC option are most appropriate for continuous data. It is recommended that neither of these be used with categorical data because the cell values may be altered. | String |
cell_size (Optional) | Determines the cell size of the new raster using an existing raster dataset or specify its width (x) and height (y). | Cell Size XY |
geographic_transform [geographic_transform,...] (Optional) | Specifies the geographic transformation when projecting from one geographic system or datum to another. A transformation is required when the input and output coordinate systems have different datums. For information on each supported geographic (datum) transformation, see geographic_transformations.pdf located in <install location>\ArcGIS\Desktop\10.<version>\Documentation. | String |
Registration_Point (Optional) | Specifies the lower-left point for anchoring the output cells. This point does not have to be a corner coordinate or even fall within the raster dataset. The Snap Raster environment setting will take priority over the Registration Point parameter. If you want to set the registration point, make sure that Snap Raster is not set. | Point |
in_coor_system (Optional) | The coordinate system of the input raster dataset. | Coordinate System |
vertical (Optional) | Performs a vertical transformation. The parameter is only applied when the input and output coordinate systems have a vertical coordinate system, and the input feature class coordinates have z-values. When the VERTICAL keyword is used, the geographic_transform parameter can include ellipsoidal transformations and transformations between vertical datums. For example, “~NAD_1983_To_NAVD88_CONUS_GEOID12B_Height + NAD_1983_To_WGS_1984_1” transforms geometry vertices that are defined on NAD 1983 datum with NAVD 1988 heights into vertices on the WGS 1984 ellipsoid (with z-values representing ellipsoidal heights). The tilde (~) indicates reversed direction of transformation.
Many vertical transformations require additional data files that must be installed using the ArcGIS Coordinate Systems Data installation package. | Boolean |
Code sample
ProjectRaster example 1 (Python window)
This is a Python sample for the ProjectRaster tool.
import arcpy
from arcpy import env
arcpy.ProjectRaster_management("c:/data/image.tif", "c:/output/reproject.tif",\
"World_Mercator.prj", "BILINEAR", "5",\
"NAD_1983_To_WGS_1984_5", "#", "#")
ProjectRaster example 2 (stand-alone script)
This is a Python script sample for the ProjectRaster tool.
##====================================
##Project Raster
##Usage: ProjectRaster_management in_raster out_raster out_coor_system {NEAREST | BILINEAR
## | CUBIC | MAJORITY} {cell_size} {geographic_transform;
## geographic_transform...} {Registration_Point} {in_coor_system}
import arcpy
arcpy.env.workspace = r"C:/Workspace"
##Reproject a TIFF image with Datumn transfer
arcpy.ProjectRaster_management("image.tif", "reproject.tif", "World_Mercator.prj",\
"BILINEAR", "5", "NAD_1983_To_WGS_1984_5", "#", "#")
##Reproject a TIFF image that does not have a spatial reference
##Set snapping point to the top left of the original image
snapping_pnt = "1942602 304176"
arcpy.ProjectRaster_management("nosr.tif", "project.tif", "World_Mercator.prj", "BILINEAR",\
"5", "NAD_1983_To_WGS_1984_6", snapping_pnt,\
"NAD_1983_StatePlane_Washington_North.prj")
Environments
Licensing information
- ArcGIS Desktop Basic: Yes
- ArcGIS Desktop Standard: Yes
- ArcGIS Desktop Advanced: Yes