If necessary, you can enter one or more NoData values in the output mosaic. For example, to specify that channel 1 has a NoData value of -9999, channel 2 is 0, and channel 3 is 255, enter -9999,0,255.
You can also, if necessary, select one of the following resampling methods to use:
- Nearest neighbor is the most appropriate resampling method to use with discrete data. It identifies the gray level of the pixel closest to the specified input coordinates and assigns that value to the output coordinates. Although this method is considered the most efficient in computation time, it introduces small errors in the output image. The output image may be offset spatially by up to half a pixel, which may cause the image to have a jagged appearance.
- Bilinear interpolation determines the gray level from the weighted average of the nine closest pixels to the specified input coordinates and assigns that value to the output coordinates. This method generates an image with a smoother appearance than nearest neighbor, but the gray-level values are altered in the process, which can result in blurring or loss of image resolution. Similar to cubic-convolution resampling, bilinear interpolation is most appropriate for continuous data.
- Cubic convolution determines the gray level from the weighted average of the 16 pixels closest to the specified input coordinates and assigns that value to the output coordinates. The resulting image is slightly sharper than one produced with bilinear interpolation, and it does not have the disjointed appearance produced by nearest neighbor. Similar to bilinear interpolation, cubic convolution is most appropriate for continuous data.
The default method is
Cubic convolution.
To specify NoData values and select a resampling method
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In the Output NoData box, type the NoData value or values you want to use for the output mosaic, if necessary.
The value is zero by default.
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In the Resampling method list, select from the following the method you want.
- Nearest neighbor
- Bilinear interpolation
- Cubic convolution
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Proceed to Modifying the extents.