So this is a pretty basic raster processing question, and perhaps it shouldn't be in the "technical" section of GeoNet, but not sure where else to post it so here goes:
I have a geotiff that that has all of its "background" values available as part of the regular attribute table (they're not "null"). The geotiff is from CropScape (it's a cropland data layer). Via the symbology, I can have the background values not display, but I'd like a more permanent version of having those become the "null" values that they're supposed to be.
When I run it through SetNull it does what I want (convert background values to null values). BUT, it also loses the connection to the colormap (which came with CropScape) that had conveniently been automatically symbolizing the non-background values in the original version.
1) Is there a way to reconnect the colormap to the new version to re-map based on the values? (I just don't want to have to manually enter the 50 different categories of landcover or lead students through a raster join...) I've tried exporting the colormap from the original one and then importing it to the new one, but isn't working.
2) Or, is there a way to run SetNull so that it operates on the value that you'd specified in the conditional statement (in this case, background) but doesn't otherwise lose the colormap link?
Thanks,
Diana