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. To perform a vertical transformation, check the optional Vertical parameter on the dialog box. The snap raster setting will take priority over the registration point if both are set. If a snap raster is set in the Environment settings, the registration point will be ignored.ĬLARKE 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. This point does not have to be a corner coordinate or fall within the raster dataset. All output cells will be an interval of the cell size away from this point. The registration point allows you to specify the origin point for anchoring the output cells. If the input and output datum are different, a geographic transformation must be specified. The geographic transformation is an optional parameter when the input and output coordinate systems have the same datum. Each cell is projected back to the input coordinate system to determine the cell's value. The boundary of the input raster is projected, and the minimum and maximum extents dictate the size of the output raster. This is typically the intersection of the central meridian and latitude of true scale and is the area of least distortion. The default cell size of the output raster is determined from the projected cell size at the center of the output raster. Therefore, the cell size and the number of rows and columns in the output raster may change.Īlways specify an output cell size, unless you are projecting between spherical (latitude–longitude) coordinates and a planar coordinate system and don't know the appropriate cell size. The area represented by the cells will vary across the raster. This is because no map projection can preserve both shape and area simultaneously. 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. Neither of these options should be used with categorical data because different pixel values may be introduced, which may be undesirable. Cubic convolution may result in the output raster containing values outside the range of the input raster. These are the most appropriate choices for continuous data but may cause some smoothing. The Cubic option uses cubic convolution to determine the new pixel value by fitting a smooth curve through the surrounding points. The Bilinear option uses bilinear interpolation to determine the new value of a pixel based on a weighted distance average of the four nearest surrounding pixels. It should not be used for continuous data, such as elevation surfaces. It is primarily used for categorical data, such as a land-use classification, because it will not change the pixel values. The Nearest option, which performs a nearest neighbor assignment, is the fastest of the four interpolation techniques. When storing a raster dataset to a JPEG format file, a JPEG 2000 format file, or a geodatabase, you can specify a Compression Type value and a Compression Quality value in the geoprocessing environments. You can save the output to BIL, BIP, BMP, BSQ, DAT, Esri Grid, GIF, IMG, JPEG, JPEG 2000, PNG, TIFF, MRF, or CRF format, or any geodatabase raster dataset. This tool can only output a square pixel size. You can choose a preexisting spatial reference, import it from another dataset, or create one. To apply the transformation without creating a file, use the Warp tool. This tool guarantees that the error range is less than half a pixel. You can use the same coordinate system for your data so it will all be in the same projection.Ī raster dataset is projected into a new spatial reference using a bilinear interpolation approximation method that projects pixels on a coarse mesh grid and uses bilinear interpolation between the pixels. The coordinate system defines how your raster data is projected.
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