A tolerance of 0.5 will guarantee a shift occurs. The unit of tolerance is a pixel with a valid value range of 0 to 0.5. If the difference in pixel alignment (of the incoming dataset and the target dataset) is less than the tolerance, resampling will not occur and a shift will be performed. If the difference in pixel alignment (of the incoming dataset and the target dataset) is greater than the tolerance, resampling will occur. The mosaicking tolerance controls whether resampling of the pixels will occur or the pixels will be shifted. When there is a misalignment of pixels, you need to decide whether to resample or shift the data. When mosaicking occurs, the target and the source pixels do not always line up exactly. The target raster and input rasters must have the same number of bands. If the CRF dataset was created using the Create Raster Dataset tool, you can update the mosaic dataset with new data, and the extent will be adjusted automatically. The Mosaic tool supports expandable CRF data. When the target raster is a multidimensional CRF, only the matching slices at the same dimensions for the same variable will be updated. If the output extent does need to be adjusted, use the Clip tool to clip the Target Raster parameter value after processing. The Mosaic tool doesn't use the output extent environment setting because the tool tends to create very large raster datasets and the output extent setting may clip the data. Otherwise, Mosaic will automatically resample the raster datasets using nearest neighbor resampling, which is not appropriate for continuous data types. The Color Matching Method parameter allows you to choose an algorithm to color match the datasets in your mosaic.įor floating-point input raster datasets of different resolutions or when cells are not aligned, it is recommended that you resample all the data using bilinear interpolation or cubic convolution before running Mosaic. If an improper color map mode is chosen, the output may not turn out as you expect. You can use the Mosaic tool even if the raster datasets have different color maps however, you must choose the proper color map mode. When mosaicking with raster datasets containing color maps, it is important to note the differences across the color maps for each raster dataset you mosaic. Geodatabase rasters will work without this extra step. Whenever possible, use the Last option for the Mosaic Operator parameter to mosaic raster datasets to an existing raster dataset in a geodatabase it is the most effective way to mosaic.įor file-based rasters, Ignore Background Value must be set to the same value as NoData for the background value to be ignored. The Blend and Mean options are best suited for continuous data. The Target Raster parameter value is considered the first raster in the list of input rasters.įor mosaicking of discrete data, the First, Minimum, or Maximum option in Mosaic Operator will provide the most meaningful results. For example, you can keep the color map of the most recent raster dataset used in the mosaic. There are also several options for handling a color map, if the raster dataset uses one. The overlapping areas of the mosaic can be handled in several ways for example, you can set the tool to keep only the first raster dataset's data, or you can blend the overlapping cell values. The multidimensional information from the first input multidimensional raster will be used to define the multidimensional information of the expandable raster dataset. If the target raster is a CRF format raster, the extent will be updated.Ī multidimensional raster dataset can be created by adding one or more multidimensional rasters to an empty expandable CRF raster dataset. Some mosaic techniques can help minimize the abrupt changes along the boundaries of the overlapping rasters. Mosaic is useful when two or more adjacent raster datasets need to be merged into one entity. The target raster must be an existing raster dataset, which can be an empty raster dataset or one that contains data.
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