Combining rasters at different resolutions

DanJensen1

I have a question regarding use of the combine tool.

I have two rasters, one at 3x3 resolution and one at 1x1 resolution.

When these rasters are combined using the "Combine" tool in the spatial analyst tool box (not considering arcpy), what method is used to determine the value in the new combined 3x3 raster?  There are no options for choosing an interpolation method for this tool.

There is no mention of this in directly in the tool information.  Does this tool work by choosing the value of the pixel closest to the centroid of the larger pixel or is there an average taken from all pixels intersecting the larger pixel.

Any insight would be appreciated.
Dan

curtvprice

When these rasters are combined using the "Combine" tool in the spatial analyst tool box (not considering arcpy), what method is used to determine the value in the new combined 3x3 raster? '

This is a really old question, but it popped up and deserves an answer in the thread.

Depending on the environment settings, the processing will happen at the cell size you specify in the environment. Resampling on the fly like this is done using nearest-neighbor interpolation.

Here are some examples based on the cellSize environment setting:

• Maximum of inputs = 3m
• Minimum of inputs = 1m
• Default = 3m (documented in tool help)
• any specified cell size.

If you want to do any other kind of sampling, this is done before the Combine using other tools (for example Resample or Aggregate).